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Journal Details
Format
Journal
eISSN
1899-7562
First Published
13 Jan 2009
Publication timeframe
5 times per year
Languages
English

Search

Volume 54 (2016): Issue 1 (December 2016)

Journal Details
Format
Journal
eISSN
1899-7562
First Published
13 Jan 2009
Publication timeframe
5 times per year
Languages
English

Search

23 Articles

Section I – Kinesiology

Open Access

Performance Effects of Repetition Specific Gluteal Activation Protocols on Acceleration in Male Rugby Union Players

Published Online: 15 Dec 2016
Page range: 33 - 42

Abstract

Abstract

Warm-up protocols have the potential to cause an acute enhancement of dynamic sprinting performance. The purpose of this study was to evaluate the effects of three repetition specific gluteal activation warm-up protocols on acceleration performance in male rugby union players. Forty male academy rugby union players were randomly assigned to one of 4 groups (control, 5, 10 or 15 repetition gluteal activation group) and performed 10 m sprints at baseline and 30 s, 2, 4, 6 and 8 min after their specific intervention protocol. Five and ten meter sprint times were the dependent variable and dual-beam timing gates were used to record all sprint times. Repeated measures analysis of variance found no significant improvement in 5 and 10 m sprint times between baseline and post warm-up scores (p ≥ 0.05) for all groups. There were no reported significant differences between groups at any of the rest interval time points (p ≥ 0.05). However, when individual responses to the warm-up protocols were analyzed, the 15 repetition gluteal activation group had faster 10 m times post-intervention and this improvement was significant (p = 0.021). These results would indicate that there is no specific rest interval for any of the gluteal interventions that results in a potentiation effect on acceleration performance. However, the individual response analysis would seem to indicate that a 15 repetition gluteal activation warm-up protocol has a potentiating effect on acceleration performance provided that the rest interval is adequately and individually determined.

Keywords

  • plyometrics
  • rest interval
  • sprinting
  • warm-up
Open Access

Assessing Reactive Strength Measures in Jumping and Hopping Using the Optojump™ System

Published Online: 15 Dec 2016
Page range: 23 - 32

Abstract

Abstract

The aim of this study was to assess the concurrent validity of the Optojump™ system (Microgate, Bolzano, Italy) versus a force platform in the estimation of temporal and reactive strength measures. In two separate investigations, twenty physically active males performed double-leg and single-leg drop jumps from a box height of 0.3 m and a 10 s vertical bilateral hopping test. Contact time, flight time and total time (the sum of contact and flight time) were concurrently assessed during single and double-leg drop jumps and during hopping. Jump height, the reactive strength index and the reactive strength ratio were also calculated from contact time and flight time. Despite intraclass correlation coefficients (ICCs) for all variables being close to 1 (ICC > 0.975), a significant overestimation was found in contact time (0.005 ± 0.002 s) and underestimations in flight time (0.005 ± 0.003 s), the reactive strength index (0.04 ± 0.02 m·s-1) and the reactive strength ratio (0.07 ± 0.04). Overestimations in contact time and underestimations in flight time were attributed to the physical design of the Optojump™ system as the transmitter and receiver units were positioned 0.003 m above the floor level. The Optojump™ demonstrated excellent overall temporal validity with no differences found between systems for total time. Coaches are advised to be consistent with the instrumentation used to assess athletes, however, in the case of comparison between reactive strength values collected with the Optojump™ and values collected with a force platform, regression equations are provided.

Keywords

  • force platform
  • drop jump
  • jump height
  • contact time
  • validity, photoelectric cells
Open Access

Accuracy of a 10 Hz GPS Unit in Measuring Shuttle Velocity Performed at Different Speeds and Distances (5 – 20 M)

Published Online: 15 Dec 2016
Page range: 15 - 22

Abstract

Abstract

The aim of this study was to validate the accuracy of a 10 Hz GPS device (STATSports, Ireland) by comparing the instantaneous values of velocity determined with this device with those determined by kinematic (video) analysis (25 Hz). Ten male soccer players were required to perform shuttle runs (with 180° change of direction) at three velocities (slow: 2.2 m·s-1; moderate: 3.2 m·s-1; high: maximal) over four distances: 5, 10, 15 and 20 m. The experiments were video-recorded; the “point by point” values of speed recorded by the GPS device were manually downloaded and analysed in the same way as the “frame by frame” values of horizontal speed as obtained by video analysis. The obtained results indicated that shuttle distance was smaller in GPS than video analysis (p < 0.01). Shuttle velocity (shuttle distance/shuttle time) was thus smaller in GPS than in video analysis (p < 0.001); the percentage difference (bias, %) in shuttle velocity between methods was found to decrease with the distance covered (5 m: 9 ± 6%; 20 m: 3 ± 3%). The instantaneous values of speed were averaged; from these data and from data of shuttle time, the distance covered was recalculated; the error (criterion distance-recalculated distance) was negligible for video data (0.04 ± 0.28 m) whereas GPS data underestimated criterion distance (0.31 ± 0.55 m). In conclusion, the inaccuracy of this GPS unit in determining shuttle speed can be attributed to inaccuracy in determining the shuttle distance.

Keywords

  • GPS technology
  • team sports
  • time-motion analysis
  • performance analysis
  • shuttle runs
Open Access

Postural Preparation to Stepping: Coupled Center of Pressure Shifts in the Anterior-Posterior and Medio-Lateral Directions

Published Online: 15 Dec 2016
Page range: 5 - 14

Abstract

Abstract

We explored changes in the postural preparation to stepping introduced by modifications of the initial coordinates of the center of pressure (COP). We hypothesized that the postural adjustments in the anterior-posterior direction would persist across all initial COP manipulations while the adjustments in the medio-lateral direction would be highly sensitive to the initial COP coordinate. Healthy subjects stood on a force plate, shifted the body weight to one of the initial conditions that spanned the range of COP coordinates in both directions, and initiated a single step or started to walk. No major changes were observed between the stepping and walking conditions. Changes in the initial COP coordinate in the medio-lateral direction led to scaling of the magnitude of the COP shift in that direction prior to stepping accompanied by a nearly proportional change in the COP shift in the anterior-posterior direction. Changes in the initial COP coordinate in the anterior-posterior direction led to scaling of the magnitude of the COP shift in that direction prior to stepping without consistent changes in the COP shift in the medio-lateral direction. We interpret the results as reflecting a neural organization using a small set of referent body configurations for the postural adjustments.

Keywords

  • posture
  • stepping
  • center of pressure
  • biomechanics
  • referent configuration

Section II – Exercise Physiology & Sports Medicine

Open Access

Physiological Responses During the Time Limit at 100% of the Peak Velocity in the Carminatti’s Test in Futsal Players

Published Online: 15 Dec 2016
Page range: 91 - 101

Abstract

Abstract

The aim of this study was to investigate the physiological responses during the time limit at the intensity of the peak velocity of the Carminatti’s test (T-CAR). Ten professional futsal players (age, 27.4 ± 5.8 years, body mass, 78.8 ± 8.5 kg, body height, 175.8 ± 6.8 cm, body fat mass, 14.1 ± 2.6%) took part in the study. The players performed three tests, with an interval of at least 48 hours, as follows: the T-CAR to determine the peak velocity and the maximal heart rate; an incremental treadmill protocol to determine the maximal physiological responses; and a time limit running test at the peak velocity reached in the T-CAR. During the last two tests, a portable gas analyzer was used for direct measurement of cardiorespiratory variables. It was shown that the peak velocity was not significantly different from the maximal aerobic speed achieved in the laboratory (p = 0.213). All athletes reached their maximum oxygen uptake during the time limit test. The maximum oxygen uptake achieved during the time limit test was not different from that observed in the laboratory condition (51.1 ± 4.7 vs. 49.6 ± 4.7 ml·kg-1·min-1, respectively, p = 0.100). In addition, Bland and Altman plots evidenced acceptable agreement between them. On average, athletes took ~140 s to achieve maximum oxygen uptake and maintained it for ~180 s. Therefore, the peak velocity intensity can be used as an indicator of maximal aerobic power of futsal athletes and the time limit can be used as a reference for training prescription.

