Zeitschriften und Ausgaben

Volumen 84 (2022): Heft 1 (October 2022)

Volumen 83 (2022): Heft 1 (August 2022)

Volumen 82 (2022): Heft 1 (April 2022)

Volumen 81 (2022): Heft 1 (January 2022)

Volumen 80 (2021): Heft 1 (October 2021)

Volumen 79 (2021): Heft 1 (July 2021)

Volumen 78 (2021): Heft 1 (March 2021)

Volumen 77 (2021): Heft 1 (January 2021)

Volumen 76 (2021): Heft 1 (January 2021)

Volumen 75 (2020): Heft 1 (October 2020)

Volumen 74 (2020): Heft 1 (August 2020)

Volumen 73 (2020): Heft 1 (July 2020)

Volumen 72 (2020): Heft 1 (March 2020)

Volumen 71 (2020): Heft 1 (January 2020)

Volumen 70 (2019): Heft 1 (November 2019)

Volumen 69 (2019): Heft 1 (October 2019)

Volumen 68 (2019): Heft 1 (August 2019)

Volumen 67 (2019): Heft 1 (June 2019)

Volumen 66 (2019): Heft 1 (March 2019)

Volumen 65 (2018): Heft 1 (December 2018)

Volumen 64 (2018): Heft 1 (September 2018)

Volumen 63 (2018): Heft 1 (August 2018)

Volumen 62 (2018): Heft 1 (June 2018)

Volumen 61 (2018): Heft 1 (March 2018)

Volumen 60 (2017): Heft 1 (December 2017)

Volumen 59 (2017): Heft 1 (October 2017)

Volumen 58 (2017): Heft 1 (September 2017)

Volumen 57 (2017): Heft 1 (June 2017)

Volumen 56 (2017): Heft 1 (February 2017)

Volumen 55 (2017): Heft 1 (January 2017)

Volumen 54 (2016): Heft 1 (December 2016)

Volumen 53 (2016): Heft 1 (December 2016)

Volumen 52 (2016): Heft 1 (September 2016)

Volumen 51 (2016): Heft 1 (June 2016)

Volumen 50 (2016): Heft 1 (April 2016)

Volumen 49 (2015): Heft 1 (December 2015)

Volumen 48 (2015): Heft 1 (December 2015)

Volumen 47 (2015): Heft 1 (September 2015)

Volumen 46 (2015): Heft 1 (June 2015)

Volumen 45 (2015): Heft 1 (March 2015)

Volumen 44 (2014): Heft 1 (December 2014)

Volumen 43 (2014): Heft 1 (November 2014)

Volumen 42 (2014): Heft 1 (September 2014)

Volumen 41 (2014): Heft 1 (June 2014)

Volumen 40 (2014): Heft 1 (March 2014)

Volumen 39 (2013): Heft 1 (December 2013)

Volumen 38 (2013): Heft 2013 (September 2013)

Volumen 37 (2013): Heft 1 (June 2013)

Volumen 36 (2013): Heft 1 (March 2013)

Volumen 35 (2012): Heft 1 (December 2012)

Volumen 34 (2012): Heft 1 (October 2012)

Volumen 33 (2012): Heft 2012 (June 2012)

Volumen 32 (2012): Heft 2012 (May 2012)
Aquatic Sports and Activities

Volumen 31 (2012): Heft 2012 (March 2012)

Volumen 30 (2011): Heft 2011 (December 2011)

Volumen 29A (2011): Heft Special-Heft (September 2011)
Presentation of the 1st International Symposium on Strength & Conditioning (ISSC 2011)

Volumen 29 (2011): Heft 2011 (September 2011)

Volumen 28 (2011): Heft 2011 (June 2011)

Volumen 27 (2011): Heft 2011 (March 2011)

Volumen 26 (2010): Heft 2010 (December 2010)

Volumen 25 (2010): Heft 2010 (September 2010)

Volumen 24 (2010): Heft 2010 (June 2010)

Volumen 23 (2010): Heft 2010 (March 2010)

Volumen 22 (2009): Heft 2009 (December 2009)

Volumen 21 (2009): Heft 2009 (June 2009)

Volumen 20 (2008): Heft 2008 (December 2008)

Volumen 19 (2008): Heft 2008 (June 2008)

Zeitschriftendaten
Format
Zeitschrift
eISSN
1899-7562
Erstveröffentlichung
13 Jan 2009
Erscheinungsweise
5 Hefte pro Jahr
Sprachen
Englisch

Suche

Volumen 81 (2022): Heft 1 (January 2022)

Zeitschriftendaten
Format
Zeitschrift
eISSN
1899-7562
Erstveröffentlichung
13 Jan 2009
Erscheinungsweise
5 Hefte pro Jahr
Sprachen
Englisch

Suche

25 Artikel

Section I - Kinesiology

Uneingeschränkter Zugang

Effects of Dual Task Interference on Biomechanics of the Entire Lower Extremity During the Drop Vertical Jump

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 5 - 14

Zusammenfassung

Abstract

The dual task is an important factor affecting knee biomechanics during jump-landing tasks. Athletes often have trouble in performing two tasks concurrently and a dual task can deteriorate landing performance. However, it is still unknown whether a dual task will affect the entire lower extremity. The purpose of this study was to clarify the effects of cognitive task interference on biomechanics of hip and ankle joints as well as the knee joint during the drop vertical jump (DVJ). A total of 20 female collegiate athletes participated in the study. Athletes performed a DVJ with or without a cognitive task. The DVJ was captured using a motion analysis system. Mental arithmetic of 2-digit addition was used as a cognitive task. Maximum vertical ground reaction force (vGRF), joint angles at initial contact (IC), joint moments within 40 milliseconds (ms) after IC, and joint angles and moments at peak vGRF were assessed. The data were statistically compared between with and without a cognitive task condition using a two-tailed paired t-test or the Wilcoxon singed rank test. The peak external knee abduction moment on both limbs within 40 ms after IC during the DVJ was significantly larger in the dual task than in the single task with less knee and hip flexion at initial contact. In addition, all moments of hip and ankle joints within 40 ms after IC were significantly larger in the dual task than in the single task accompanied with greater vGRF, except for the hip internal rotation moment. Cognitive tasks during a DVJ will result in biomechanical changes of the entire lower extremity in female athletes.

Key words

  • cognitive task
  • landing biomechanics
  • motion capture system
  • female athletes
Uneingeschränkter Zugang

The Flywheel Device Shaft Shape Determines Force and Velocity Profiles in the Half Squat Exercise

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 15 - 25

Zusammenfassung

Abstract

Flywheel resistance training devices can be classified by their shaft shape. The objective of this study was to analyze whether using two flywheel resistance training devices shaft shapes can influence force and velocity production, regardless of the inertia used. Thirty-nine (n = 39) healthy active men participated in this study. They were randomized to perform 3 sets of 7 repetitions at maximal concentric voluntary execution, followed by a break in the last third of the eccentric phase in the half squat exercise. A progressive rotational inertial setting of 0.11, 0.22, and 0.33 kg·m2 was used. Force- and velocity-time profiles were captured using two force plates and a synchronized linear encoder. Statistical parametric mapping was used to compare biomechanical output between the flywheel devices. The level of significance was set at p < 0.05. Force application was significantly higher in the horizontal cylinder-shaped device for the three moments of inertia used in the eccentric phase (p < 0.001). In the concentric phase, force application was significantly higher in the horizontal cylinder-shaped device in 0.11 (p < 0.001) and 0.22 kg·m2 (p < 0.001). The resultant speed was higher in the vertical cone-shaped device in the concentric phase and the eccentric phase for the three moments of inertia (p < 0.001). In conclusion, the flywheel shaft type determines the mechanical output of the half squat exercise, regardless of the moment of inertia used. While a horizontal cylinder-shaped device is more suitable to achieve higher forces, especially in the eccentric phase, a vertical cone-shaped device can be used to achieve higher speeds during the execution of the exercise.

Key words

  • muscle strength
  • exercise
  • eccentric overload
  • rotary inertia
  • monitoring
Uneingeschränkter Zugang

Agreement Between Kinovea Video Analysis and the Open Barbell System for Resistance Training Movement Outcomes

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 27 - 39

Zusammenfassung

Abstract

The purpose of this study was to examine the agreement between Kinovea video analysis software and the previously validated Open Barbell System (OBS) for assessing average concentric and eccentric velocity, eccentric duration, peak concentric velocity, height of peak concentric velocity, and concentric and eccentric range of motion. Sixteen resistance-trained males performed 11 repetitions at various intensities (between 60-100% of one-repetition maximum) on both the back squat and the bench press. For each repetition, all outcome measures were assessed with Kinovea and the OBS. Agreement between devices for each outcome measure was analyzed with paired t-tests, intraclass correlation coefficients with 95% confidence intervals, Bland-Altman plots, and folded empirical cumulative distribution plots (Mountain plots). All outcome variables were found to be statistically different (i.e. they did not agree) between the two devices (p < 0.001), except for average eccentric velocity (p = 0.315), as determined by the paired t-tests. Mountain plots had long tails for every outcome measure and Bland-Altman plots showed large limits of agreement for all outcome measures except concentric range of motion and the height of peak concentric velocity, demonstrating low agreement between devices. Based upon these findings and the previous validation of the OBS, these devices should not be used interchangeably.

Key words

  • resistance training
  • kinematics
  • autoregulation
  • strength
  • biomechanics
  • velocity
Uneingeschränkter Zugang

Impact of Centre-of-Mass Acceleration on Perceived Exertion, the Metabolic Equivalent and Heart Rate Reserve in Triathlete Spin Cycling: A Pilot Study

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 41 - 52

Zusammenfassung

Abstract

Indoor spin cycling has gained popularity as a training modality for triathletes. Part of its appeal is that it can form a component of a structured periodised training program and provide an alternative to outdoor cycling. Indices of physiological components (i.e., the metabolic equivalent, caloric cost, perceived exertion) and changes in the body position can be inferred by wearable technology such as an accelerometer. This pilot study aimed to investigate the relationship between the rating of perceived exertion, heart rate reserve, and the metabolic equivalent between the whole body centre of mass acceleration using a sacrum mounted triaxial accelerometer during 20 minutes of 6 varied power conditions of indoor spin cycling. Compared with other conditions, cycling at a steady state (>152-205 W) resulted in extremely large effects (> 0.9) in mediolateral acceleration and the rating of perceived exertion (p < 0.0001). The relationship between the body position (aerodynamic to drops) induced significant changes in anteroposterior acceleration magnitude (p < 0.0001), although moving from drops to the aerodynamic position was not significant despite a large increase in heart rate reserve and extremely large effects of perceived exertion. The rating of perceived exertion scale and the metabolic equivalent comparative to the whole body centre of mass acceleration magnitude and power displayed a strong correlation (r = 0.865). An individually determined whole body centre of mass accelerations combined with perceived exertion, the metabolic equivalent and heart rate reserve could potentially contribute to improved indoor triathlete spin cycling performance.

