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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 71 (2020): Issue 1 (January 2020)

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

Search

26 Articles

Short Communication

Open Access

Understanding Player Load: Meanings and Limitations

Published Online: 31 Jan 2020
Page range: 5 - 9

Abstract

Abstract

We present a critical reflection on the mechanical variable Player Load, which is based on acceleration data and commonly used in sports. Our motivation to write this paper came from the difficulties that we encountered in the calculation and interpretation of Player Load using our own data, since we did not use the Catapult Sports equipment, which is a merchandise of the company that proposed this variable. We reviewed existing literature in order to understand Player Load better; we found many inconsistencies in PL calculation methods and in the meanings attached to it. Accordingly, this paper presents a brief discussion on the meanings that have been assigned to Player Load, its limitations, and the lack of clear and complete information about Player Load calculation methods. Moreover, the use of arbitrary units and different practical meanings in the literature has associated Player Load with many physical quantities, thereby resulting in difficulties in determining what Player Load measures within the context of sports. It seems that Player Load is related to the magnitude of changes in acceleration, but not the magnitude of acceleration itself. Therefore, coaches and sports scientists should take this information into account when they use Player Load to prescribe and monitor external loads. We concluded that a deeper discussion of Player Load as a descriptor of external load is warranted in the sports sciences literature.

Key words

  • acceleration
  • external training load
  • mechanical variables

Section I - Kinesiology

Open Access

The Effectiveness of a Dry-Land Shoulder Rotators Strength Training Program in Injury Prevention in Competitive Swimmers

Published Online: 31 Jan 2020
Page range: 11 - 20

Abstract

Abstract

Competitive swimmers usually undergo large mileage of daily training, in which propulsive force is produced mainly by the upper limbs. Some studies claim that dry-land shoulder rotators injury prevention programs before the in-water swim practice are paramount. However, the effect of shoulder strengthening prior to water training is unclear. This study aimed to analyse the acute effects of training programs conducted on dry land with the goal of preventing shoulder rotators injuries. A group of young swimmers (N = 23) was recruited to participate in this research. The peak torques of shoulder internal and external rotators were assessed before and after the completion of the compensatory strength training program. The isokinetic assessment was performed using two different protocols: 3 repetitions at 60/s and 20 repetitions at 180/s. Except for a trivial reduction in strength after the training program, there were no other significant differences in any of the studied variables (shoulders rotators endurance, strength and muscle balance). All results showed trivial to small effect sizes. Our findings suggest that a compensatory strength training program does not have a significant acute effect on the strength, endurance and muscle balance of shoulder rotators in young swimmers.

Key words

  • swimming
  • isokinetic strength
  • shoulder rotators
  • acute effects
Open Access

Development and Validation of a Checklist to Assess Proficient Performance of Basketball Straight Speed Dribbling Skill

Published Online: 31 Jan 2020
Page range: 21 - 31

Abstract

Abstract

The aim of this study was to develop and validate a checklist to assess proficient performance of basketball straight speed dribbling skill. The sample was composed of 100 children and adolescents between 7 and 15 years of age with and without structured practice in basketball. The validation process tested the validity domain, decision, tendencies, reliability, responsiveness, and objectivity. The results show that the checklist contains criteria that represent the speed dribbling skill and is sensible to distinguish between different proficiency levels of performance. The results also expressed high reliability and objectivity (intra and inter-rater). In light of the findings, we concluded that the checklist can be used to reliably analyze performance and evaluate the process of learning and development of the straight speed dribbling skill.

Key words

  • sport skills
  • measurement
  • motor performance
  • team sport games
Open Access

Intra-Trial Reliability and Usefulness of Isometric Mid-Thigh Pull Testing on Portable Force Plates

Published Online: 31 Jan 2020
Page range: 33 - 45

Abstract

Abstract

The aim of this study was to assess the intra-trial reliability and usefulness of portable force plates and a customised Isometric Mid-Thigh Pull rig. Twenty males (age: 24.1 ± 2.5 years, body height: 177.7 ± 0.09 cm, body mass: 88.4 ± 17.9 kg) with weightlifting experience ± 12 months attended 1 familiarisation session and 1 testing session where 4 isometric mid-thigh pulls were performed. Maximum force, absolute peak force (PF), relative PF, allometrically scaled PF, and force (150, 200, 250 ms) were deemed reliable (ICC ≥ 0.91 and CV ≤ 9.8%) based on predetermined criteria (ICC ≥ 0.8 and CV ≤ 10%). The impulse and the rate of force development (RFD) were deemed unreliable (ICC ≤ 0.91 and CV ≥ 10 %) at all time points. Maximum force, absolute PF, relative PF to body weight and body mass, rand allometrically scaled PF, had a typical error (TE) lower than the smallest worthwhile change small effect (SWC0.2) and moderate effect (SWC0.5) and were rated as good with regard to usefulness. The TE for force at selected time points (150, 200, 250 ms) was also higher than the SWC0.2, achieving a rating of marginal, but TE was higher than SWC0.5, achieving a rating of good with regard to usefulness. Portable force plates and customised rigs can reliably determine peak force and force output at different time points and for detecting the SWC in maximum and absolute force measures, greater familiarisation may be required to establish reliability of other variables such as the impulse and the RFD.