Keywords

  • intermittent field test
  • peak velocity
  • maximal aerobic power
  • time limit
Open Access

The Effect of Specific Sling Exercises on the Functional Movement Screen Score in Adolescent Volleyball Players: A Preliminary Study

Published Online: 15 Dec 2016
Page range: 83 - 90

Abstract

Abstract

The existing data indicate that the result of the Functional Movement Screen (FMS) test influences the likelihood of subsequent injury in professional athletes. Therefore, exercises increasing test scores of the FMS may be useful at various stages of sports activity. This study evaluated the effects of the NEURAC sling exercises method on the FMS test score in teenage volleyball players. The study was conducted on 15 volleyball players aged 14 years. The FMS test was performed three times interspersed with a two-month interval. Between the first and the second assessment, neither additional treatment nor training was applied, while between the second and the third assessment, the participants performed stabilisation exercises based on the NEURAC method. Training was carried out twice a week, for eight weeks. The analysis showed that between the first and the second measurement, no significant differences occurred. The use of specific sling exercises caused a significant improvement in FMS results (p ≤ 0.01) between the first and the third, as well as the second and the third measurement. The applied stabilisation exercises based on the NEURAC method positively influenced the FMS test result in male subjects practicing volleyball. Performance of such exercises also resulted in more than 90% of the subjects having a total FMS test score ≥ 17, which may be important in the prevention of injuries. The preliminary results indicate that this type of exercise should be included in a teenage volleyball training routine.

Keywords

  • stability exercise
  • Functional Movement Screen
  • injury
  • prevention
Open Access

Evaluation of the Effects of Neuromuscular Electrical Stimulation of The Lower Limbs Combined with Pulmonary Rehabilitation on Exercise Tolerance in Patients with Chronic Obstructive Pulmonary Disease

Published Online: 15 Dec 2016
Page range: 75 - 82

Abstract

Abstract

Chronic obstructive pulmonary disease (COPD) is a systemic disease with multiple extrapulmonary manifestations including impeded skeletal muscle function, leading to decreased muscular strength and endurance in patients with COPD. Pulmonary rehabilitation eases the symptoms of the condition and produces increased muscular endurance. Neuromuscular electrical stimulation (NMES) may serve as a treatment alternative to traditional pulmonary rehabilitation. The aim of the study was to assess the effects of NMES combined with pulmonary rehabilitation on exercise tolerance in patients in comparison with pulmonary rehabilitation alone. The subjects included 30 patients with COPD randomly assigned to one of the two groups. The first group consisted of 15 patients who were treated with neuromuscular electrical stimulation at frequency of 35Hz and pulmonary rehabilitation (NMES+RP). The second group comprised 15 patients treated with pulmonary rehabilitation only (RP). Pre- and poststudy assessments were performed. The retrospective evaluation including an exercise tolerance test (i.e. six minute walk test (6MWT)), spirometry and blood gasometry was carried out after 3 weeks. Twenty-eight patients in total completed the study. In the NMES+RP group, an increase in exercise tolerance manifested by a longer distance walked in the 6MWT was observed in comparison to the pulmonary rehabilitation group. No effects of NMES combined with pulmonary rehabilitation on selected spirometric and gasometric parameters in patients with COPD were observed in comparison with traditional pulmonary rehabilitation. The acquired results suggest that NMES of the lower limbs may be applied as an additional form of pulmonary rehabilitation in patients with COPD.

Keywords

  • COPD
  • neuromuscular electrical stimulation
  • exercise tolerance
Open Access

Somatic, Endurance Performance and Heart Rate Variability Profiles of Professional Soccer Players Grouped According to Age

Published Online: 15 Dec 2016
Page range: 65 - 74

Abstract

Abstract

This cross-sectional study compared somatic, endurance performance determinants and heart rate variability (HRV) profiles of professional soccer players divided into different age groups: GI (17–19.9 years; n = 23), GII (20–24.9 years; n = 45), GIII (25–29.9 years; n = 30), and GIV (30–39 years; n = 26). Players underwent somatic and HRV assessment and maximal exercise testing. HRV was analyzed by spectral analysis of HRV, and high (HF) and low (LF) frequency power was transformed by a natural logarithm (Ln). Players in GIV (83 ± 7 kg) were heavier (p < 0.05) compared to both GI (73 ± 6 kg), and GII (78 ± 6 kg). Significantly lower maximal oxygen uptake (VO2max, ml•kg-1•min-1) was observed for GIV (56.6 ± 3.8) compared to GI (59.6 ± 3.9), GII (59.4 ± 4.2) and GIV (59.7 ± 4.1). All agegroups, except for GII, demonstrated comparable relative maximal power output (Pmax). For supine HRV, significantly lower Ln HF (ms2) was identified in both GIII (7.1 ± 0.8) and GIV (6.9 ± 1.0) compared to GI (7.9 ± 0.6) and GII (7.7 ± 0.9). In conclusion, soccer players aged >25 years showed negligible differences in Pmax unlike the age group differences demonstrated in VO2max. A shift towards relative sympathetic dominance, particularly due to reduced vagal activity, was apparent after approximately 8 years of competing at the professional level.

Keywords

  • body composition
  • maximal oxygen uptake
  • vagal activity
  • sports career length, aging
Open Access

Leukocyte Populations are Associated with Heart Rate Variability After a Triathlon

Published Online: 15 Dec 2016
Page range: 55 - 63

Abstract

Abstract

The purpose of this study was to analyze cellular immune components and their association with heart rate variability in triathlon athletes. Twelve athletes were included (age 36.41 ± 5.57 years, body mass 81.84 ± 10.97 kg) and blood samples were taken one week before, immediately, at 2 and 48 hours, and one week after competition. Total lymphocytes and their subpopulations, neutrophils, basophils, eosinophils and monocytes were analyzed. At the same time, heart rate variability was recorded for 30 minutes using Polar Team2®. A significant difference between lymphocyte subpopulations and heart rate variability was found in the different study periods. A positive correlation was found between total lymphocytes and rMSSD (r = .736, p <0.05), CD3+ and rMSSD (r = .785, p <0.05), and CD4+ and rMSSD (r = .795, p < 0.05) at the end of the competition. After one week of competition, a negative correlation was found between eosinophils and MRR, SDNN, pNN50, and rMSSD (p <0.01); and basophils and MRR, SDNN, pNN50, and rMSSD (p <0.01); while a positive correlation was found between CD19+ (B cells) and pNN50 (r = .678, p <0.05). Our results suggest that it is possible to predict the effect of training with regard to the athlete's performance.

Keywords

  • exercise
  • lymphocytes
  • training
  • competition
Open Access

Does the MTHFR A1298C Polymorphism Modulate the Cardiorespiratory Response to Training?

Published Online: 15 Dec 2016
Page range: 43 - 53

Abstract

Abstract

The 5,10-methylenetetrahydrofolate reductase gene (MTHFR) A1298C polymorphic variant is a candidate to explain the individual differences in trainability and response to exercise training. Therefore, the aim of the study was to verify whether the A1298C polymorphism influenced the aerobic and anaerobic performance as well as body and mass composition in young Polish women following low-high impact aerobic exercise training. Two hundred and one women aged 21 ± 1 years (range 19–24) were included in the study. All of them completed a 12-week exercise training program and were measured for selected somatic features, aerobic capacity and cardiorespiratory fitness indices as well as peak anaerobic power and anaerobic capacity, before and after the intervention. A mixed 2 x 2 ANOVA for 20 dependent variables grouped in three categories was conducted. No significant interaction of the genotype with training for body mass and body composition variables was observed. Although, there were three significant genotype x training interactions for maximal oxygen uptake variables, regardless of body mass i.e.: for VO2max (p < 0.05), HRmax (p < 0.0001) and HRAT/HRmax (p < 0.0001). Significantly greater improvement in VO2max was gained by the CC+AC group compared to the AA genotype group. The present results support the hypothesis that individual differences in trainability are at least in part determined by the genetic component and MTHFR A1298C seems to be one of the many polymorphisms involved.