Key words

  • spin cycling
  • trunk centre of mass
  • accelerometer
  • fatigue
  • MET
  • triathlon

Section II - Exercise Physiology & Sports Medicine

Uneingeschränkter Zugang

The Effect of Inspiratory Muscle Training on the Pulmonary Function in Mixed Martial Arts and Kickboxing Athletes

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 53 - 63

Zusammenfassung

Abstract

Inspiratory muscle training (IMT) has found its way into athletes’ routine as a promising way of improving pulmonary function in combination with standard training. The objective of the study was to examine the effects of resistive IMT on the pulmonary function variables in athletes of two combat sports, i.e., mixed martial arts (MMA) and kickboxing. Fourteen kickboxing and 12 MMA male athletes qualified for the study. They were randomly assigned into experimental and control groups. While both groups participated in their standard training, the experimental group additionally participated in IMT which consisted of 30 breaths twice a day for 6 weeks. The pulmonary functions were measured at baseline and after 6 weeks of IMT. The addition of IMT to standard training increased significantly the forced expiratory volume in the first second to vital capacity ratio (FEV1/VC), and the maximum voluntary ventilation (MVV) (p < 0.05) with changes of 5.7%, and 28.6%, respectively, in MMA athletes. The kickboxing group showed no significant changes. The interaction of the sport discipline and IMT intervention yielded a strong significant change in the MVV (F(1, 11) = 14.53, p < 0.01), and FEV1/VC (F(1, 11) = 20.67, p < 0.01) to the benefit of MMA athletes in comparison with kickboxing athletes. Combining resistive IMT for 6 weeks with standard training was effective to improve some pulmonary functions in MMA athletes, but did not lead to additional gains in kickboxing athletes.

Key words

  • resistance inspiratory muscle trainer
  • combat sports
  • spirometry
  • respiratory function
  • lung volumes
Uneingeschränkter Zugang

Thigh Muscularity and Sprinting Performance of National‐Level Long‐Distance Runners

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 65 - 72

Zusammenfassung

Abstract

Long-distance runners require aerobic capacity as well as sprinting ability for superior performance; however, the factors which determine the sprinting ability of long-distance runners remain undetermined. Therefore, the purpose of our study was to examine the association between thigh muscle size and sprinting ability in national-level male long-distance runners. Nineteen male long-distance runners with 5000 m personal-best times of 13:12.63–14:14.87 participated in this study, and transaxial images of their right thighs were collected using magnetic resonance imaging. The cross-sectional areas of the quadriceps femoris, hamstrings, and adductor muscles were calculated from the transaxial images at 30%, 50%, and 70% of the distance from the greater trochanter to the lower edge of the femur; these areas were normalized by body mass. Sprint times for 100 m and 400 m were recorded on an all-weather track. The results revealed positive correlations between the normalized cross-sectional areas of the quadriceps femoris at 50% and 70% of the thigh length and the 100 m (r = 0.666, p = 0.002 and r = 0.531, p = 0.019, respectively) and 400 m sprint times (r = 0.769, p < 0.001 and r = 0.580, p = 0.009, respectively); hence, the larger the quadriceps, the slower the sprint speed. However, no association was found between the normalized cross-sectional areas of the hamstrings or adductor muscles and sprinting performance. Therefore, running motions which activate the quadriceps femoris much more than the hamstrings and adductor muscles should be avoided by national-level long-distance runners.

Key words

  • quadriceps femoris
  • hamstrings
  • adductor muscle
  • muscle cross-sectional area
  • long-distance running performance
Uneingeschränkter Zugang

Day‐to‐day Variation of the Heart Rate, Heart Rate Variability, and Energy Expenditure during FIFA 11+ and Dynamic Warm‐up Exercises

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 73 - 84

Zusammenfassung

Abstract

There seems to be a scarcity in literature investigating day-to-day warm-up (WU) variations. We investigated day-to-day variation of psychophysiological responses during Fédération Internationale de Football Association (FIFA) 11+ and dynamic warm-up (DWU) exercises. Twenty-one male collegiate soccer players were randomly assigned to the FIFA 11+ (n = 10) or DWU group (n = 11). Each group performed the assigned WU protocol on three different occasions with a 48-h interval in between. The inter-day variation of the heart rate (HR), time distribution of HR zones, heart rate variability (HRV), estimated energy expenditure (EE), blood lactate (BL) concentration, and the Borg rating of perceived exertion (RPE) were recorded. A two-way repeated measures of analysis of variance was used to compare the differences in chosen variables [group (2) × day (3)]. The coefficient of variation was used to determine the dispersion of the variables over the sessions. The interclass correlation coefficient (ICC) with a two-way random model and a single measure (ICC2,1) was used to determine inter-day reliability. There were no significant differences in time spent at particular HR zones and EE in both groups. The FIFA 11+ exercises showed high reliability of exercise duration, average HR (HRaverage), minimal HR (HRmin), peak HR (HRpeak), and post-exercise RPE. In the DWU group, high reliability was found only in HRaverage, HRpeak, and post-exercise RPE. The FIFA 11+ exercises showed similar EE, exercise HR patterns, BL, and RPE compared to the DWU. The FIFA 11+ program is an intense WU protocol with a characteristically low variation of day-to-day exercise HR and RPE responses.

Key words

  • performance
  • cardiovascular responses
  • soccer
  • warm-up exercise
  • repeated measurement
  • heart rate responses
Uneingeschränkter Zugang

Seasonal Training Load Monitoring Among Elite Level Soccer Players: Perceived Exertion and Creatine Kinase Variations Between Microcycles

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 85 - 95

Zusammenfassung

Abstract

The primary aim of the investigation was to determine the daily load variations between the microcycles of an entire season of an elite group of professional soccer players. The second aim of this study was to determine the relationships between Foster’s rating of perceived exertion (RPE), the Hooper index (HI) and CK levels over the weekly microcycles of the season. Thirty-five male professional soccer players participated in this study (3 goalkeepers, 6 wide defenders, 4 central defenders, 9 midfielders, 8 wide midfielders and 4 forwards) (25.7 ± 5.0 years, 182.3 ± 6.4 cm; 79.1 ± 7.0 kg). Significant differences between months in the variables of HI (p = 0.001; ES = 0.052), minT (p = 0.001; ES = 0.066), IL (p = 0.001; ES = 0.052, minimum effect) and CK (p = 0.002; ES = 0.031) were found. Comparison of the HI (p = 0.044; ES = 0.002), minT (p = 0.001; ES = 0.045), and IL (p = 0.001; ES = 0.045) revealed significant differences between microcycles. No significant differences were found in CK (p = 0.710; ES = 0.001) across the period. A significantly higher internal training load and fatigue perception in microcycles with only one official match was found. The greater load occurred 3 to 4 days before the game. In addition, it can be concluded that the first quarter of the season seemed to induce a greater physical demand on elite professional players.

Key words

  • training monitoring
  • blood sample
  • perceived scales
  • microcycle
Uneingeschränkter Zugang

Ultrasound Shear Modulus and Thickness of Lateral Abdominal Muscles in Different Contractile States in Relation to Self‐ Reported Hip/Groin Problems in Youth Soccer Players

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 97 - 108

Zusammenfassung

Abstract

To date, no studies have assessed lateral abdominal muscles’ (LAM) elasticity and thickness in relation to hip and groin symptoms in any population. The objectives were to a) assess the relationship between LAM ultrasound measurements (elasticity and thickness) and self-reported subscales of the Copenhagen Hip and Groin Outcome Score (HAGOS) and b) compare LAM elasticity and thickness between asymptomatic and symptomatic sides. Shear modulus and thickness of the oblique external (OE), internal (OI) and transversus abdominis (TrA) muscles in 25 young soccer players were assessed at rest and during isometric contraction using ultrasound shear wave elastography. HAGOS subscales were used to assess self-reported hip/groin problems. There was a significant (p < 0.05) moderate correlation between allometric-scaled OI resting thickness (mean of right and left) and the Activities of Daily Living (r = 0.40), Sport (r = 0.57) and Quality of Life (QOL) (r = 0.41) HAGOS subscales. Also, a moderate significant correlation was found between allometric-scaled TrA resting thickness and the QOL subscale (r = 0.47). Moderate correlations were found between resting OI shear modulus and the QOL (r = 0.44), between right TrA shear modulus during contraction and Symptoms (r = 0.57), and between the left TrA shear modulus during contraction and Physical Activity (r = 0.41) subscales. No differences were found between the symptomatic and asymptomatic side in thickness and elasticity measurements among soccer players with unilateral symptoms (p > 0.05). The relationships found between LAM and hip/groin problems in youth male soccer players indicate that muscles are thinner and more elastic (less stiff) in more symptomatic athletes.