Key words

  • isometric strength
  • force time curve
  • mid-thigh pull
  • performance testing
Open Access

Jumping-based Asymmetries are Negatively Associated with Jump, Change of Direction, and Repeated Sprint Performance, but not Linear Speed, in Adolescent Handball Athletes

Published Online: 31 Jan 2020
Page range: 47 - 58

Abstract

Abstract

The aim of the present study was to determine the association of multi-directional jumping asymmetries with measures of physical performance. Forty-two youth handball athletes (age: 16.0 ± 1.3 years; body height: 174.11 ± 7.3 cm; body mass: 70.49 ± 13.3 kg) performed a mid-season fitness test battery consisting of single leg countermovement, lateral and broad jump tests, two change of direction speed (CODS) tests, an 8 x 10 m repeated sprint test, and a 20 m sprint. The Kappa coefficient showed only ‘slight’ levels of agreement (K range = -0.05 to 0.15), indicating that asymmetries rarely favoured the same side during each of the jump tests. The single leg countermovement jump showed significantly (p = 0.006) larger asymmetries (11.2 ± 8.4) than the broad jump (6.4 ± 4.6) and significant correlations were present between jumping asymmetries and jump (r = -0.32 to -0.52), CODS (r = 0.31 to 0.32) and repeated sprint (r = 0.35 to 0.40) performance. The findings of the present study highlight the independent nature of jumping asymmetries and associations with measures of physical performance. Practitioners are encouraged to use multiple tests to detect existing side differences and consider appropriate training interventions for the reduction of inter-limb asymmetries.

Key words

  • handball
  • inter-limb differences
  • performance reduction
  • youth athletes
Open Access

The Effects of Compression Garments on Stability and Lower Limb Kinematics During a Forward Lunge

Published Online: 31 Jan 2020
Page range: 59 - 68

Abstract

Abstract

Compression garments have been used to minimise injury risk, through improvements in stability and joint positioning; yet, it is unclear whether there is an optimal length or tightness of these garments that may maximise observed benefits. This study measured the effect of three different garment types, at two different tightness levels, on lower extremity stability and alignment during a forward lunge movement. Sixteen healthy adults (7 female, 9 male; 24.3 ± 2.9 years) were recruited as participants. Stability of the lead foot, as well as lower body joint kinematics, were recorded using an Oqus 12-camera system, surrounding participants as they executed three forward lunges onto a Matscan pressure mat under seven compression conditions (Control, Light/Heavy Calf, Light/Heavy Socks, Light/Heavy Leggings). Mean minimum time-to-boundary (mmTtB) (derived from centre of pressure measures) and frontal plane kinematics (lateral pelvic tilt, knee valgus, ankle inversion/eversion) were used to assess the effect of garment tightness and length on lunge stability and joint alignment, respectively. A significant effect of tightness on mmTtB was observed (F(1,105) = 8.192; p = .005, η2 = .072), with Heavy garments eliciting longer mmTtB compared to their corresponding Light (-.18 ± .06 s; p = .015) or Control (-.28 ± .09 s; p = .007) conditions. No significant effects of garment tightness or length on lower body kinematics were evident. The results of this study suggest stability during a forward lunge is improved through the use of tight-fitted compression garments.

Key words

  • time-to-boundary
  • proprioception
  • injury
  • joint alignment
Open Access

Lower Extremity Stiffness in Collegiate Distance Runners Pre- and Post-Competition