Keywords

  • MTHFR
  • gene polymorphism
  • exercise training

Section III – Sports Training

Open Access

Optimization of Game Formats in U-10 Soccer Using Logistic Regression Analysis

Published Online: 15 Dec 2016
Page range: 163 - 171

Abstract

Abstract

Small-sided games provide young soccer players with better opportunities to develop their skills and progress as individual and team players. There is, however, little evidence on the effectiveness of different game formats in different age groups, and furthermore, these formats can vary between and even within countries. The Royal Spanish Soccer Association replaced the traditional grassroots 7-a-side format (F-7) with the 8-a-side format (F-8) in the 2011-12 season and the country’s regional federations gradually followed suit. The aim of this observational methodology study was to investigate which of these formats best suited the learning needs of U-10 players transitioning from 5-aside futsal. We built a multiple logistic regression model to predict the success of offensive moves depending on the game format and the area of the pitch in which the move was initiated. Success was defined as a shot at the goal. We also built two simple logistic regression models to evaluate how the game format influenced the acquisition of technicaltactical skills. It was found that the probability of a shot at the goal was higher in F-7 than in F-8 for moves initiated in the Creation Sector-Own Half (0.08 vs 0.07) and the Creation Sector-Opponent's Half (0.18 vs 0.16). The probability was the same (0.04) in the Safety Sector. Children also had more opportunities to control the ball and pass or take a shot in the F-7 format (0.24 vs 0.20), and these were also more likely to be successful in this format (0.28 vs 0.19).

Keywords

  • soccer
  • adaptation
  • child
  • observational methodology
  • logistic regression
Open Access

Mechanical Differences between Barbell and Body Optimum Power Loads in the Jump Squat Exercise

Published Online: 15 Dec 2016
Page range: 153 - 162

Abstract

Abstract

This study compared the values of bar-peak force (PFBar) and power (PPBar), body-peak force (PFBody) and power (PPBody) and bar-mean propulsive power (MPPBar) in different jump-squat (JS) conditions: unloaded condition (UC); bar-loaded condition (BLC) and optimum bar-MPP condition (OBC). Twenty-five soccer players performed the JS using a bar with negligible mass (UC), using the Smith-machine bar (BLC) and using the load capable of maximizing the bar-MPP (OBC). The PFBody was significantly higher in the UC (2847.9 ± 489.1 N) than in the OBC (2655.4 ± 444.3 N). The UC presented greater PPBody (3775.9 ± 631.5 W) than the BLC (3359.7 ± 664.3 W) and OBC (3357.8 ± 625.3 W). The OBC presented higher values of PFBar, PPBar and MPPBar (676.2 ± 109.4 W) than the BLC (MPPBar = 425.8 ± 53.7 W) (all p < 0.05). In the OBC (compared to the UC), the body peak-power presented a reduction of ≈ 11%, while generating bar-power output from ≈ 59 to 73% higher than the BLC. While the fact that the body-peak power is maximized in the UC denotes a mechanical phenomenon, the bar-optimum load represents an intensity at which both components of the power equation (force and velocity) are optimized. This has important implications for sports training.

Keywords

  • optimal loads
  • muscle power
  • ballistic
  • plyometrics
  • neuromuscular
Open Access

Performance Assessment in Water Polo Using Compositional Data Analysis

Published Online: 15 Dec 2016
Page range: 143 - 151

Abstract

Abstract

The aim of the present study was to identify groups of offensive performance indicators which best discriminated between a match score (favourable, balanced or unfavourable) in water polo. The sample comprised 88 regular season games (2011-2014) from the Spanish Professional Water Polo League. The offensive performance indicators were clustered in five groups: Attacks in relation to the different playing situations; Shots in relation to the different playing situations; Attacks outcome; Origin of shots; Technical execution of shots. The variables of each group had a constant sum which equalled 100%. The data were compositional data, therefore the variables were changed by means of the additive log-ratio (alr) transformation. Multivariate discriminant analyses to compare the match scores were calculated using the transformed variables. With regard to the percentage of right classification, the results showed the group that discriminated the most between the match scores was “Attacks outcome” (60.4% for the original sample and 52.2% for cross-validation). The performance indicators that discriminated the most between the match scores in games with penalties were goals (structure coefficient (SC) = .761), counterattack shots (SC = .541) and counterattacks (SC = .481). In matches without penalties, goals were the primary discriminating factor (SC = .576). This approach provides a new tool to compare the importance of the offensive performance groups and their effect on the match score discrimination.

Keywords

  • performance profile
  • observational analysis
  • statistical data analysis
Open Access

Physical Performance During Water-Polo Matches: The Effect of the Players’ Competitive Level

Published Online: 15 Dec 2016
Page range: 135 - 142

Abstract

Abstract

The purpose of the study was to compare playing intensity and performance changes within a water-polo match in players of different competitive levels. High-level (n = 7) and lower-level (n = 7) players performed a progressively increasing speed test of 5 x 200 m swimming and speed corresponding to lactate concentration of 4.0, 5.0 and 10.0 mmol•l-1 was calculated. Repeated sprint ability (8 x 20 m) was tested at pre-, the middle and post-match and a 400 m swimming test was completed at pre and post in five water-polo matches. A t-test and a two-way ANOVA were used for statistical analysis. High-level compared to lower-level players presented higher speed corresponding to lactate concentration of 4.0 and 5.0 mmol•l-1 (p < 0.05). Regardless of the sports level, the mean heart rate was reduced towards the end of the match. High-level players completed a shorter amount of match time with the heart rate lower than 85% of the peak heart rate (p < 0.05). However, when the speed corresponding to lactate concentration of 4.0 mmol•l-1 was used as a covariate, no differences were observed in the heart rate between groups. Both groups decreased repeated sprint and 400 m performance at post- compared to pre-match by 7 ± 3% and 7 ± 4%, respectively. High-level compared to lower-level players showed better performance in repeated sprints at the middle (p < 0.01) and in pre-, post-match 400 m tests (p < 0.01). It was concluded that high-level compared to lower-level players completed the match at a higher playing intensity and presented a lower performance decrement across the match as a result of their higher aerobic endurance.

Keywords

  • team-sports
  • physical fitness
  • match-induced fatigue
Open Access

The Effects of Modifying the Distance of the Penalty Shot in Water Polo

Published Online: 15 Dec 2016
Page range: 127 - 133

Abstract

Abstract

The aim of this study was to determine the effects of changing the distance of the penalty shot in water polo from 4 to 5 m. While a shorter distance made the penalty shot more effective, it also reduced the use of this sanction. A total of 192 matches played in the 2003 and 2007 Water Polo World Championships were recorded. The sample included 278 penalty shots in both tournaments. Notational analysis using a longitudinal correlational and descriptive design was employed to determine whether a longer distance increased the number of sanctioned penalties (81 vs 197) and caused a non-significant decrease in scoring efficiency (7.4%) with significant differences in the relationship between the area and the type of a shot, with less centre and power shots (14.8% vs 7.1%) observed and predominance of bounce shots to the right of the goal posts. The rule change prompted more penalties, produced changes in shot direction as well as the type of a shot, and yielded a decrement of 7.4% in scoring efficiency.

Keywords

  • water polo
  • rules modification
  • penalty shot
Open Access

Evolution of Determinant Factors of Repeated Sprint Ability

Published Online: 15 Dec 2016
Page range: 115 - 126

Abstract

Abstract

The aim of this study was to investigate the changes in the relationships between repeated sprint ability (RSA) and anthropometric measures as well as fitness qualities in soccer players. Twenty-one professional soccer players performed several anthropometric and physical tests including countermovement vertical jumps (CMJs), a straight-line 30 m sprint (T30), an RSA test (6 x 20 + 20 m with 20 s recovery), a progressive isoinertial loading test in a full squat, a Yo-Yo Intermittent Recovery Test Level-1 (YYIRT-1) and a 20 m shuttle run test (20mSRT). The mean (RSAmean), the fastest (RSAbest), each single sprint time, and the percentage in a sprint decrease (%Dec) in the RSA test were calculated. RSAbest correlated significantly with RSAmean (r = .82) and with all single sprints (p < 0.05), showing a downward trend as the number of sprints performed increased. No significant relationship was observed between the %Dec and RSA performance. CMJs and the T30 also showed a correlation with RSA performance, whereas lower limb strength did not show any relationship with RSA performance. RSAmean showed significant (p < 0.05) relationships with body mass (r = .44), adiposity (r = .59) and the YYIRT-1 (r = -.62), increasing as the number of repeated sprints increased. The 20mSRT showed minimal relationships with RSA performance. In conclusion, maximal sprint capacity seems to be relevant for the RSA performance, mainly in the first sprints. However, high intermittent endurance capacity and low adiposity might help enhance the RSA performance when increasing the number of repeated sprints.