Key words

  • trunk
  • hip
  • ultrasound imaging
  • balance/postural stability
  • elasticity
  • shear wave elastography
Uneingeschränkter Zugang

Post‐Exercise Cold‐ and Contrasting‐Water Immersion Effects on Heart Rate Variability Recovery in International Handball Female Players

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 109 - 122

Zusammenfassung

Abstract

This study aimed to investigate the effect of water immersion (WI) on cardiac parasympathetic reactivation during recovery from handball training sessions in elite female players during a two-week training camp. On the first three days of both weeks, players completed a crossover design with one of three 60-min delayed post-exercise WI protocols or passive rest (PAS). Recovery interventions consisted of a period of 6-min cold-WI (10°C; CWI6) and two contrasting periods cold- and hot-WI (36°C): one session included 3 min cold + 2 min hot + 3 min cold and the other session 5 × 2 min with cold at the very end. Short-term measures of heart rate variability (HRV) were collected before and after handball training sessions, and after WI. Derived parasympathetic HRV indices collected daily showed lower values post-training compared to pre-training values (p < 0.0001, large ES). Individual handball training sessions revealed similar clear depression of the vagal tone throughout the training camp. The comparison between each WI protocol and PAS revealed significant time × condition interaction particularly for CWI6. All parasympathetic indices revealed higher post-recovery values in CWI6 than PAS (p < 0.001 –p < 0.0001, with large ES ranging from 0.86 to 0.94). Surprisingly, 60-min delayed post-training WI revealed for most of parasympathetic HRV indices higher values than pre-training. This study highlighted that post-exercise parasympathetic disruption was exacerbated in response to handball training, and the 60-min delayed WI recovery interventions improved parasympathetic reactivity. Cardiac vagal tone can be highly improved with CWI6 compared to PAS. For the purpose of HRV modulations, CWI6 is recommended for short-term recovery.

Key words

  • autonomic nervous system
  • fatigue
  • recovery
  • vagal tone
Uneingeschränkter Zugang

A Systematic Review of Long‐Distance Triathlon Musculoskeletal Injuries

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 123 - 134

Zusammenfassung

Abstract

The distribution of injuries affecting long-distance triathletes is yet to be fully understood. A systematic review was performed of the clinical literature to determine the epidemiology of musculoskeletal injuries affecting long-distance triathletes. Searched databases in Feb 2020 were PubMed, Medline, EMBASE, EMCARE, and CINHAL databases. Published observational research articles related to the incidence or prevalence of musculoskeletal injuries in long-distance triathletes (competing at “Ironman” full distance or greater), written in the English language and not restricted by age or gender or date were eligible. Of the 975 studies identified on the initial search, six studies met the inclusion criteria for analysis. The mean age (SD) of the long-distance triathletes in these studies was 35.1 (2.7) and the range was 21-68 years. Overuse injuries were most frequent with the incidence range of 37-91%, and acute injury incidence range was 24-27%. The knee and spine were the most frequent location of injury. Running and cycling were the most frequently affected disciplines. Elite athletes had a lower incidence of overuse injury (37%). The highest acute injury incidence (27%) was recorded in non-elite athletes. The quality of the studies was relatively poor with only one study satisfying >50% of the quality assessment tool questions and only two studies were prospective, the rest were retrospective cross-sectional studies. Overall, there is a lack of literature reporting on musculoskeletal injuries in long-distance triathletes. Overuse injuries, particularly in the knee, are the most frequently reported, running and cycling are the most frequent disciplines associated. Long-distance triathletes may have a lower incidence of both overuse and acute injuries.

Key words

  • sports injury
  • ultra triathlon
  • endurance
  • ironman
  • running
  • cycling
  • swimming

Section III - Sports Training

Uneingeschränkter Zugang

Evaluation of the Isometric and Dynamic Rates of Force Development in Multi-Joint Muscle Actions

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 135 - 148

Zusammenfassung

Abstract

The rate of force development (RFD) in the isometric leg press (ILP), the countermovement jump (CMJ) and the squat jump (SJ) were examined in twenty-three (9 females) team sport athletes aged 21-24 years. Peak force (Fpeak), peak rate of force development (RFDpeak) and RFD at different time epochs (0-50, 50-100, 100-150, 150-200) were calculated from the force-time curve, as well as CMJ and SJ height and the center of mass displacement. RFDpeak, RFD at 0-50, 50-100 and 100-150 ms and Fpeak were similar between the CMJ and the SJ (p = 0.26 to 0.99). Furthermore, RFD0-50 ms was similar between the ILP, the CMJ, and the SJ (p = 0.99 to 0.57). Higher values were observed in the ILP compared with the CMJ and the SJ in RFD50-100 ms and RFD100-150 ms (p < 0.001) and these differences were maintained even when RFD was scaled to body mass. The higher RFD normalized to Fpeak was attained at the 50-100 ms time interval with no differences between the ILP, CMJ and SJ and between males and females. These results suggest that the ability to exert rapid force is similar between the CMJ and the SJ, irrespective of the type of muscle action. Furthermore, RFD normalized to Fpeak is a muscle-force independent index of explosive force production, facilitating comparisons between individuals with different levels of muscle strength. The similarities between the CMJ and the SJ in RFDpeak, Fpeak, and RFD at different time epochs may imply that these types of jumps could be used interchangeably to assess explosive lower limb performance.

Key words

  • isometric strength
  • peak force
  • power
  • force time curve
  • vertical jump
Uneingeschränkter Zugang

Variations in Internal and External Training Load Measures and Neuromuscular Performance of Professional Soccer Players During a Preseason Training Period

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 149 - 162

Zusammenfassung

Abstract

We described the internal and external training loads (TLs) experienced by soccer players over a 4-week preseason, examined their effects on vertical jump (VJ) performance, and investigated the relationships between different TL variables. Eighteen professional soccer players performed 17 training sessions and 1 friendly-match (FM) over the preseason. The internal TL was obtained using the session-rating of perceived exertion method. The external TL variables collected were total and high-intensity distances, body-load, and high-metabolic power distance via the GPS system. VJ performance was assessed 13 times throughout the study. Moreover, total quality recovery and delayed onset muscle soreness were assessed before every training session as a measure of recovery status. Players were divided, using a median split analysis, into two groups, according to their VJ performance (i.e., “lower” and “higher” VJ). External TL variables displayed similar variations across training sessions and were significantly interrelated (r ranging from 0.48 to 0.88). In periods where higher internal TLs were detected, impaired recovery status was noticed. Notably, the higher VJ group exhibited decreased jump performance at post-test and higher internal and external TLs across the entire preseason (compared to the lower VJ group). From our results it is suggested that professional soccer players with higher VJ performance are potentially more susceptible to concurrent training effects.

Key words

  • team-sports
  • football
  • tracking systems
  • muscle power
  • monitoring systems
Uneingeschränkter Zugang

Small-Sided Soccer Games with Larger Relative Areas Result in Higher Physical and Physiological Responses: A Systematic and Meta-Analytical Review

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 163 - 176

Zusammenfassung

Abstract

This study aimed to systematically review the influence of the relative area on athletes’ physical and physiological responses (outcomes) during small-sided games of soccer which were not matched to the relative area. It also presents a meta-analysis comparing standard small-sided games protocols with different relative areas. We searched the Web of Science and Scopus electronic databases for literature published up to March 2020 following all PRISMA guidelines for selecting articles for a qualitative and quantitative synthesis. As a result, eleven articles matched the inclusion criteria. For the quantitative synthesis, a pooled random-effects model was used to make pairwise comparisons between protocols with larger or smaller areas in each selected study. Prediction intervals were used to assess the heterogeneity. We found positive effects of larger relative areas per player on their total distance (d = 0.73; 95% CI = 0.12–1.34; p = 0.006; medium to large effect), distance covered at high speed (d = 0.93; 95% CI = 0.22–1.65; p = 0.001; large effect), and mean heart rate (d = 0.52; 95% CI = 0.17–0.88; p = 0.008; medium effect). In other words, larger relative areas were found to induce higher physical and physiological responses in players. Future studies should consider the relative area per player when comparing data for different small-sided games configurations to avoid confounding variables. Also, coaches can use relative area per player calculations to easily predict increases and decreases in expected training loads for different versions of SSGs during training.

Key words

  • small-sided games
  • relative area per player
  • physical response
  • physiological response
Uneingeschränkter Zugang

Interactive Three-Phase Structure for Table Tennis Performance Analysis: Application to Elite Men’s Singles Matches

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 177 - 188

Zusammenfassung

Abstract

The aim of the current study was twofold: (a) to construct an Interactive Three-Phase Structure for table tennis performance analysis and (b) to apply the proposed structure to the performance analysis of elite men’s singles matches. The current structure makes improvements over the former ones in the following aspects: more comprehensive performance variables consisting of bilateral actions covering the whole rally competing process, a better phase division method fitting to the real match situation and more focused analysis achieved by the designed critical phase. The analysis of 56 elite men’s singles matches (5507 rallies) was conducted using the proposed structure. The results demonstrated that performance variables of the rally competing process ceasing in Phase 2 (initial attack and counterattack phase) were decisive for the rally outcome of elite men’s singles matches. The proposed structure provides practitioners with a better model to enhance the effectiveness of table tennis performance analysis.

Key words

  • racket sport
  • notational study
  • analytical method
Uneingeschränkter Zugang

Effect of Inter-Repetition Rest vs. Traditional Resistance Training on the Upper Body Strength Rate of Force Development and Triceps Brachii Muscle Architecture

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 189 - 198

Zusammenfassung

Abstract

The purpose of the study was to examine the effect of seven-week inter-repetition rest vs. traditional resistance training on upper body maximum strength, the rate of force development and triceps brachii muscle architecture. Sixteen male participants were equally assigned into the inter-repetition rest and the traditional group. In both groups, training included the bench press exercise performed with 4 sets of 6 maximum repetitions, two training sessions per week. Twenty-second inter-repetition rest was employed for the inter-repetition rest group only. Measurements before and after the training period included maximum strength in the bench press, the isometric upper body rate of force development and peak force and triceps brachii muscle architecture. Maximum strength increased significantly in both groups (inter-repetition rest group: 21.5 ± 5.7% vs. traditional group: 13.5 ± 7.2%, p < 0.05), however, the maximum strength percentage increase was greater in the inter-repetition rest group compared to the traditional group (p = 0.027). Upper body isometric peak force increased only after inter-repetition rest training (10.7 ± 10.3%, p = 0.009). The rate of force development remained unchanged for both groups (p > 0.05), although percentage changes in time frames of 0-80 and 0-100 milliseconds were greater for the inter-repetition rest group compared to the traditional training group (p = 0.024 and p = 0.044, respectively). Triceps brachii thickness increased similarly for both groups (p < 0.05). These results suggest that inter-repetition rest may induce greater increases in maximum strength and the rate of force development compared to traditional training during the initial weeks of resistance training.