Published Online: 31 Jan 2020
Page range: 69 - 77

Abstract

Abstract

Previous evidence has suggested that there is a relationship between leg stiffness and improved running performance. The purpose of this investigation was to determine how leg stiffness of runners was influenced in the 24 and 48 hour period following a cross country race. Twenty-two collegiate cross-country runners (13 males, 9 females, 19.5 ± 1.4 yr) were recruited and participated in the study. Leg stiffness was assessed 24 hours before and after a race as well as 48 hours post-race. Three jumping protocols were conducted: 1) a static jump, 2) a countermovement jump, and 3) a vertical hopping test. Two embedded force plates (1000 Hz) were utilized to measure ground reaction forces for each test and a metronome was utilized to maintain hopping frequency (2.2 Hz). A significant main effect was found for a static jump, a countermovement jump and leg stiffness. Leg stiffness was significantly reduced 24 hours post-race (pre-race 36.84 kN·m-1, 24h post 33.11 kN·m-1, p < 0.05), but not 48 hours post-race (36.30 kN·m-1). No significant differences were found in post-hoc analysis for the squat jump, countermovement jump height and the eccentric utilization ratio. Following a cross-country race, leg stiffness significantly declined in a group of collegiate runners in the immediate 24 hours post-race, but returned to baseline 48 hours post-race. Sport scientists and running coaches may be able to monitor leg stiffness as a metric to properly prescribe training regiments.

Key words

  • hopping
  • fatigue
  • running performance
  • neuromuscular characteristics
  • stretch-shortening cycle (SSC)

Section II - Exercise Physiology & Sports Medicine

Open Access

Nutritional Recommendations for Physique Athletes

Published Online: 31 Jan 2020
Page range: 79 - 108

Abstract

Abstract

The popularity of physique sports is increasing, yet there are currently few comprehensive nutritional guidelines for these athletes. Physique sport now encompasses more than just a short phase before competition and offseason guidelines have recently been published. Therefore, the goal of this review is to provide an extensive guide for male and female physique athletes in the contest preparation and recovery period. As optimal protein intake is largely related to one’s skeletal muscle mass, current evidence supports a range of 1.8-2.7 g/kg. Furthermore, as a benefit from having adequate carbohydrate to fuel performance and activity, low-end fat intake during contest preparation of 10-25% of calories allows for what calories remain in the “energy budget” to come from carbohydrate to mitigate the negative impact of energy restriction and weight loss on training performance. For nutrient timing, we recommend consuming four or five protein boluses per day with one consumed near training and one prior to sleep. During competition periods, slower rates of weight loss (≤0.5% of body mass per week) are preferable for attenuating the loss of fat-free mass with the use of intermittent energy restriction strategies, such as diet breaks and refeeds, being possibly beneficial. Additionally, physiological and psychological factors are covered, and potential best-practice guidelines are provided for disordered eating and body image concerns since physique athletes present with higher incidences of these issues, which may be potentially exacerbated by certain traditional physique practices. We also review common peaking practices, and the critical transition to the post-competition period.

Key words

  • physique
  • bodybuilding
  • nutrition
  • contest preparation
  • competition recovery
Open Access

Comparison of Morphological Profiles and Performance Variables Between Female Volleyball Players of the First and Second Division In Portugal

Published Online: 31 Jan 2020
Page range: 109 - 117

Abstract

Abstract

Knowledge of players’ anthropometric profiles may contribute to a better understanding of the differences between their performance levels. For example, vertical jump height, which is a major indicator of a volleyball player’s performance, is influenced by favorable anthropometric variables. This study’s aim was to describe anthropometric profiles of elite female volleyball players competing in the 1st and 2nd divisions in Portugal and to link these profiles with performance skills such as jump height obtained during blocking and spiking actions. Fifty-nine volleyball players were analyzed according to their competitive level, forming three independent groups: GA (n = 20, A1 division, ranked first), GB (n = 21, A1 division, ranked last) and GC (n = 18, A2 division). Anthropometric data collected included body mass and height, arm span, seven skinfolds (triceps, biceps, subscapular, suprailiac, abdominal, thigh and calf), four body perimeters (relaxed brachial, contracted brachial, thigh and calf), and two body diameters (humeral and femoral). Performance data included the height obtained during block and spike actions. Significant differences were found between groups (GA/GB from A1 and GC from A2). Players in the GA had the highest body mass (68.05 ± 6.62 kg, p < 0.05), body height (176.35 ± 6.21 cm, p < 0.05), arm span (177.59 ± 6.09 cm, p < 0.05), lean mass (53.51 ± 4.94 kg, p < 0.05) and vertical jump heights (block: 0.36 ± 0.06 m and spike: 0.43 ± 0.05 m, p < 0.05). As expected, the fat mass percentage of GA players was the lowest (21.30 ± 2.61%). The results suggest that anthropometric profiles of volleyball players may vary according to the competitive level. The higher body mass, body height, arm span, and lean mass presented by GA players in comparison with GC players suggest these variables are important for top-level performance, since these athletes also exhibited higher jump heights. Variables such as height and arm span have a considerable genetic influence and could be important for early talent identification in volleyball. Other variables such as body mass, lean mass and vertical jump performance are more complex, since they also reflect the effects of environmental and training conditions.