Keywords

  • anthropometrics
  • repeated explosive efforts
  • strength
  • sprinting
  • intermittent endurance
  • soccer
Open Access

Effects of Fatigue on Throwing Performance in Experienced Team Handball Players

Published Online: 15 Dec 2016
Page range: 103 - 113

Abstract

Abstract

The purpose of this study was to investigate the effect of central and peripheral physiological fatigue on throwing accuracy and ball release velocity in team handball. Twenty male subjects (age 24.7 ± 3.9 yrs, body mass 88.5 ± 5.0 kg, body height 1.86 ± 0.05 m, training experience 12.7 ± 3.8 yrs) from one handball team participated in this study. The participants completed four sets of eight laps of a circuit that consisted of specific team handball drills/exercises, with decreasing recovery times between the laps in each set in order to induce physiological fatigue. Duration of the recovery intervals determined the description of the effort made in each set: “light" (80 s recovery between laps), “moderate" (40 s), “hard" (20 s) and “very hard" (10 s). A heart rate, concentration of lactate in blood and the rate of perceived exertion (RPE) were recorded. Ball velocity and accuracy were measured after each set and they both decreased during a fatigue protocol. However, accuracy only decreased significantly in the end of the protocol, while ball release was already affected after the first round of the protocol. The results substantiate the initial hypothesis and confirm that both throwing accuracy and ball release velocity decrease significantly as physiological fatigue increases. These variables began to decrease when the fatigue quantification values were high or very high. The findings can be used by coaches to develop training programs to teach players how to identify fatigue thresholds and combat the effects of fatigue through decision-making skills at critical game moments.

Keywords

  • specific training
  • physiological fatigue
  • heart rate
  • blood lactate
  • rating of perceived exertion

Section IV – Behavioural Sciences in Sport

Open Access

Soccer Players Cultural Capital and Its Impact on Migration

Published Online: 15 Dec 2016
Page range: 195 - 206

Abstract

Abstract

The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player’s success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player’s previous attitudes and/or behaviours (habitus), significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu’s theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players’ cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach’s alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1) had 2.2 times and the second factor (F8) had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better “success conditions” in the talent development of young players.

Keywords

  • social cultural factors
  • soccer
  • talent development
Open Access

Quality Perception of the 2012 World Indoor Athletics Championships

Published Online: 15 Dec 2016
Page range: 181 - 194

Abstract

Abstract

The objective of this study was to compare the views of spectators concerning the quality perception of the World Indoor Athletics Championships. The study group consisted of 568 spectators who watched the events. A measurement scale of event quality in spectator sports (SEQSS) developed by Ko et al. (2011) was used as a data collection tool in the study. In order to determine the views of the spectators concerning the quality of the Indoor Athletics Championships, the dimensions constituting the scale were compared according to the demographic features of the sample group. As a consequence, important differences in most of the dimensions of the scale were revealed with respect to the demographic data of the subjects. The most relevant finding of the study is that the dimension of “physical environment quality”, which is one of the dimensions constituting the event quality, differed significantly in all comparisons that were made according to demographic features.

Keywords

  • event quality
  • spectator
  • service quality
Open Access

Developing Talented Soccer Players: An Analysis of Socio-Spatial Factors as Possible Key Constraints

Published Online: 15 Dec 2016
Page range: 227 - 236

Abstract

Abstract

Most studies on the identification and development of soccer talent have been one-dimensional in nature. Although some multi-dimensional analyses have been conducted, few research studies have assessed in any depth the socio-spatial factors influencing talent development. The aim of this particular study was to analyse variations in the international representation of clubs (n = 821) and countries (n = 59) in the development of players who took part in the 2014 FIFA Soccer World Cup. Clubs and countries were ranked and divided into quartiles according to the number of players developed between the ages of 15 and 21 (clubs and countries that developed players for at least three years between these ages) and the number of official league matches played by these players up to the age of 23. Significant variations were observed between clubs in terms of the number of developed players who took part in the World Cup and the number of official league matches played by these players up to the age of 23 (p < .05), and also between countries (p < .05). The findings reveal the need to carry out more in-depth studies into the type of training and competition engaged in by elite players in the period of development between the ages of 15 and 21. It may be the case that these factors are potentially decisive socio-spatial constraints in the development of soccer talent.

Keywords

  • social factors
  • talent development
  • training
  • ecological dynamics
Open Access

The Chronotype of Elite Athletes

Published Online: 15 Dec 2016
Page range: 219 - 225

Abstract

Abstract

The aims of this study were (i) to compare the chronotype distribution of elite athletes to a young adult population and (ii) to determine if there was a tendency for athletes to select and/or participate in sports which suited their chronotype. A total of 114 elite athletes from five sports (cricket, cycling, hockey, soccer and triathlon) participated in this study. The participants’ chronotype, sleepiness, sleep satisfaction and sleep quality were determined using the Horne and Östberg Morningness and Eveningness questionnaire, the Epworth Sleepiness Scale and questions concerning their sleep satisfaction and quality. All questionnaires were administered during a typical training phase that was not in the lead up to competition and/or post competition. No differences between chronotype group for sleepiness, sleep satisfaction or sleep quality were found. There was a significantly higher proportion of triathletes that were morning and intermediate types compared to the control group χ2 (2) = 7.5, p = 0.02. A significant relationship between sport and chronotype group (χ2(4)=15.9, p = 0.04) was observed, with a higher frequency of morning types involved in sports that required morning training. There was a clear indication that athletes tended to select and pursue sports that suited their chronotype. This was evident by the amount of morning types involved in morning sports. Given that athletes are more likely to pursue and excel in sports which suit their chronotype, it is recommended that coaches consider the athlete’s chronotype during selection processes or if possible design and implement changes to training schedules to either suit the athletes’ chronotype or the timing of an upcoming competition.

Keywords

  • sleep
  • circadian preference
  • sport
Open Access

A Comparison of Physical Education Students’ Motivation Using Polish and Turkish Versions of the Academic Motivation Scale

Published Online: 15 Dec 2016
Page range: 207 - 218

Abstract

Abstract

Motivation is an important phenomenon in the realm of education, particularly in the university fields connected with physical education and sport, where it is necessary to accommodate and balance intellectual abilities and physical fitness. The present study tested motivation levels among university students in the fields connected with physical education and sport in Poland and Turkey. It was based on the Self-Determination Theory (Deci and Ryan, 1985), namely intrinsic motivation, extrinsic motivation and amotivation which impact human behaviour. The Academic Motivation Scale was used (Vallerand et al., 1992). The aims of the study were twofold, first, to crossculturally validate Polish and Turkish versions of the Academic Motivation Scale and second, to identify and compare the motivation to study depending on nationality and gender. Both Polish and Turkish versions of the questionnaire were validated and converted to a four-factorial structure. The findings indicated that Polish and Turkish students’ motivation especially differed in amotivation and intrinsic motivation to know and experience stimulation. Moreover, Turkish female students proved to be at the lowest estimate of amotivation.

Keywords

  • intrinsic motivation
  • extrinsic motivation
  • physical education and sport

Section V – Book Review

Open Access

Periodization in Team Sport Games - A Review of Current Knowledge and Modern Trends in Competitive Sports

Published Online: 15 Dec 2016
Page range: 173 - 180

Abstract

Abstract

The main goal of this study was to present a review of current knowledge and modern trends in periodization of the training process in team sports. The research objectives were: an analysis of various aspects of periodization of the annual training cycle for elite athletes practicing team sport games, an attempt to determine both the examined and unexamined issues related with periodization of training as well as to indicate directions for further research, and finally, presentation of different training loads and competitions in micro-, meso- and macrocycles. The research consisted of the analysis and generalization of the bibliography, methods of monitoring training and competition loads of the Polish national U17 female soccer team in the seasons 2011/2012 and 2012/2013, as well as of the female basketball division one club in the season 2014/2015. Findings of the present study indicate resolved as well as unresolved aspects of annual training cycle periodization in team sport games and provide information on the types of training and competitive workload planning in micro-, meso- and macrocycles.