Key words

  • resistance training
  • upper body power
  • bench press
Uneingeschränkter Zugang

A Systematic Review of the Effects of Different Resistance Training Volumes on Muscle Hypertrophy

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 199 - 210

Zusammenfassung

Abstract

The main goal of this study was to compare responses to moderate and high training volumes aimed at inducing muscle hypertrophy. A literature search on 3 databases (Pubmed, Scopus and Chocrane Library) was conducted in January 2021. After analyzing 2083 resultant articles, studies were included if they met the following inclusion criteria: a) studies were randomized controlled trials (with the number of sets explicitly reported), b) interventions lasted at least six weeks, c) participants had a minimum of one year of resistance training experience, d) participants’ age ranged from 18 to 35 years, e) studies reported direct measurements of muscle thickness and/or the cross-sectional area, and f) studies were published in peer-review journals. Seven studies met the inclusion criteria and were included in the qualitative analysis, whereas just six were included in the quantitative analysis. All participants were divided into three groups: “low” (<12 weekly sets), “moderate” (12-20 weekly sets) and “high” volume (>20 weekly sets). According to the results of this meta-analysis, there were no differences between moderate and high training volume responses for the quadriceps (p = 0.19) and the biceps brachii (p = 0.59). However, it appears that a high training volume is better to induce muscle mass gains in the triceps brachii (p = 0.01). According to the results of this review, a range of 12-20 weekly sets per muscle group may be an optimum standard recommendation for increasing muscle hypertrophy in young, trained men.

Key words

  • strength
  • muscle mass
  • resistance training
  • muscle gains
  • training variables

Section IV - Sport of Disabled

Uneingeschränkter Zugang

Sports Injuries Among Players of the Polish National Team in Amputee Football in the Annual Training Cycle

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 211 - 219

Zusammenfassung

Abstract

The aim of the study was to determine the frequency, type and origin of the occurrence of injuries in amputee football. The studied group comprised all members of the Polish national amputee football team (n = 25). During the 9-month observation period, 13 players incurred 22 injuries. The incidence proportion was 48.0 per 100 athletes (95% Cl, 28.4-67.6) and the incidence rate was 5.73 per 1000 athlete-days (95% Cl, 3.33-8.12). The study showed that 32.8% of the injuries were to the thigh, 13.6% to the ankle, and 9.1% to the knee. The obtained results indicate that amputee football players rather frequently incur play-related injuries, but a single athlete incurs relatively few of them, with the lower limb being most commonly injured.

Key words

  • trauma
  • limbs amputations
  • team sports
  • adapted sports
  • physical disability
Uneingeschränkter Zugang

A Log-Linear Analysis of Efficiency in Wheelchair Basketball According to Player Classification

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 221 - 231

Zusammenfassung

Abstract

Within the framework of observational methodology, we conducted a log-linear analysis to study efficiency in relation to players’ functional ability in wheelchair basketball by analyzing associations between the position of the last pass before a shot, a shot position, and a shot result (favorable or unfavorable). The observation sample contained all offensive sequences ending in a shot by the US men’s wheelchair basketball team, who won the gold medal at the 2016 Paralympic Games in Rio de Janeiro. Data were annotated and coded in the Lince software program and their reliability confirmed by measuring interobserver agreement using Cohen’s kappa statistics. Log-linear modeling showed that the models generated to explain offensive sequences ending in a shot by players with greater functional ability were closest to models observed for professional basketball players and were the only models to show significant effects in terms of efficiency.

Key words

  • match analysis
  • US team
  • functional abilities
  • observational methodology
Uneingeschränkter Zugang

Are Teams whose Players are More Committed to the Team More Resilient? The Role of Intra-Group Conflict

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 233 - 242

Zusammenfassung

Abstract

The study aimed to analyze the relationship between commitment to the team and team resilience factors (characteristics of resilience and vulnerability under pressure), and to examine whether the task and social intra-group conflict act as mediators between commitment to the team and team resilience factors. One hundred seventy (170) male soccer players (16-38 years; M = 18.35; SD = 4.72) of the national teams of Argentina, Costa Rica, and Mexico participated in the study. The path analytic model was used to test mediating pathways. First, the results revealed that commitment to the team was positively related to characteristics of resilience and negatively to vulnerability under pressure. Second, bootstrap mediation analysis showed that athletes’ perceptions of the task and social intra-group conflict mediated the association between their perception of commitment to the team and team resilience factors. Findings provide initial evidence for a link between commitment to the team and team resilience in national teams and also suggest that intra-group conflict can improve the association between commitment to the team and team resilience. Therefore, the main conclusion of this study is that practioners should promote players’ commitment to the team and avoid intra-group conflicts within teams to have a resilient team that copes with problems more easily.

Key words

  • commitment to the team
  • intra-group conflict
  • group dynamics
  • team resilience
  • sport psychology
Uneingeschränkter Zugang

Mental Toughness Characteristics of Male University Athletes in Relation to Contextual Factors

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 243 - 251

Zusammenfassung

Abstract

Mental toughness is a psychological construct related to successful performance in academics, management, and sports among other sectors. However, studies on the determinants of mental toughness with respect to different human endeavours have remained inconclusive. This study explored mental toughness characteristics of male university athletes in selected sports in relation to contextual factors of athletes’ age, playing experience, year of study, and the type of sport. The Mental Toughness Questionnaire (MTQ48) was used to collect data from male university athletes (n = 140). Results of this study showed significant difference in the following components of MT: lower scores in challenge (p = .015), emotional control (p = .005), and life control (p = .002) among athletes with shorter playing experience, and higher scores in life control (p < .001), emotional control (p = .021), and confidence in abilities (p = .009) in handball as compared to soccer players. Soccer players had significantly higher scores in the challenge component (p = .038) of mental toughness as compared to handball players. It was concluded that playing experience and the type of sport influenced characteristics of mental toughness among university athletes. Coaches, trainers, and sports psychologists need to consider these contextual factors to optimize mental toughness of athletes. Future studies should explore how specific contextual factors influence training environments and outcomes, as well as how stakeholders can leverage on the relationships between playing experience, the type of sport and mental toughness to augment athletes’ mental toughness and sports performance.

Key words

  • challenge
  • commitment
  • confidence
  • emotional control
  • life control
Uneingeschränkter Zugang

Did the Absence of Crowd Support During the Covid-19 Pandemic Affect the Home Advantage in Brazilian Elite Soccer?

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 251 - 258

Zusammenfassung

Abstract

This study aimed to investigate the impact of crowd absence due to the COVID-19 pandemic on home advantage in Series A and B of professional Brazilian male soccer. Moreover, we sought to compare the home advantage between different competitive levels. Data from 2018 to 2020 Brazilian professional soccer championships (Series A and B) were analyzed, consisting of 2280 matches. The effect of home advantage was calculated in relation to the number of points won, the number of wins, goals scored and goals conceded. Our results indicated that home advantage was reduced in Serie A. Specifically, the 2020 (absence of the crowd) and 2019 seasons showed smaller home advantage compared to the 2018 season. On the other hand, Serie B analyses indicated no changes in home advantage over the seasons analyzed. The comparison of home advantage between competitive levels indicated higher home advantage in Serie A, exclusively in the 2018 season. In addition to the absence of fans, other changes occurred in elite sports due to the pandemic, such as changes in rules and the calendar. Considering that home advantage is affected by multiple interacting factors, it is important to investigate specific sports leagues across the world to determine which factors had the greatest impact on the advantage of playing home matches.

Key words

  • team performance
  • crowd support
  • match location
  • coronavirus
Uneingeschränkter Zugang

Interacting Constraints and Relative Age Effect in Elite Cross-Country Skiers and Freeskiers

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 259 - 268

Zusammenfassung

Abstract

Different characteristics of sports disciplines potentially lead to skewness in birth month distribution (relative age effect, RAE). These characteristics can be considered from a constraint-based approach with interacting environmental, task, and individual constraints as a theoretical framework with which to examine variations in RAE. The main aim of the present study was to examine the theoretical predictions of the constraint-based framework by investigating the birth month distribution in cross-country skiers and freeskiers at elite junior and senior levels. The sample was comprised of top ranked Norwegian U15–U19/20 cross-country skiers and junior-level freeskiers. Birth months of top ranked international senior-level skiers in cross-country and freeskiing were also collected. Results indicated an over-representation of skiers born in the first half versus the second half of the year at all junior ages in cross-country skiing. There was no significant difference in the distribution of birth months in freeskiing or in senior cross-country skiers or freeskiers. Based upon the interacting constraint framework, the skewness towards more early-born athletes in junior cross-country skiing could be due to strict age-grouped and results-oriented developmental programs beginning at an early age (environmental constraints) as well as high-demand for physical capabilities (task constraints) that favour more physically mature athletes (individual constraints). For freeskiing, the interacting environmental (less structured and more individualistic-oriented development), task (high technical/motor skill demands), and individual (no advantage of advanced physical maturation) constraints potentially operate in the opposite direction compared to cross-country skiing.

Key words

  • RAE
  • developmental variability
  • performance
  • contextual specificity
Uneingeschränkter Zugang

Validity of Performance Assessment Methods in Elite Paracanoeists

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 269 - 276

Zusammenfassung

Abstract

The problem of valid and reliable research methods in paralympic sports seems of great significance, thus the aim of this study was to evaluate the validity of the Wingate test (WAnT) in assessment of anaerobic performance in elite paracanoeists competing in 200 m races. Seven paralympic athletes (32.6 ± 7.76 years), medal winners and finalists of the Paralympic Games, World and European Championships, as well as World Cups were examined. The evaluations were conducted during a competition which was held at the paralympic distance of 200 m, and included the WAnT for upper limbs and the anaerobic threshold test (ATT). Correlations of selected indices of mechanical work and power in the WAnT, as well as anaerobic threshold (AT) power, with the time recorded during the competition were used to determine indices which affected paracanoeing performance. The results indicated strong negative correlations with time achieved in the competition between peak power and total work in the WAnT, and AT power (R = -0.796 p = 0.032; R = -0.882 p = 0.009; R = -0.900 p < 0.001, respectively). The research confirmed the validity of the WAnT for the upper limbs to assess the performance level of paracanoeists. It may be concluded that the WAnT and ATT may be used for monitoring performance during the paralympic 200 m race.