Key words

  • anthropometric characteristics
  • volleyball
  • somatotype
  • vertical jump
Open Access

Roller Massage: Comparing the Immediate Post‐Treatment Effects Between an Instructional Video and a Self‐Preferred Program Using Two Different Density‐Type Roller Balls

Published Online: 31 Jan 2020
Page range: 119 - 129

Abstract

Abstract

The aims of this study were to (1) compare the immediate post-treatment effects of an instructional video versus a self-preferred program on the hip range of motion and a pressure pain threshold using two different density roller balls, and (2) compare the effects of the two roller balls on those variables. Forty adults were randomly allocated into four groups: (1) MB1-video, (2) MB1-self-preferred, (3) MBX-video, and (4) MBX-self-preferred. Participants followed a video or a self-preferred program using either a moderate (MB1) or a hard (MBX) density ball. Main outcomes were passive hip internal rotation, external rotation, and a pressure pain threshold. For MB1, the video produced greater outcomes than the self-program for external rotation (10◦ versus 2◦), internal rotation (7◦ versus 2◦), and the pain threshold (210 kPa versus 44 kPa). For MBX, the video produced greater outcomes than the self-program for external rotation (8◦ versus 1◦), internal rotation (5◦ versus 1◦), and the pain threshold (184 kPa versus 30 kPa). When comparing roller balls, the MB1 produced greater outcomes than the MBX for external rotation (10◦ versus 8◦), internal rotation (7◦ versus 5◦), and the pain threshold (210 kPa versus 184 kPa) with the video. For the self-preferred program, the MB1 produced greater outcomes for external rotation (2◦ versus 1◦), internal rotation (2◦ versus 1◦), and the pain threshold (44 kPa versus 30 kPa). The instructional video and a moderate density ball produced greater immediate post-treatment outcomes than the self-program and a hard density ball. Professionals should consider using the video to teach technique and match clients to a specific density-type roller ball.

Key words

  • foam
  • massage
  • myofascial
  • pain
  • release
Open Access

Muscle Thickness During Core Stability Exercises in Children and Adults

Published Online: 31 Jan 2020
Page range: 131 - 144

Abstract

Abstract

Core stability exercises are regular part of exercise programs for asymptomatic individuals across ages. The purpose of this study was to examine deep abdominal and multifidus muscle thickness in children and adults and to determine reliability of the rehabilitative ultrasound (RUSI) imaging. Transversus abdominis and lumbar multifidus thickness at rest and during core stability exercise were examined in pre-pubertal children (N = 23), adolescents (N = 20), young adults (N = 21) and middle-aged adults (N = 22). Thirty-nine participants were re-tested one week after to establish reliability. Muscle thickness at rest was lower in children and adolescents compared with young and middle-aged adults (p < 0.008). Young adults displayed the highest relative transversus abdominis thickness upon contraction (p < 0.008). Lumbar multfidus contraction thickness was greater in young-adults than middle-aged adults and pre-pubertal children (p < 0.008), but it was similar between young-adults and adolescents (p > 0.008). Reliability was high for both muscles (ICC3,3 = 0.76 - 0.99). The age-related differences in muscle thickness indicate that core stability exercises may be beneficial for children and middle-aged adults.

Key words

  • childhood
  • musculoskeletal ultrasound
  • repeatability
  • core exercise
  • core stability
Open Access

Eating Habits and Body Composition of International Elite Soccer Referees

Published Online: 31 Jan 2020
Page range: 145 - 153

Abstract

Abstract

Soccer referees are a specific group of the athletes’ population whose careers peak from 30 to 45 years old. An athlete's performance is not only determined by physical training but also by a lifestyle, e.g. eating habits. The purpose of this study was to verify current eating habits and resulting body composition of a group of elite international soccer referees. At an international FIFA seminar 60 elite international soccer referees (aged 39.2 ± 4.2 years) were enrolled. A body composition assessment was performed with skinfold thickness and bio impedance analysis, while eating habits were evaluated with a multi-pass 24-hour dietary recall. The body composition showed a normal weight condition with a fat content of 11.4 ± 2.5%. Macronutrients showed a low level of carbohydrates (43.6 ± 5.4%) and a high level of fat (40.0 ± 4.5%). Micronutrients showed a low level of calcium, potassium, zinc, magnesium, iodine, vitamin B12 and vitamin B9. Even though their body composition was within the normal range, the current eating habits of elite international soccer referees did not appear to follow the nutrition guidelines. Therefore, it would be advisable to provide knowledge on nutrition for this particular category of sports subjects, an individualized nutritional plan would be advisable, in order to achieve and maintain better performance and appropriate body composition for their role.