Keywords

  • team sport games
  • periodization
  • training loads
  • training cycles
23 Articles

Section I – Kinesiology

Open Access

Performance Effects of Repetition Specific Gluteal Activation Protocols on Acceleration in Male Rugby Union Players

Published Online: 15 Dec 2016
Page range: 33 - 42

Abstract

Abstract

Warm-up protocols have the potential to cause an acute enhancement of dynamic sprinting performance. The purpose of this study was to evaluate the effects of three repetition specific gluteal activation warm-up protocols on acceleration performance in male rugby union players. Forty male academy rugby union players were randomly assigned to one of 4 groups (control, 5, 10 or 15 repetition gluteal activation group) and performed 10 m sprints at baseline and 30 s, 2, 4, 6 and 8 min after their specific intervention protocol. Five and ten meter sprint times were the dependent variable and dual-beam timing gates were used to record all sprint times. Repeated measures analysis of variance found no significant improvement in 5 and 10 m sprint times between baseline and post warm-up scores (p ≥ 0.05) for all groups. There were no reported significant differences between groups at any of the rest interval time points (p ≥ 0.05). However, when individual responses to the warm-up protocols were analyzed, the 15 repetition gluteal activation group had faster 10 m times post-intervention and this improvement was significant (p = 0.021). These results would indicate that there is no specific rest interval for any of the gluteal interventions that results in a potentiation effect on acceleration performance. However, the individual response analysis would seem to indicate that a 15 repetition gluteal activation warm-up protocol has a potentiating effect on acceleration performance provided that the rest interval is adequately and individually determined.

Keywords

  • plyometrics
  • rest interval
  • sprinting
  • warm-up
Open Access

Assessing Reactive Strength Measures in Jumping and Hopping Using the Optojump™ System

Published Online: 15 Dec 2016
Page range: 23 - 32

Abstract

Abstract

The aim of this study was to assess the concurrent validity of the Optojump™ system (Microgate, Bolzano, Italy) versus a force platform in the estimation of temporal and reactive strength measures. In two separate investigations, twenty physically active males performed double-leg and single-leg drop jumps from a box height of 0.3 m and a 10 s vertical bilateral hopping test. Contact time, flight time and total time (the sum of contact and flight time) were concurrently assessed during single and double-leg drop jumps and during hopping. Jump height, the reactive strength index and the reactive strength ratio were also calculated from contact time and flight time. Despite intraclass correlation coefficients (ICCs) for all variables being close to 1 (ICC > 0.975), a significant overestimation was found in contact time (0.005 ± 0.002 s) and underestimations in flight time (0.005 ± 0.003 s), the reactive strength index (0.04 ± 0.02 m·s-1) and the reactive strength ratio (0.07 ± 0.04). Overestimations in contact time and underestimations in flight time were attributed to the physical design of the Optojump™ system as the transmitter and receiver units were positioned 0.003 m above the floor level. The Optojump™ demonstrated excellent overall temporal validity with no differences found between systems for total time. Coaches are advised to be consistent with the instrumentation used to assess athletes, however, in the case of comparison between reactive strength values collected with the Optojump™ and values collected with a force platform, regression equations are provided.

Keywords

  • force platform
  • drop jump
  • jump height
  • contact time
  • validity, photoelectric cells
Open Access

Accuracy of a 10 Hz GPS Unit in Measuring Shuttle Velocity Performed at Different Speeds and Distances (5 – 20 M)

Published Online: 15 Dec 2016
Page range: 15 - 22

Abstract

Abstract

The aim of this study was to validate the accuracy of a 10 Hz GPS device (STATSports, Ireland) by comparing the instantaneous values of velocity determined with this device with those determined by kinematic (video) analysis (25 Hz). Ten male soccer players were required to perform shuttle runs (with 180° change of direction) at three velocities (slow: 2.2 m·s-1; moderate: 3.2 m·s-1; high: maximal) over four distances: 5, 10, 15 and 20 m. The experiments were video-recorded; the “point by point” values of speed recorded by the GPS device were manually downloaded and analysed in the same way as the “frame by frame” values of horizontal speed as obtained by video analysis. The obtained results indicated that shuttle distance was smaller in GPS than video analysis (p < 0.01). Shuttle velocity (shuttle distance/shuttle time) was thus smaller in GPS than in video analysis (p < 0.001); the percentage difference (bias, %) in shuttle velocity between methods was found to decrease with the distance covered (5 m: 9 ± 6%; 20 m: 3 ± 3%). The instantaneous values of speed were averaged; from these data and from data of shuttle time, the distance covered was recalculated; the error (criterion distance-recalculated distance) was negligible for video data (0.04 ± 0.28 m) whereas GPS data underestimated criterion distance (0.31 ± 0.55 m). In conclusion, the inaccuracy of this GPS unit in determining shuttle speed can be attributed to inaccuracy in determining the shuttle distance.

Keywords

  • GPS technology
  • team sports
  • time-motion analysis
  • performance analysis
  • shuttle runs
Open Access

Postural Preparation to Stepping: Coupled Center of Pressure Shifts in the Anterior-Posterior and Medio-Lateral Directions

Published Online: 15 Dec 2016
Page range: 5 - 14

Abstract

Abstract

We explored changes in the postural preparation to stepping introduced by modifications of the initial coordinates of the center of pressure (COP). We hypothesized that the postural adjustments in the anterior-posterior direction would persist across all initial COP manipulations while the adjustments in the medio-lateral direction would be highly sensitive to the initial COP coordinate. Healthy subjects stood on a force plate, shifted the body weight to one of the initial conditions that spanned the range of COP coordinates in both directions, and initiated a single step or started to walk. No major changes were observed between the stepping and walking conditions. Changes in the initial COP coordinate in the medio-lateral direction led to scaling of the magnitude of the COP shift in that direction prior to stepping accompanied by a nearly proportional change in the COP shift in the anterior-posterior direction. Changes in the initial COP coordinate in the anterior-posterior direction led to scaling of the magnitude of the COP shift in that direction prior to stepping without consistent changes in the COP shift in the medio-lateral direction. We interpret the results as reflecting a neural organization using a small set of referent body configurations for the postural adjustments.

Keywords

  • posture
  • stepping
  • center of pressure
  • biomechanics
  • referent configuration

Section II – Exercise Physiology & Sports Medicine

Open Access

Physiological Responses During the Time Limit at 100% of the Peak Velocity in the Carminatti’s Test in Futsal Players

Published Online: 15 Dec 2016
Page range: 91 - 101

Abstract

Abstract

The aim of this study was to investigate the physiological responses during the time limit at the intensity of the peak velocity of the Carminatti’s test (T-CAR). Ten professional futsal players (age, 27.4 ± 5.8 years, body mass, 78.8 ± 8.5 kg, body height, 175.8 ± 6.8 cm, body fat mass, 14.1 ± 2.6%) took part in the study. The players performed three tests, with an interval of at least 48 hours, as follows: the T-CAR to determine the peak velocity and the maximal heart rate; an incremental treadmill protocol to determine the maximal physiological responses; and a time limit running test at the peak velocity reached in the T-CAR. During the last two tests, a portable gas analyzer was used for direct measurement of cardiorespiratory variables. It was shown that the peak velocity was not significantly different from the maximal aerobic speed achieved in the laboratory (p = 0.213). All athletes reached their maximum oxygen uptake during the time limit test. The maximum oxygen uptake achieved during the time limit test was not different from that observed in the laboratory condition (51.1 ± 4.7 vs. 49.6 ± 4.7 ml·kg-1·min-1, respectively, p = 0.100). In addition, Bland and Altman plots evidenced acceptable agreement between them. On average, athletes took ~140 s to achieve maximum oxygen uptake and maintained it for ~180 s. Therefore, the peak velocity intensity can be used as an indicator of maximal aerobic power of futsal athletes and the time limit can be used as a reference for training prescription.