Key words

  • paracanoe 200 m race
  • testing
  • anaerobic performance
  • prediction
Uneingeschränkter Zugang

The Impact of Internal Compensatory Mechanisms on Musculoskeletal Pain in Elite Polish Sitting Volleyball Players – A Preliminary Study

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 277 - 288

Zusammenfassung

Abstract

The purpose of the study was to evaluate the impact of (1) maximal muscular strength of the upper body and (2) fat mass on musculoskeletal pain and sagittal spinal curvature deviations in elite Polish sitting volleyball players. The study examined twelve players (age = 35.4 ± 6.9 years). The assessments were performed based on objective (anthropometric examinations, Medi Mouse, 1RM test) and subjective (NMQ = 7) measurements. All statistical analyses were performed using the SPSS. The lower back, the upper back and the neck were the most frequent painful areas. Statistical analyses showed a significant relationship between lumbar lordosis (LL) sagittal standing extension (r = 0.62; p = 0.03) and thoracic kyphosis (TK) sagittal standing flexion (r = -0.63; p = 0.28) with the 1RM. Furthermore, correlations between a body adiposity index and TK sagittal standing flexion and extension (r = -0.65; p = 0.05, r = - 0.58; p = 0.0.05) as well as LL sagittal standing flexion (r = 0.61; p = 0.05) were found. The body mass index correlated with wrist pain, whereas a very high relationship was found between pain in the wrists and knee joints. Neck pain positively correlated with TK and LL sagittal standing. Low back pain correlated with LL sagittal standing flexion and TK sagittal standing extension. Fat mass impacts the depth of anteroposterior spinal curvatures, what may cause pain in the neck and the lower back. The 1 RM bench press may influence the prevalence and location of musculoskeletal pain, whereas its values might be predicted by the depth of TK. A lower 1RM in the bench press may impact sagittal spinal curvature deviations. Deepen TK and LL significantly contribute to the prevalence of the neck pain.

Key words

  • BAI
  • 1RM
  • bench press
  • spinal curvature
  • NMQ
  • Medi Mouse
25 Artikel

Section I - Kinesiology

Uneingeschränkter Zugang

Effects of Dual Task Interference on Biomechanics of the Entire Lower Extremity During the Drop Vertical Jump

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 5 - 14

Zusammenfassung

Abstract

The dual task is an important factor affecting knee biomechanics during jump-landing tasks. Athletes often have trouble in performing two tasks concurrently and a dual task can deteriorate landing performance. However, it is still unknown whether a dual task will affect the entire lower extremity. The purpose of this study was to clarify the effects of cognitive task interference on biomechanics of hip and ankle joints as well as the knee joint during the drop vertical jump (DVJ). A total of 20 female collegiate athletes participated in the study. Athletes performed a DVJ with or without a cognitive task. The DVJ was captured using a motion analysis system. Mental arithmetic of 2-digit addition was used as a cognitive task. Maximum vertical ground reaction force (vGRF), joint angles at initial contact (IC), joint moments within 40 milliseconds (ms) after IC, and joint angles and moments at peak vGRF were assessed. The data were statistically compared between with and without a cognitive task condition using a two-tailed paired t-test or the Wilcoxon singed rank test. The peak external knee abduction moment on both limbs within 40 ms after IC during the DVJ was significantly larger in the dual task than in the single task with less knee and hip flexion at initial contact. In addition, all moments of hip and ankle joints within 40 ms after IC were significantly larger in the dual task than in the single task accompanied with greater vGRF, except for the hip internal rotation moment. Cognitive tasks during a DVJ will result in biomechanical changes of the entire lower extremity in female athletes.

Key words

  • cognitive task
  • landing biomechanics
  • motion capture system
  • female athletes
Uneingeschränkter Zugang

The Flywheel Device Shaft Shape Determines Force and Velocity Profiles in the Half Squat Exercise

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 15 - 25

Zusammenfassung

Abstract

Flywheel resistance training devices can be classified by their shaft shape. The objective of this study was to analyze whether using two flywheel resistance training devices shaft shapes can influence force and velocity production, regardless of the inertia used. Thirty-nine (n = 39) healthy active men participated in this study. They were randomized to perform 3 sets of 7 repetitions at maximal concentric voluntary execution, followed by a break in the last third of the eccentric phase in the half squat exercise. A progressive rotational inertial setting of 0.11, 0.22, and 0.33 kg·m2 was used. Force- and velocity-time profiles were captured using two force plates and a synchronized linear encoder. Statistical parametric mapping was used to compare biomechanical output between the flywheel devices. The level of significance was set at p < 0.05. Force application was significantly higher in the horizontal cylinder-shaped device for the three moments of inertia used in the eccentric phase (p < 0.001). In the concentric phase, force application was significantly higher in the horizontal cylinder-shaped device in 0.11 (p < 0.001) and 0.22 kg·m2 (p < 0.001). The resultant speed was higher in the vertical cone-shaped device in the concentric phase and the eccentric phase for the three moments of inertia (p < 0.001). In conclusion, the flywheel shaft type determines the mechanical output of the half squat exercise, regardless of the moment of inertia used. While a horizontal cylinder-shaped device is more suitable to achieve higher forces, especially in the eccentric phase, a vertical cone-shaped device can be used to achieve higher speeds during the execution of the exercise.

Key words

  • muscle strength
  • exercise
  • eccentric overload
  • rotary inertia
  • monitoring
Uneingeschränkter Zugang

Agreement Between Kinovea Video Analysis and the Open Barbell System for Resistance Training Movement Outcomes

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 27 - 39

Zusammenfassung

Abstract

The purpose of this study was to examine the agreement between Kinovea video analysis software and the previously validated Open Barbell System (OBS) for assessing average concentric and eccentric velocity, eccentric duration, peak concentric velocity, height of peak concentric velocity, and concentric and eccentric range of motion. Sixteen resistance-trained males performed 11 repetitions at various intensities (between 60-100% of one-repetition maximum) on both the back squat and the bench press. For each repetition, all outcome measures were assessed with Kinovea and the OBS. Agreement between devices for each outcome measure was analyzed with paired t-tests, intraclass correlation coefficients with 95% confidence intervals, Bland-Altman plots, and folded empirical cumulative distribution plots (Mountain plots). All outcome variables were found to be statistically different (i.e. they did not agree) between the two devices (p < 0.001), except for average eccentric velocity (p = 0.315), as determined by the paired t-tests. Mountain plots had long tails for every outcome measure and Bland-Altman plots showed large limits of agreement for all outcome measures except concentric range of motion and the height of peak concentric velocity, demonstrating low agreement between devices. Based upon these findings and the previous validation of the OBS, these devices should not be used interchangeably.

Key words

  • resistance training
  • kinematics
  • autoregulation
  • strength
  • biomechanics
  • velocity
Uneingeschränkter Zugang

Impact of Centre-of-Mass Acceleration on Perceived Exertion, the Metabolic Equivalent and Heart Rate Reserve in Triathlete Spin Cycling: A Pilot Study

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 41 - 52

Zusammenfassung

Abstract

Indoor spin cycling has gained popularity as a training modality for triathletes. Part of its appeal is that it can form a component of a structured periodised training program and provide an alternative to outdoor cycling. Indices of physiological components (i.e., the metabolic equivalent, caloric cost, perceived exertion) and changes in the body position can be inferred by wearable technology such as an accelerometer. This pilot study aimed to investigate the relationship between the rating of perceived exertion, heart rate reserve, and the metabolic equivalent between the whole body centre of mass acceleration using a sacrum mounted triaxial accelerometer during 20 minutes of 6 varied power conditions of indoor spin cycling. Compared with other conditions, cycling at a steady state (>152-205 W) resulted in extremely large effects (> 0.9) in mediolateral acceleration and the rating of perceived exertion (p < 0.0001). The relationship between the body position (aerodynamic to drops) induced significant changes in anteroposterior acceleration magnitude (p < 0.0001), although moving from drops to the aerodynamic position was not significant despite a large increase in heart rate reserve and extremely large effects of perceived exertion. The rating of perceived exertion scale and the metabolic equivalent comparative to the whole body centre of mass acceleration magnitude and power displayed a strong correlation (r = 0.865). An individually determined whole body centre of mass accelerations combined with perceived exertion, the metabolic equivalent and heart rate reserve could potentially contribute to improved indoor triathlete spin cycling performance.

Key words

  • spin cycling
  • trunk centre of mass
  • accelerometer
  • fatigue
  • MET
  • triathlon

Section II - Exercise Physiology & Sports Medicine

Uneingeschränkter Zugang

The Effect of Inspiratory Muscle Training on the Pulmonary Function in Mixed Martial Arts and Kickboxing Athletes

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 53 - 63

Zusammenfassung

Abstract

Inspiratory muscle training (IMT) has found its way into athletes’ routine as a promising way of improving pulmonary function in combination with standard training. The objective of the study was to examine the effects of resistive IMT on the pulmonary function variables in athletes of two combat sports, i.e., mixed martial arts (MMA) and kickboxing. Fourteen kickboxing and 12 MMA male athletes qualified for the study. They were randomly assigned into experimental and control groups. While both groups participated in their standard training, the experimental group additionally participated in IMT which consisted of 30 breaths twice a day for 6 weeks. The pulmonary functions were measured at baseline and after 6 weeks of IMT. The addition of IMT to standard training increased significantly the forced expiratory volume in the first second to vital capacity ratio (FEV1/VC), and the maximum voluntary ventilation (MVV) (p < 0.05) with changes of 5.7%, and 28.6%, respectively, in MMA athletes. The kickboxing group showed no significant changes. The interaction of the sport discipline and IMT intervention yielded a strong significant change in the MVV (F(1, 11) = 14.53, p < 0.01), and FEV1/VC (F(1, 11) = 20.67, p < 0.01) to the benefit of MMA athletes in comparison with kickboxing athletes. Combining resistive IMT for 6 weeks with standard training was effective to improve some pulmonary functions in MMA athletes, but did not lead to additional gains in kickboxing athletes.

Key words

  • resistance inspiratory muscle trainer
  • combat sports
  • spirometry
  • respiratory function
  • lung volumes
Uneingeschränkter Zugang

Thigh Muscularity and Sprinting Performance of National‐Level Long‐Distance Runners

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 65 - 72

Zusammenfassung

Abstract

Long-distance runners require aerobic capacity as well as sprinting ability for superior performance; however, the factors which determine the sprinting ability of long-distance runners remain undetermined. Therefore, the purpose of our study was to examine the association between thigh muscle size and sprinting ability in national-level male long-distance runners. Nineteen male long-distance runners with 5000 m personal-best times of 13:12.63–14:14.87 participated in this study, and transaxial images of their right thighs were collected using magnetic resonance imaging. The cross-sectional areas of the quadriceps femoris, hamstrings, and adductor muscles were calculated from the transaxial images at 30%, 50%, and 70% of the distance from the greater trochanter to the lower edge of the femur; these areas were normalized by body mass. Sprint times for 100 m and 400 m were recorded on an all-weather track. The results revealed positive correlations between the normalized cross-sectional areas of the quadriceps femoris at 50% and 70% of the thigh length and the 100 m (r = 0.666, p = 0.002 and r = 0.531, p = 0.019, respectively) and 400 m sprint times (r = 0.769, p < 0.001 and r = 0.580, p = 0.009, respectively); hence, the larger the quadriceps, the slower the sprint speed. However, no association was found between the normalized cross-sectional areas of the hamstrings or adductor muscles and sprinting performance. Therefore, running motions which activate the quadriceps femoris much more than the hamstrings and adductor muscles should be avoided by national-level long-distance runners.

Key words

  • quadriceps femoris
  • hamstrings
  • adductor muscle
  • muscle cross-sectional area
  • long-distance running performance
Uneingeschränkter Zugang

Day‐to‐day Variation of the Heart Rate, Heart Rate Variability, and Energy Expenditure during FIFA 11+ and Dynamic Warm‐up Exercises

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 73 - 84

Zusammenfassung

Abstract

There seems to be a scarcity in literature investigating day-to-day warm-up (WU) variations. We investigated day-to-day variation of psychophysiological responses during Fédération Internationale de Football Association (FIFA) 11+ and dynamic warm-up (DWU) exercises. Twenty-one male collegiate soccer players were randomly assigned to the FIFA 11+ (n = 10) or DWU group (n = 11). Each group performed the assigned WU protocol on three different occasions with a 48-h interval in between. The inter-day variation of the heart rate (HR), time distribution of HR zones, heart rate variability (HRV), estimated energy expenditure (EE), blood lactate (BL) concentration, and the Borg rating of perceived exertion (RPE) were recorded. A two-way repeated measures of analysis of variance was used to compare the differences in chosen variables [group (2) × day (3)]. The coefficient of variation was used to determine the dispersion of the variables over the sessions. The interclass correlation coefficient (ICC) with a two-way random model and a single measure (ICC2,1) was used to determine inter-day reliability. There were no significant differences in time spent at particular HR zones and EE in both groups. The FIFA 11+ exercises showed high reliability of exercise duration, average HR (HRaverage), minimal HR (HRmin), peak HR (HRpeak), and post-exercise RPE. In the DWU group, high reliability was found only in HRaverage, HRpeak, and post-exercise RPE. The FIFA 11+ exercises showed similar EE, exercise HR patterns, BL, and RPE compared to the DWU. The FIFA 11+ program is an intense WU protocol with a characteristically low variation of day-to-day exercise HR and RPE responses.

Key words

  • performance
  • cardiovascular responses
  • soccer
  • warm-up exercise
  • repeated measurement
  • heart rate responses
Uneingeschränkter Zugang

Seasonal Training Load Monitoring Among Elite Level Soccer Players: Perceived Exertion and Creatine Kinase Variations Between Microcycles

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 85 - 95

Zusammenfassung

Abstract

The primary aim of the investigation was to determine the daily load variations between the microcycles of an entire season of an elite group of professional soccer players. The second aim of this study was to determine the relationships between Foster’s rating of perceived exertion (RPE), the Hooper index (HI) and CK levels over the weekly microcycles of the season. Thirty-five male professional soccer players participated in this study (3 goalkeepers, 6 wide defenders, 4 central defenders, 9 midfielders, 8 wide midfielders and 4 forwards) (25.7 ± 5.0 years, 182.3 ± 6.4 cm; 79.1 ± 7.0 kg). Significant differences between months in the variables of HI (p = 0.001; ES = 0.052), minT (p = 0.001; ES = 0.066), IL (p = 0.001; ES = 0.052, minimum effect) and CK (p = 0.002; ES = 0.031) were found. Comparison of the HI (p = 0.044; ES = 0.002), minT (p = 0.001; ES = 0.045), and IL (p = 0.001; ES = 0.045) revealed significant differences between microcycles. No significant differences were found in CK (p = 0.710; ES = 0.001) across the period. A significantly higher internal training load and fatigue perception in microcycles with only one official match was found. The greater load occurred 3 to 4 days before the game. In addition, it can be concluded that the first quarter of the season seemed to induce a greater physical demand on elite professional players.

Key words

  • training monitoring
  • blood sample
  • perceived scales
  • microcycle
Uneingeschränkter Zugang

Ultrasound Shear Modulus and Thickness of Lateral Abdominal Muscles in Different Contractile States in Relation to Self‐ Reported Hip/Groin Problems in Youth Soccer Players

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 97 - 108

Zusammenfassung

Abstract

To date, no studies have assessed lateral abdominal muscles’ (LAM) elasticity and thickness in relation to hip and groin symptoms in any population. The objectives were to a) assess the relationship between LAM ultrasound measurements (elasticity and thickness) and self-reported subscales of the Copenhagen Hip and Groin Outcome Score (HAGOS) and b) compare LAM elasticity and thickness between asymptomatic and symptomatic sides. Shear modulus and thickness of the oblique external (OE), internal (OI) and transversus abdominis (TrA) muscles in 25 young soccer players were assessed at rest and during isometric contraction using ultrasound shear wave elastography. HAGOS subscales were used to assess self-reported hip/groin problems. There was a significant (p < 0.05) moderate correlation between allometric-scaled OI resting thickness (mean of right and left) and the Activities of Daily Living (r = 0.40), Sport (r = 0.57) and Quality of Life (QOL) (r = 0.41) HAGOS subscales. Also, a moderate significant correlation was found between allometric-scaled TrA resting thickness and the QOL subscale (r = 0.47). Moderate correlations were found between resting OI shear modulus and the QOL (r = 0.44), between right TrA shear modulus during contraction and Symptoms (r = 0.57), and between the left TrA shear modulus during contraction and Physical Activity (r = 0.41) subscales. No differences were found between the symptomatic and asymptomatic side in thickness and elasticity measurements among soccer players with unilateral symptoms (p > 0.05). The relationships found between LAM and hip/groin problems in youth male soccer players indicate that muscles are thinner and more elastic (less stiff) in more symptomatic athletes.

Key words

  • trunk
  • hip
  • ultrasound imaging
  • balance/postural stability
  • elasticity
  • shear wave elastography
Uneingeschränkter Zugang

Post‐Exercise Cold‐ and Contrasting‐Water Immersion Effects on Heart Rate Variability Recovery in International Handball Female Players

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 109 - 122

Zusammenfassung

Abstract

This study aimed to investigate the effect of water immersion (WI) on cardiac parasympathetic reactivation during recovery from handball training sessions in elite female players during a two-week training camp. On the first three days of both weeks, players completed a crossover design with one of three 60-min delayed post-exercise WI protocols or passive rest (PAS). Recovery interventions consisted of a period of 6-min cold-WI (10°C; CWI6) and two contrasting periods cold- and hot-WI (36°C): one session included 3 min cold + 2 min hot + 3 min cold and the other session 5 × 2 min with cold at the very end. Short-term measures of heart rate variability (HRV) were collected before and after handball training sessions, and after WI. Derived parasympathetic HRV indices collected daily showed lower values post-training compared to pre-training values (p < 0.0001, large ES). Individual handball training sessions revealed similar clear depression of the vagal tone throughout the training camp. The comparison between each WI protocol and PAS revealed significant time × condition interaction particularly for CWI6. All parasympathetic indices revealed higher post-recovery values in CWI6 than PAS (p < 0.001 –p < 0.0001, with large ES ranging from 0.86 to 0.94). Surprisingly, 60-min delayed post-training WI revealed for most of parasympathetic HRV indices higher values than pre-training. This study highlighted that post-exercise parasympathetic disruption was exacerbated in response to handball training, and the 60-min delayed WI recovery interventions improved parasympathetic reactivity. Cardiac vagal tone can be highly improved with CWI6 compared to PAS. For the purpose of HRV modulations, CWI6 is recommended for short-term recovery.

Key words

  • autonomic nervous system
  • fatigue
  • recovery
  • vagal tone
Uneingeschränkter Zugang

A Systematic Review of Long‐Distance Triathlon Musculoskeletal Injuries

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 123 - 134

Zusammenfassung

Abstract

The distribution of injuries affecting long-distance triathletes is yet to be fully understood. A systematic review was performed of the clinical literature to determine the epidemiology of musculoskeletal injuries affecting long-distance triathletes. Searched databases in Feb 2020 were PubMed, Medline, EMBASE, EMCARE, and CINHAL databases. Published observational research articles related to the incidence or prevalence of musculoskeletal injuries in long-distance triathletes (competing at “Ironman” full distance or greater), written in the English language and not restricted by age or gender or date were eligible. Of the 975 studies identified on the initial search, six studies met the inclusion criteria for analysis. The mean age (SD) of the long-distance triathletes in these studies was 35.1 (2.7) and the range was 21-68 years. Overuse injuries were most frequent with the incidence range of 37-91%, and acute injury incidence range was 24-27%. The knee and spine were the most frequent location of injury. Running and cycling were the most frequently affected disciplines. Elite athletes had a lower incidence of overuse injury (37%). The highest acute injury incidence (27%) was recorded in non-elite athletes. The quality of the studies was relatively poor with only one study satisfying >50% of the quality assessment tool questions and only two studies were prospective, the rest were retrospective cross-sectional studies. Overall, there is a lack of literature reporting on musculoskeletal injuries in long-distance triathletes. Overuse injuries, particularly in the knee, are the most frequently reported, running and cycling are the most frequent disciplines associated. Long-distance triathletes may have a lower incidence of both overuse and acute injuries.