Keywords

  • intermittent field test
  • peak velocity
  • maximal aerobic power
  • time limit
Open Access

The Effect of Specific Sling Exercises on the Functional Movement Screen Score in Adolescent Volleyball Players: A Preliminary Study

Published Online: 15 Dec 2016
Page range: 83 - 90

Abstract

Abstract

The existing data indicate that the result of the Functional Movement Screen (FMS) test influences the likelihood of subsequent injury in professional athletes. Therefore, exercises increasing test scores of the FMS may be useful at various stages of sports activity. This study evaluated the effects of the NEURAC sling exercises method on the FMS test score in teenage volleyball players. The study was conducted on 15 volleyball players aged 14 years. The FMS test was performed three times interspersed with a two-month interval. Between the first and the second assessment, neither additional treatment nor training was applied, while between the second and the third assessment, the participants performed stabilisation exercises based on the NEURAC method. Training was carried out twice a week, for eight weeks. The analysis showed that between the first and the second measurement, no significant differences occurred. The use of specific sling exercises caused a significant improvement in FMS results (p ≤ 0.01) between the first and the third, as well as the second and the third measurement. The applied stabilisation exercises based on the NEURAC method positively influenced the FMS test result in male subjects practicing volleyball. Performance of such exercises also resulted in more than 90% of the subjects having a total FMS test score ≥ 17, which may be important in the prevention of injuries. The preliminary results indicate that this type of exercise should be included in a teenage volleyball training routine.

Keywords

  • stability exercise
  • Functional Movement Screen
  • injury
  • prevention
Open Access

Evaluation of the Effects of Neuromuscular Electrical Stimulation of The Lower Limbs Combined with Pulmonary Rehabilitation on Exercise Tolerance in Patients with Chronic Obstructive Pulmonary Disease

Published Online: 15 Dec 2016
Page range: 75 - 82

Abstract

Abstract

Chronic obstructive pulmonary disease (COPD) is a systemic disease with multiple extrapulmonary manifestations including impeded skeletal muscle function, leading to decreased muscular strength and endurance in patients with COPD. Pulmonary rehabilitation eases the symptoms of the condition and produces increased muscular endurance. Neuromuscular electrical stimulation (NMES) may serve as a treatment alternative to traditional pulmonary rehabilitation. The aim of the study was to assess the effects of NMES combined with pulmonary rehabilitation on exercise tolerance in patients in comparison with pulmonary rehabilitation alone. The subjects included 30 patients with COPD randomly assigned to one of the two groups. The first group consisted of 15 patients who were treated with neuromuscular electrical stimulation at frequency of 35Hz and pulmonary rehabilitation (NMES+RP). The second group comprised 15 patients treated with pulmonary rehabilitation only (RP). Pre- and poststudy assessments were performed. The retrospective evaluation including an exercise tolerance test (i.e. six minute walk test (6MWT)), spirometry and blood gasometry was carried out after 3 weeks. Twenty-eight patients in total completed the study. In the NMES+RP group, an increase in exercise tolerance manifested by a longer distance walked in the 6MWT was observed in comparison to the pulmonary rehabilitation group. No effects of NMES combined with pulmonary rehabilitation on selected spirometric and gasometric parameters in patients with COPD were observed in comparison with traditional pulmonary rehabilitation. The acquired results suggest that NMES of the lower limbs may be applied as an additional form of pulmonary rehabilitation in patients with COPD.

Keywords

  • COPD
  • neuromuscular electrical stimulation
  • exercise tolerance
Open Access

Somatic, Endurance Performance and Heart Rate Variability Profiles of Professional Soccer Players Grouped According to Age

Published Online: 15 Dec 2016
Page range: 65 - 74

Abstract

Abstract

This cross-sectional study compared somatic, endurance performance determinants and heart rate variability (HRV) profiles of professional soccer players divided into different age groups: GI (17–19.9 years; n = 23), GII (20–24.9 years; n = 45), GIII (25–29.9 years; n = 30), and GIV (30–39 years; n = 26). Players underwent somatic and HRV assessment and maximal exercise testing. HRV was analyzed by spectral analysis of HRV, and high (HF) and low (LF) frequency power was transformed by a natural logarithm (Ln). Players in GIV (83 ± 7 kg) were heavier (p < 0.05) compared to both GI (73 ± 6 kg), and GII (78 ± 6 kg). Significantly lower maximal oxygen uptake (VO2max, ml•kg-1•min-1) was observed for GIV (56.6 ± 3.8) compared to GI (59.6 ± 3.9), GII (59.4 ± 4.2) and GIV (59.7 ± 4.1). All agegroups, except for GII, demonstrated comparable relative maximal power output (Pmax). For supine HRV, significantly lower Ln HF (ms2) was identified in both GIII (7.1 ± 0.8) and GIV (6.9 ± 1.0) compared to GI (7.9 ± 0.6) and GII (7.7 ± 0.9). In conclusion, soccer players aged >25 years showed negligible differences in Pmax unlike the age group differences demonstrated in VO2max. A shift towards relative sympathetic dominance, particularly due to reduced vagal activity, was apparent after approximately 8 years of competing at the professional level.

Keywords

  • body composition
  • maximal oxygen uptake
  • vagal activity
  • sports career length, aging
Open Access

Leukocyte Populations are Associated with Heart Rate Variability After a Triathlon

Published Online: 15 Dec 2016
Page range: 55 - 63

Abstract

Abstract

The purpose of this study was to analyze cellular immune components and their association with heart rate variability in triathlon athletes. Twelve athletes were included (age 36.41 ± 5.57 years, body mass 81.84 ± 10.97 kg) and blood samples were taken one week before, immediately, at 2 and 48 hours, and one week after competition. Total lymphocytes and their subpopulations, neutrophils, basophils, eosinophils and monocytes were analyzed. At the same time, heart rate variability was recorded for 30 minutes using Polar Team2®. A significant difference between lymphocyte subpopulations and heart rate variability was found in the different study periods. A positive correlation was found between total lymphocytes and rMSSD (r = .736, p <0.05), CD3+ and rMSSD (r = .785, p <0.05), and CD4+ and rMSSD (r = .795, p < 0.05) at the end of the competition. After one week of competition, a negative correlation was found between eosinophils and MRR, SDNN, pNN50, and rMSSD (p <0.01); and basophils and MRR, SDNN, pNN50, and rMSSD (p <0.01); while a positive correlation was found between CD19+ (B cells) and pNN50 (r = .678, p <0.05). Our results suggest that it is possible to predict the effect of training with regard to the athlete's performance.

Keywords

  • exercise
  • lymphocytes
  • training
  • competition
Open Access

Does the MTHFR A1298C Polymorphism Modulate the Cardiorespiratory Response to Training?

Published Online: 15 Dec 2016
Page range: 43 - 53

Abstract

Abstract

The 5,10-methylenetetrahydrofolate reductase gene (MTHFR) A1298C polymorphic variant is a candidate to explain the individual differences in trainability and response to exercise training. Therefore, the aim of the study was to verify whether the A1298C polymorphism influenced the aerobic and anaerobic performance as well as body and mass composition in young Polish women following low-high impact aerobic exercise training. Two hundred and one women aged 21 ± 1 years (range 19–24) were included in the study. All of them completed a 12-week exercise training program and were measured for selected somatic features, aerobic capacity and cardiorespiratory fitness indices as well as peak anaerobic power and anaerobic capacity, before and after the intervention. A mixed 2 x 2 ANOVA for 20 dependent variables grouped in three categories was conducted. No significant interaction of the genotype with training for body mass and body composition variables was observed. Although, there were three significant genotype x training interactions for maximal oxygen uptake variables, regardless of body mass i.e.: for VO2max (p < 0.05), HRmax (p < 0.0001) and HRAT/HRmax (p < 0.0001). Significantly greater improvement in VO2max was gained by the CC+AC group compared to the AA genotype group. The present results support the hypothesis that individual differences in trainability are at least in part determined by the genetic component and MTHFR A1298C seems to be one of the many polymorphisms involved.