Key words

  • sports injury
  • ultra triathlon
  • endurance
  • ironman
  • running
  • cycling
  • swimming

Section III - Sports Training

Uneingeschränkter Zugang

Evaluation of the Isometric and Dynamic Rates of Force Development in Multi-Joint Muscle Actions

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 135 - 148

Zusammenfassung

Abstract

The rate of force development (RFD) in the isometric leg press (ILP), the countermovement jump (CMJ) and the squat jump (SJ) were examined in twenty-three (9 females) team sport athletes aged 21-24 years. Peak force (Fpeak), peak rate of force development (RFDpeak) and RFD at different time epochs (0-50, 50-100, 100-150, 150-200) were calculated from the force-time curve, as well as CMJ and SJ height and the center of mass displacement. RFDpeak, RFD at 0-50, 50-100 and 100-150 ms and Fpeak were similar between the CMJ and the SJ (p = 0.26 to 0.99). Furthermore, RFD0-50 ms was similar between the ILP, the CMJ, and the SJ (p = 0.99 to 0.57). Higher values were observed in the ILP compared with the CMJ and the SJ in RFD50-100 ms and RFD100-150 ms (p < 0.001) and these differences were maintained even when RFD was scaled to body mass. The higher RFD normalized to Fpeak was attained at the 50-100 ms time interval with no differences between the ILP, CMJ and SJ and between males and females. These results suggest that the ability to exert rapid force is similar between the CMJ and the SJ, irrespective of the type of muscle action. Furthermore, RFD normalized to Fpeak is a muscle-force independent index of explosive force production, facilitating comparisons between individuals with different levels of muscle strength. The similarities between the CMJ and the SJ in RFDpeak, Fpeak, and RFD at different time epochs may imply that these types of jumps could be used interchangeably to assess explosive lower limb performance.

Key words

  • isometric strength
  • peak force
  • power
  • force time curve
  • vertical jump
Uneingeschränkter Zugang

Variations in Internal and External Training Load Measures and Neuromuscular Performance of Professional Soccer Players During a Preseason Training Period

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 149 - 162

Zusammenfassung

Abstract

We described the internal and external training loads (TLs) experienced by soccer players over a 4-week preseason, examined their effects on vertical jump (VJ) performance, and investigated the relationships between different TL variables. Eighteen professional soccer players performed 17 training sessions and 1 friendly-match (FM) over the preseason. The internal TL was obtained using the session-rating of perceived exertion method. The external TL variables collected were total and high-intensity distances, body-load, and high-metabolic power distance via the GPS system. VJ performance was assessed 13 times throughout the study. Moreover, total quality recovery and delayed onset muscle soreness were assessed before every training session as a measure of recovery status. Players were divided, using a median split analysis, into two groups, according to their VJ performance (i.e., “lower” and “higher” VJ). External TL variables displayed similar variations across training sessions and were significantly interrelated (r ranging from 0.48 to 0.88). In periods where higher internal TLs were detected, impaired recovery status was noticed. Notably, the higher VJ group exhibited decreased jump performance at post-test and higher internal and external TLs across the entire preseason (compared to the lower VJ group). From our results it is suggested that professional soccer players with higher VJ performance are potentially more susceptible to concurrent training effects.

Key words

  • team-sports
  • football
  • tracking systems
  • muscle power
  • monitoring systems
Uneingeschränkter Zugang

Small-Sided Soccer Games with Larger Relative Areas Result in Higher Physical and Physiological Responses: A Systematic and Meta-Analytical Review

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 163 - 176

Zusammenfassung

Abstract

This study aimed to systematically review the influence of the relative area on athletes’ physical and physiological responses (outcomes) during small-sided games of soccer which were not matched to the relative area. It also presents a meta-analysis comparing standard small-sided games protocols with different relative areas. We searched the Web of Science and Scopus electronic databases for literature published up to March 2020 following all PRISMA guidelines for selecting articles for a qualitative and quantitative synthesis. As a result, eleven articles matched the inclusion criteria. For the quantitative synthesis, a pooled random-effects model was used to make pairwise comparisons between protocols with larger or smaller areas in each selected study. Prediction intervals were used to assess the heterogeneity. We found positive effects of larger relative areas per player on their total distance (d = 0.73; 95% CI = 0.12–1.34; p = 0.006; medium to large effect), distance covered at high speed (d = 0.93; 95% CI = 0.22–1.65; p = 0.001; large effect), and mean heart rate (d = 0.52; 95% CI = 0.17–0.88; p = 0.008; medium effect). In other words, larger relative areas were found to induce higher physical and physiological responses in players. Future studies should consider the relative area per player when comparing data for different small-sided games configurations to avoid confounding variables. Also, coaches can use relative area per player calculations to easily predict increases and decreases in expected training loads for different versions of SSGs during training.

Key words

  • small-sided games
  • relative area per player
  • physical response
  • physiological response
Uneingeschränkter Zugang

Interactive Three-Phase Structure for Table Tennis Performance Analysis: Application to Elite Men’s Singles Matches

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 177 - 188

Zusammenfassung

Abstract

The aim of the current study was twofold: (a) to construct an Interactive Three-Phase Structure for table tennis performance analysis and (b) to apply the proposed structure to the performance analysis of elite men’s singles matches. The current structure makes improvements over the former ones in the following aspects: more comprehensive performance variables consisting of bilateral actions covering the whole rally competing process, a better phase division method fitting to the real match situation and more focused analysis achieved by the designed critical phase. The analysis of 56 elite men’s singles matches (5507 rallies) was conducted using the proposed structure. The results demonstrated that performance variables of the rally competing process ceasing in Phase 2 (initial attack and counterattack phase) were decisive for the rally outcome of elite men’s singles matches. The proposed structure provides practitioners with a better model to enhance the effectiveness of table tennis performance analysis.

Key words

  • racket sport
  • notational study
  • analytical method
Uneingeschränkter Zugang

Effect of Inter-Repetition Rest vs. Traditional Resistance Training on the Upper Body Strength Rate of Force Development and Triceps Brachii Muscle Architecture

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 189 - 198

Zusammenfassung

Abstract

The purpose of the study was to examine the effect of seven-week inter-repetition rest vs. traditional resistance training on upper body maximum strength, the rate of force development and triceps brachii muscle architecture. Sixteen male participants were equally assigned into the inter-repetition rest and the traditional group. In both groups, training included the bench press exercise performed with 4 sets of 6 maximum repetitions, two training sessions per week. Twenty-second inter-repetition rest was employed for the inter-repetition rest group only. Measurements before and after the training period included maximum strength in the bench press, the isometric upper body rate of force development and peak force and triceps brachii muscle architecture. Maximum strength increased significantly in both groups (inter-repetition rest group: 21.5 ± 5.7% vs. traditional group: 13.5 ± 7.2%, p < 0.05), however, the maximum strength percentage increase was greater in the inter-repetition rest group compared to the traditional group (p = 0.027). Upper body isometric peak force increased only after inter-repetition rest training (10.7 ± 10.3%, p = 0.009). The rate of force development remained unchanged for both groups (p > 0.05), although percentage changes in time frames of 0-80 and 0-100 milliseconds were greater for the inter-repetition rest group compared to the traditional training group (p = 0.024 and p = 0.044, respectively). Triceps brachii thickness increased similarly for both groups (p < 0.05). These results suggest that inter-repetition rest may induce greater increases in maximum strength and the rate of force development compared to traditional training during the initial weeks of resistance training.

Key words

  • resistance training
  • upper body power
  • bench press
Uneingeschränkter Zugang

A Systematic Review of the Effects of Different Resistance Training Volumes on Muscle Hypertrophy

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 199 - 210

Zusammenfassung

Abstract

The main goal of this study was to compare responses to moderate and high training volumes aimed at inducing muscle hypertrophy. A literature search on 3 databases (Pubmed, Scopus and Chocrane Library) was conducted in January 2021. After analyzing 2083 resultant articles, studies were included if they met the following inclusion criteria: a) studies were randomized controlled trials (with the number of sets explicitly reported), b) interventions lasted at least six weeks, c) participants had a minimum of one year of resistance training experience, d) participants’ age ranged from 18 to 35 years, e) studies reported direct measurements of muscle thickness and/or the cross-sectional area, and f) studies were published in peer-review journals. Seven studies met the inclusion criteria and were included in the qualitative analysis, whereas just six were included in the quantitative analysis. All participants were divided into three groups: “low” (<12 weekly sets), “moderate” (12-20 weekly sets) and “high” volume (>20 weekly sets). According to the results of this meta-analysis, there were no differences between moderate and high training volume responses for the quadriceps (p = 0.19) and the biceps brachii (p = 0.59). However, it appears that a high training volume is better to induce muscle mass gains in the triceps brachii (p = 0.01). According to the results of this review, a range of 12-20 weekly sets per muscle group may be an optimum standard recommendation for increasing muscle hypertrophy in young, trained men.

Key words

  • strength
  • muscle mass
  • resistance training
  • muscle gains
  • training variables

Section IV - Sport of Disabled

Uneingeschränkter Zugang

Sports Injuries Among Players of the Polish National Team in Amputee Football in the Annual Training Cycle

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 211 - 219

Zusammenfassung

Abstract

The aim of the study was to determine the frequency, type and origin of the occurrence of injuries in amputee football. The studied group comprised all members of the Polish national amputee football team (n = 25). During the 9-month observation period, 13 players incurred 22 injuries. The incidence proportion was 48.0 per 100 athletes (95% Cl, 28.4-67.6) and the incidence rate was 5.73 per 1000 athlete-days (95% Cl, 3.33-8.12). The study showed that 32.8% of the injuries were to the thigh, 13.6% to the ankle, and 9.1% to the knee. The obtained results indicate that amputee football players rather frequently incur play-related injuries, but a single athlete incurs relatively few of them, with the lower limb being most commonly injured.