Keywords

  • MTHFR
  • gene polymorphism
  • exercise training

Section III – Sports Training

Open Access

Optimization of Game Formats in U-10 Soccer Using Logistic Regression Analysis

Published Online: 15 Dec 2016
Page range: 163 - 171

Abstract

Abstract

Small-sided games provide young soccer players with better opportunities to develop their skills and progress as individual and team players. There is, however, little evidence on the effectiveness of different game formats in different age groups, and furthermore, these formats can vary between and even within countries. The Royal Spanish Soccer Association replaced the traditional grassroots 7-a-side format (F-7) with the 8-a-side format (F-8) in the 2011-12 season and the country’s regional federations gradually followed suit. The aim of this observational methodology study was to investigate which of these formats best suited the learning needs of U-10 players transitioning from 5-aside futsal. We built a multiple logistic regression model to predict the success of offensive moves depending on the game format and the area of the pitch in which the move was initiated. Success was defined as a shot at the goal. We also built two simple logistic regression models to evaluate how the game format influenced the acquisition of technicaltactical skills. It was found that the probability of a shot at the goal was higher in F-7 than in F-8 for moves initiated in the Creation Sector-Own Half (0.08 vs 0.07) and the Creation Sector-Opponent's Half (0.18 vs 0.16). The probability was the same (0.04) in the Safety Sector. Children also had more opportunities to control the ball and pass or take a shot in the F-7 format (0.24 vs 0.20), and these were also more likely to be successful in this format (0.28 vs 0.19).

Keywords

  • soccer
  • adaptation
  • child
  • observational methodology
  • logistic regression
Open Access

Mechanical Differences between Barbell and Body Optimum Power Loads in the Jump Squat Exercise

Published Online: 15 Dec 2016
Page range: 153 - 162

Abstract

Abstract

This study compared the values of bar-peak force (PFBar) and power (PPBar), body-peak force (PFBody) and power (PPBody) and bar-mean propulsive power (MPPBar) in different jump-squat (JS) conditions: unloaded condition (UC); bar-loaded condition (BLC) and optimum bar-MPP condition (OBC). Twenty-five soccer players performed the JS using a bar with negligible mass (UC), using the Smith-machine bar (BLC) and using the load capable of maximizing the bar-MPP (OBC). The PFBody was significantly higher in the UC (2847.9 ± 489.1 N) than in the OBC (2655.4 ± 444.3 N). The UC presented greater PPBody (3775.9 ± 631.5 W) than the BLC (3359.7 ± 664.3 W) and OBC (3357.8 ± 625.3 W). The OBC presented higher values of PFBar, PPBar and MPPBar (676.2 ± 109.4 W) than the BLC (MPPBar = 425.8 ± 53.7 W) (all p < 0.05). In the OBC (compared to the UC), the body peak-power presented a reduction of ≈ 11%, while generating bar-power output from ≈ 59 to 73% higher than the BLC. While the fact that the body-peak power is maximized in the UC denotes a mechanical phenomenon, the bar-optimum load represents an intensity at which both components of the power equation (force and velocity) are optimized. This has important implications for sports training.

Keywords

  • optimal loads
  • muscle power
  • ballistic
  • plyometrics
  • neuromuscular
Open Access

Performance Assessment in Water Polo Using Compositional Data Analysis

Published Online: 15 Dec 2016
Page range: 143 - 151

Abstract

Abstract

The aim of the present study was to identify groups of offensive performance indicators which best discriminated between a match score (favourable, balanced or unfavourable) in water polo. The sample comprised 88 regular season games (2011-2014) from the Spanish Professional Water Polo League. The offensive performance indicators were clustered in five groups: Attacks in relation to the different playing situations; Shots in relation to the different playing situations; Attacks outcome; Origin of shots; Technical execution of shots. The variables of each group had a constant sum which equalled 100%. The data were compositional data, therefore the variables were changed by means of the additive log-ratio (alr) transformation. Multivariate discriminant analyses to compare the match scores were calculated using the transformed variables. With regard to the percentage of right classification, the results showed the group that discriminated the most between the match scores was “Attacks outcome” (60.4% for the original sample and 52.2% for cross-validation). The performance indicators that discriminated the most between the match scores in games with penalties were goals (structure coefficient (SC) = .761), counterattack shots (SC = .541) and counterattacks (SC = .481). In matches without penalties, goals were the primary discriminating factor (SC = .576). This approach provides a new tool to compare the importance of the offensive performance groups and their effect on the match score discrimination.

Keywords

  • performance profile
  • observational analysis
  • statistical data analysis
Open Access

Physical Performance During Water-Polo Matches: The Effect of the Players’ Competitive Level

Published Online: 15 Dec 2016
Page range: 135 - 142

Abstract

Abstract

The purpose of the study was to compare playing intensity and performance changes within a water-polo match in players of different competitive levels. High-level (n = 7) and lower-level (n = 7) players performed a progressively increasing speed test of 5 x 200 m swimming and speed corresponding to lactate concentration of 4.0, 5.0 and 10.0 mmol•l-1 was calculated. Repeated sprint ability (8 x 20 m) was tested at pre-, the middle and post-match and a 400 m swimming test was completed at pre and post in five water-polo matches. A t-test and a two-way ANOVA were used for statistical analysis. High-level compared to lower-level players presented higher speed corresponding to lactate concentration of 4.0 and 5.0 mmol•l-1 (p < 0.05). Regardless of the sports level, the mean heart rate was reduced towards the end of the match. High-level players completed a shorter amount of match time with the heart rate lower than 85% of the peak heart rate (p < 0.05). However, when the speed corresponding to lactate concentration of 4.0 mmol•l-1 was used as a covariate, no differences were observed in the heart rate between groups. Both groups decreased repeated sprint and 400 m performance at post- compared to pre-match by 7 ± 3% and 7 ± 4%, respectively. High-level compared to lower-level players showed better performance in repeated sprints at the middle (p < 0.01) and in pre-, post-match 400 m tests (p < 0.01). It was concluded that high-level compared to lower-level players completed the match at a higher playing intensity and presented a lower performance decrement across the match as a result of their higher aerobic endurance.

Keywords

  • team-sports
  • physical fitness
  • match-induced fatigue
Open Access

The Effects of Modifying the Distance of the Penalty Shot in Water Polo

Published Online: 15 Dec 2016
Page range: 127 - 133

Abstract

Abstract

The aim of this study was to determine the effects of changing the distance of the penalty shot in water polo from 4 to 5 m. While a shorter distance made the penalty shot more effective, it also reduced the use of this sanction. A total of 192 matches played in the 2003 and 2007 Water Polo World Championships were recorded. The sample included 278 penalty shots in both tournaments. Notational analysis using a longitudinal correlational and descriptive design was employed to determine whether a longer distance increased the number of sanctioned penalties (81 vs 197) and caused a non-significant decrease in scoring efficiency (7.4%) with significant differences in the relationship between the area and the type of a shot, with less centre and power shots (14.8% vs 7.1%) observed and predominance of bounce shots to the right of the goal posts. The rule change prompted more penalties, produced changes in shot direction as well as the type of a shot, and yielded a decrement of 7.4% in scoring efficiency.

Keywords

  • water polo
  • rules modification
  • penalty shot
Open Access

Evolution of Determinant Factors of Repeated Sprint Ability

Published Online: 15 Dec 2016
Page range: 115 - 126

Abstract

Abstract

The aim of this study was to investigate the changes in the relationships between repeated sprint ability (RSA) and anthropometric measures as well as fitness qualities in soccer players. Twenty-one professional soccer players performed several anthropometric and physical tests including countermovement vertical jumps (CMJs), a straight-line 30 m sprint (T30), an RSA test (6 x 20 + 20 m with 20 s recovery), a progressive isoinertial loading test in a full squat, a Yo-Yo Intermittent Recovery Test Level-1 (YYIRT-1) and a 20 m shuttle run test (20mSRT). The mean (RSAmean), the fastest (RSAbest), each single sprint time, and the percentage in a sprint decrease (%Dec) in the RSA test were calculated. RSAbest correlated significantly with RSAmean (r = .82) and with all single sprints (p < 0.05), showing a downward trend as the number of sprints performed increased. No significant relationship was observed between the %Dec and RSA performance. CMJs and the T30 also showed a correlation with RSA performance, whereas lower limb strength did not show any relationship with RSA performance. RSAmean showed significant (p < 0.05) relationships with body mass (r = .44), adiposity (r = .59) and the YYIRT-1 (r = -.62), increasing as the number of repeated sprints increased. The 20mSRT showed minimal relationships with RSA performance. In conclusion, maximal sprint capacity seems to be relevant for the RSA performance, mainly in the first sprints. However, high intermittent endurance capacity and low adiposity might help enhance the RSA performance when increasing the number of repeated sprints.

Keywords

  • anthropometrics
  • repeated explosive efforts
  • strength
  • sprinting
  • intermittent endurance
  • soccer
Open Access

Effects of Fatigue on Throwing Performance in Experienced Team Handball Players

Published Online: 15 Dec 2016
Page range: 103 - 113

Abstract

Abstract

The purpose of this study was to investigate the effect of central and peripheral physiological fatigue on throwing accuracy and ball release velocity in team handball. Twenty male subjects (age 24.7 ± 3.9 yrs, body mass 88.5 ± 5.0 kg, body height 1.86 ± 0.05 m, training experience 12.7 ± 3.8 yrs) from one handball team participated in this study. The participants completed four sets of eight laps of a circuit that consisted of specific team handball drills/exercises, with decreasing recovery times between the laps in each set in order to induce physiological fatigue. Duration of the recovery intervals determined the description of the effort made in each set: “light" (80 s recovery between laps), “moderate" (40 s), “hard" (20 s) and “very hard" (10 s). A heart rate, concentration of lactate in blood and the rate of perceived exertion (RPE) were recorded. Ball velocity and accuracy were measured after each set and they both decreased during a fatigue protocol. However, accuracy only decreased significantly in the end of the protocol, while ball release was already affected after the first round of the protocol. The results substantiate the initial hypothesis and confirm that both throwing accuracy and ball release velocity decrease significantly as physiological fatigue increases. These variables began to decrease when the fatigue quantification values were high or very high. The findings can be used by coaches to develop training programs to teach players how to identify fatigue thresholds and combat the effects of fatigue through decision-making skills at critical game moments.

Keywords

  • specific training
  • physiological fatigue
  • heart rate
  • blood lactate
  • rating of perceived exertion

Section IV – Behavioural Sciences in Sport

Open Access

Soccer Players Cultural Capital and Its Impact on Migration

Published Online: 15 Dec 2016
Page range: 195 - 206

Abstract

Abstract

The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player’s success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player’s previous attitudes and/or behaviours (habitus), significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu’s theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players’ cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach’s alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1) had 2.2 times and the second factor (F8) had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better “success conditions” in the talent development of young players.

Keywords

  • social cultural factors
  • soccer
  • talent development
Open Access

Quality Perception of the 2012 World Indoor Athletics Championships

Published Online: 15 Dec 2016
Page range: 181 - 194

Abstract

Abstract

The objective of this study was to compare the views of spectators concerning the quality perception of the World Indoor Athletics Championships. The study group consisted of 568 spectators who watched the events. A measurement scale of event quality in spectator sports (SEQSS) developed by Ko et al. (2011) was used as a data collection tool in the study. In order to determine the views of the spectators concerning the quality of the Indoor Athletics Championships, the dimensions constituting the scale were compared according to the demographic features of the sample group. As a consequence, important differences in most of the dimensions of the scale were revealed with respect to the demographic data of the subjects. The most relevant finding of the study is that the dimension of “physical environment quality”, which is one of the dimensions constituting the event quality, differed significantly in all comparisons that were made according to demographic features.

Keywords

  • event quality
  • spectator
  • service quality
Open Access

Developing Talented Soccer Players: An Analysis of Socio-Spatial Factors as Possible Key Constraints

Published Online: 15 Dec 2016
Page range: 227 - 236

Abstract

Abstract

Most studies on the identification and development of soccer talent have been one-dimensional in nature. Although some multi-dimensional analyses have been conducted, few research studies have assessed in any depth the socio-spatial factors influencing talent development. The aim of this particular study was to analyse variations in the international representation of clubs (n = 821) and countries (n = 59) in the development of players who took part in the 2014 FIFA Soccer World Cup. Clubs and countries were ranked and divided into quartiles according to the number of players developed between the ages of 15 and 21 (clubs and countries that developed players for at least three years between these ages) and the number of official league matches played by these players up to the age of 23. Significant variations were observed between clubs in terms of the number of developed players who took part in the World Cup and the number of official league matches played by these players up to the age of 23 (p < .05), and also between countries (p < .05). The findings reveal the need to carry out more in-depth studies into the type of training and competition engaged in by elite players in the period of development between the ages of 15 and 21. It may be the case that these factors are potentially decisive socio-spatial constraints in the development of soccer talent.

Keywords

  • social factors
  • talent development
  • training
  • ecological dynamics
Open Access

The Chronotype of Elite Athletes

Published Online: 15 Dec 2016
Page range: 219 - 225

Abstract

Abstract

The aims of this study were (i) to compare the chronotype distribution of elite athletes to a young adult population and (ii) to determine if there was a tendency for athletes to select and/or participate in sports which suited their chronotype. A total of 114 elite athletes from five sports (cricket, cycling, hockey, soccer and triathlon) participated in this study. The participants’ chronotype, sleepiness, sleep satisfaction and sleep quality were determined using the Horne and Östberg Morningness and Eveningness questionnaire, the Epworth Sleepiness Scale and questions concerning their sleep satisfaction and quality. All questionnaires were administered during a typical training phase that was not in the lead up to competition and/or post competition. No differences between chronotype group for sleepiness, sleep satisfaction or sleep quality were found. There was a significantly higher proportion of triathletes that were morning and intermediate types compared to the control group χ2 (2) = 7.5, p = 0.02. A significant relationship between sport and chronotype group (χ2(4)=15.9, p = 0.04) was observed, with a higher frequency of morning types involved in sports that required morning training. There was a clear indication that athletes tended to select and pursue sports that suited their chronotype. This was evident by the amount of morning types involved in morning sports. Given that athletes are more likely to pursue and excel in sports which suit their chronotype, it is recommended that coaches consider the athlete’s chronotype during selection processes or if possible design and implement changes to training schedules to either suit the athletes’ chronotype or the timing of an upcoming competition.

Keywords

  • sleep
  • circadian preference
  • sport
Open Access

A Comparison of Physical Education Students’ Motivation Using Polish and Turkish Versions of the Academic Motivation Scale

Published Online: 15 Dec 2016
Page range: 207 - 218

Abstract

Abstract

Motivation is an important phenomenon in the realm of education, particularly in the university fields connected with physical education and sport, where it is necessary to accommodate and balance intellectual abilities and physical fitness. The present study tested motivation levels among university students in the fields connected with physical education and sport in Poland and Turkey. It was based on the Self-Determination Theory (Deci and Ryan, 1985), namely intrinsic motivation, extrinsic motivation and amotivation which impact human behaviour. The Academic Motivation Scale was used (Vallerand et al., 1992). The aims of the study were twofold, first, to crossculturally validate Polish and Turkish versions of the Academic Motivation Scale and second, to identify and compare the motivation to study depending on nationality and gender. Both Polish and Turkish versions of the questionnaire were validated and converted to a four-factorial structure. The findings indicated that Polish and Turkish students’ motivation especially differed in amotivation and intrinsic motivation to know and experience stimulation. Moreover, Turkish female students proved to be at the lowest estimate of amotivation.

Keywords

  • intrinsic motivation
  • extrinsic motivation
  • physical education and sport

Section V – Book Review

Open Access

Periodization in Team Sport Games - A Review of Current Knowledge and Modern Trends in Competitive Sports

Published Online: 15 Dec 2016
Page range: 173 - 180

Abstract

Abstract

The main goal of this study was to present a review of current knowledge and modern trends in periodization of the training process in team sports. The research objectives were: an analysis of various aspects of periodization of the annual training cycle for elite athletes practicing team sport games, an attempt to determine both the examined and unexamined issues related with periodization of training as well as to indicate directions for further research, and finally, presentation of different training loads and competitions in micro-, meso- and macrocycles. The research consisted of the analysis and generalization of the bibliography, methods of monitoring training and competition loads of the Polish national U17 female soccer team in the seasons 2011/2012 and 2012/2013, as well as of the female basketball division one club in the season 2014/2015. Findings of the present study indicate resolved as well as unresolved aspects of annual training cycle periodization in team sport games and provide information on the types of training and competitive workload planning in micro-, meso- and macrocycles.

Keywords

  • team sport games
  • periodization
  • training loads
  • training cycles

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