Key words

  • trauma
  • limbs amputations
  • team sports
  • adapted sports
  • physical disability
Uneingeschränkter Zugang

A Log-Linear Analysis of Efficiency in Wheelchair Basketball According to Player Classification

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 221 - 231

Zusammenfassung

Abstract

Within the framework of observational methodology, we conducted a log-linear analysis to study efficiency in relation to players’ functional ability in wheelchair basketball by analyzing associations between the position of the last pass before a shot, a shot position, and a shot result (favorable or unfavorable). The observation sample contained all offensive sequences ending in a shot by the US men’s wheelchair basketball team, who won the gold medal at the 2016 Paralympic Games in Rio de Janeiro. Data were annotated and coded in the Lince software program and their reliability confirmed by measuring interobserver agreement using Cohen’s kappa statistics. Log-linear modeling showed that the models generated to explain offensive sequences ending in a shot by players with greater functional ability were closest to models observed for professional basketball players and were the only models to show significant effects in terms of efficiency.

Key words

  • match analysis
  • US team
  • functional abilities
  • observational methodology
Uneingeschränkter Zugang

Are Teams whose Players are More Committed to the Team More Resilient? The Role of Intra-Group Conflict

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 233 - 242

Zusammenfassung

Abstract

The study aimed to analyze the relationship between commitment to the team and team resilience factors (characteristics of resilience and vulnerability under pressure), and to examine whether the task and social intra-group conflict act as mediators between commitment to the team and team resilience factors. One hundred seventy (170) male soccer players (16-38 years; M = 18.35; SD = 4.72) of the national teams of Argentina, Costa Rica, and Mexico participated in the study. The path analytic model was used to test mediating pathways. First, the results revealed that commitment to the team was positively related to characteristics of resilience and negatively to vulnerability under pressure. Second, bootstrap mediation analysis showed that athletes’ perceptions of the task and social intra-group conflict mediated the association between their perception of commitment to the team and team resilience factors. Findings provide initial evidence for a link between commitment to the team and team resilience in national teams and also suggest that intra-group conflict can improve the association between commitment to the team and team resilience. Therefore, the main conclusion of this study is that practioners should promote players’ commitment to the team and avoid intra-group conflicts within teams to have a resilient team that copes with problems more easily.

Key words

  • commitment to the team
  • intra-group conflict
  • group dynamics
  • team resilience
  • sport psychology
Uneingeschränkter Zugang

Mental Toughness Characteristics of Male University Athletes in Relation to Contextual Factors

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 243 - 251

Zusammenfassung

Abstract

Mental toughness is a psychological construct related to successful performance in academics, management, and sports among other sectors. However, studies on the determinants of mental toughness with respect to different human endeavours have remained inconclusive. This study explored mental toughness characteristics of male university athletes in selected sports in relation to contextual factors of athletes’ age, playing experience, year of study, and the type of sport. The Mental Toughness Questionnaire (MTQ48) was used to collect data from male university athletes (n = 140). Results of this study showed significant difference in the following components of MT: lower scores in challenge (p = .015), emotional control (p = .005), and life control (p = .002) among athletes with shorter playing experience, and higher scores in life control (p < .001), emotional control (p = .021), and confidence in abilities (p = .009) in handball as compared to soccer players. Soccer players had significantly higher scores in the challenge component (p = .038) of mental toughness as compared to handball players. It was concluded that playing experience and the type of sport influenced characteristics of mental toughness among university athletes. Coaches, trainers, and sports psychologists need to consider these contextual factors to optimize mental toughness of athletes. Future studies should explore how specific contextual factors influence training environments and outcomes, as well as how stakeholders can leverage on the relationships between playing experience, the type of sport and mental toughness to augment athletes’ mental toughness and sports performance.

Key words

  • challenge
  • commitment
  • confidence
  • emotional control
  • life control
Uneingeschränkter Zugang

Did the Absence of Crowd Support During the Covid-19 Pandemic Affect the Home Advantage in Brazilian Elite Soccer?

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 251 - 258

Zusammenfassung

Abstract

This study aimed to investigate the impact of crowd absence due to the COVID-19 pandemic on home advantage in Series A and B of professional Brazilian male soccer. Moreover, we sought to compare the home advantage between different competitive levels. Data from 2018 to 2020 Brazilian professional soccer championships (Series A and B) were analyzed, consisting of 2280 matches. The effect of home advantage was calculated in relation to the number of points won, the number of wins, goals scored and goals conceded. Our results indicated that home advantage was reduced in Serie A. Specifically, the 2020 (absence of the crowd) and 2019 seasons showed smaller home advantage compared to the 2018 season. On the other hand, Serie B analyses indicated no changes in home advantage over the seasons analyzed. The comparison of home advantage between competitive levels indicated higher home advantage in Serie A, exclusively in the 2018 season. In addition to the absence of fans, other changes occurred in elite sports due to the pandemic, such as changes in rules and the calendar. Considering that home advantage is affected by multiple interacting factors, it is important to investigate specific sports leagues across the world to determine which factors had the greatest impact on the advantage of playing home matches.

Key words

  • team performance
  • crowd support
  • match location
  • coronavirus
Uneingeschränkter Zugang

Interacting Constraints and Relative Age Effect in Elite Cross-Country Skiers and Freeskiers

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 259 - 268

Zusammenfassung

Abstract

Different characteristics of sports disciplines potentially lead to skewness in birth month distribution (relative age effect, RAE). These characteristics can be considered from a constraint-based approach with interacting environmental, task, and individual constraints as a theoretical framework with which to examine variations in RAE. The main aim of the present study was to examine the theoretical predictions of the constraint-based framework by investigating the birth month distribution in cross-country skiers and freeskiers at elite junior and senior levels. The sample was comprised of top ranked Norwegian U15–U19/20 cross-country skiers and junior-level freeskiers. Birth months of top ranked international senior-level skiers in cross-country and freeskiing were also collected. Results indicated an over-representation of skiers born in the first half versus the second half of the year at all junior ages in cross-country skiing. There was no significant difference in the distribution of birth months in freeskiing or in senior cross-country skiers or freeskiers. Based upon the interacting constraint framework, the skewness towards more early-born athletes in junior cross-country skiing could be due to strict age-grouped and results-oriented developmental programs beginning at an early age (environmental constraints) as well as high-demand for physical capabilities (task constraints) that favour more physically mature athletes (individual constraints). For freeskiing, the interacting environmental (less structured and more individualistic-oriented development), task (high technical/motor skill demands), and individual (no advantage of advanced physical maturation) constraints potentially operate in the opposite direction compared to cross-country skiing.

Key words

  • RAE
  • developmental variability
  • performance
  • contextual specificity
Uneingeschränkter Zugang

Validity of Performance Assessment Methods in Elite Paracanoeists

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 269 - 276

Zusammenfassung

Abstract

The problem of valid and reliable research methods in paralympic sports seems of great significance, thus the aim of this study was to evaluate the validity of the Wingate test (WAnT) in assessment of anaerobic performance in elite paracanoeists competing in 200 m races. Seven paralympic athletes (32.6 ± 7.76 years), medal winners and finalists of the Paralympic Games, World and European Championships, as well as World Cups were examined. The evaluations were conducted during a competition which was held at the paralympic distance of 200 m, and included the WAnT for upper limbs and the anaerobic threshold test (ATT). Correlations of selected indices of mechanical work and power in the WAnT, as well as anaerobic threshold (AT) power, with the time recorded during the competition were used to determine indices which affected paracanoeing performance. The results indicated strong negative correlations with time achieved in the competition between peak power and total work in the WAnT, and AT power (R = -0.796 p = 0.032; R = -0.882 p = 0.009; R = -0.900 p < 0.001, respectively). The research confirmed the validity of the WAnT for the upper limbs to assess the performance level of paracanoeists. It may be concluded that the WAnT and ATT may be used for monitoring performance during the paralympic 200 m race.

Key words

  • paracanoe 200 m race
  • testing
  • anaerobic performance
  • prediction
Uneingeschränkter Zugang

The Impact of Internal Compensatory Mechanisms on Musculoskeletal Pain in Elite Polish Sitting Volleyball Players – A Preliminary Study

Online veröffentlicht: 10 Feb 2022
Seitenbereich: 277 - 288

Zusammenfassung

Abstract

The purpose of the study was to evaluate the impact of (1) maximal muscular strength of the upper body and (2) fat mass on musculoskeletal pain and sagittal spinal curvature deviations in elite Polish sitting volleyball players. The study examined twelve players (age = 35.4 ± 6.9 years). The assessments were performed based on objective (anthropometric examinations, Medi Mouse, 1RM test) and subjective (NMQ = 7) measurements. All statistical analyses were performed using the SPSS. The lower back, the upper back and the neck were the most frequent painful areas. Statistical analyses showed a significant relationship between lumbar lordosis (LL) sagittal standing extension (r = 0.62; p = 0.03) and thoracic kyphosis (TK) sagittal standing flexion (r = -0.63; p = 0.28) with the 1RM. Furthermore, correlations between a body adiposity index and TK sagittal standing flexion and extension (r = -0.65; p = 0.05, r = - 0.58; p = 0.0.05) as well as LL sagittal standing flexion (r = 0.61; p = 0.05) were found. The body mass index correlated with wrist pain, whereas a very high relationship was found between pain in the wrists and knee joints. Neck pain positively correlated with TK and LL sagittal standing. Low back pain correlated with LL sagittal standing flexion and TK sagittal standing extension. Fat mass impacts the depth of anteroposterior spinal curvatures, what may cause pain in the neck and the lower back. The 1 RM bench press may influence the prevalence and location of musculoskeletal pain, whereas its values might be predicted by the depth of TK. A lower 1RM in the bench press may impact sagittal spinal curvature deviations. Deepen TK and LL significantly contribute to the prevalence of the neck pain.

Key words

  • BAI
  • 1RM
  • bench press
  • spinal curvature
  • NMQ
  • Medi Mouse

Planen Sie Ihre Fernkonferenz mit Scienceendo