Key words

  • match officials
  • soccer
  • fat mass
  • micronutrients
  • macronutrients
Open Access

Hormonal Response to Incremental and Continuous Exercise in Cyclists with Left Ventricle Hypertrophy

Published Online: 31 Jan 2020
Page range: 155 - 166

Abstract

Abstract

The aim of this study was to assess the effects of incremental and continuous exercise on the concentration of insulin-like growth factor-1 (IGF-1), growth hormone (GH), testosterone (T), and cortisol (C), as well as to investigate whether increased cardiac dimensions in cyclists were related to changes in these hormones and cardiac biomarkers. The study included 30 elite cyclists divided into two groups, i.e., athletes with left ventricle hypertrophy (a LVH group), and a control group (CG) without LVH. The study protocol included performance of a standard incremental exercise (IncEx) test to measure athletes’ maximum power (Pmax), maximum oxygen uptake (VO2max), and lactate threshold (LAT). The IncEx test results were then used to determine the intensity of the continuous exercise (ConEx) test which was performed after the 1-week washout period. Cyclists with LVH and without LVH did not differ in resting hormone concentrations and cardiac biomarkers levels. There was a significant effect of exercise on serum IGF-1 levels (p < 0.05) in the LVH group and a combined effect of the type of exercise and LVH on IGF-1 (p < 0.05). Cyclists with LVH demonstrated higher post exercise T levels recorded in response to exercise compared to the CG (p < 0.01). Significantly higher serum T levels were observed in response to ConEx compared to IncEx in the LVH group and the CG (p < 0.05 and p < 0.05, respectively). In the LVH group, a significant positive correlation between the post-exercise T/C ratio and left ventricular mass index was observed (r = 0.98, p < 0.01). There were no effects of heart hypertrophy on cardiac standard biomarkers. Incremental and continuous exercise caused a marked increase in steroid hormone concentrations and moderate strengthening of insulin growth factors effects. Regular incremental exercise seems to induce beneficial cardiac adaptations via significant increases in the concentration of anabolic factors compared to the same training mode yet with constant exercise intensity.

Key words

  • hormones
  • cardiac markers
  • myocardium
  • cycling
  • endurance exercise

Section III - Sports Training

Open Access

Effect of an Inside Floater on Soccer Players Tactical Behaviour in Small Sided and Conditioned Games

Published Online: 31 Jan 2020
Page range: 167 - 177

Abstract

Abstract

The aim of this study was to verify the effect of an inside floater on soccer players’ tactical behaviour in small-sided and conditioned games (SSCGs). The sample comprised 54 Brazilian top-level academy players. The instrument used to assess players’ tactical behaviour was the System of Tactical Assessment in Soccer (FUT-SAT). Tactical behaviour was analysed through the number of tactical actions and the percentage of correct actions regarding the core tactical principles of soccer. Repeated measures test was used to compare tactical behaviour between games (SSCGs) with and without an inside floater. Pearson’s r was used to verify the effect size of the inside floater on tactical behaviour. As for tactical actions, SSCGs with an inside floater displayed significantly lower means for the tactical principles of penetration (2.76 ± 1.63; p < .001), delay (6.11 ± 2.68; p < .018), defensive coverage (1.64 ± 1.14; p < .001) and significantly higher means for the tactical principle of defensive unity (14.98 ± 4.57; p < .032). With respect to the percentage of correct actions, SSCGs with an inside floater displayed significantly lower means for all tactical principles, except for offensive coverage (90.5 ± 18.48; p < 1.000). It was concluded that the inside floater allowed players to modify their behaviour in such a way that they adapted to the constraints imposed by the presence of an inside floater. Furthermore, the inside floater provided more difficulty for players, and thus may be considered an important task constraint to be added in SSCGs.

Key words

  • soccer
  • task constraint
  • training
  • youth soccer players
  • core tactical principles
Open Access

Technical Performance and Perceived Exertion Variations Between Small-Sided Basketball Games in Under-14 and Under-16 Competitive Levels

Published Online: 31 Jan 2020
Page range: 179 - 189

Abstract

Abstract

The aim of this study was twofold: i) to compare the rate of perceived exertion (RPE) and the frequencies of technical actions per minute in different small-sided games (SSGs) between under-14 and under-16 age groups, and ii) to compare the RPE and the frequencies of technical actions per minute between 1 x 1, 2 x 2, 3 x 3, 4 x 4 and 5 x 5 formats within age groups. Twenty young male basketball players from the same club (N = 10, from under-14; N = 10, from under-16) competing at the national level voluntarily participated in this study. Five different SSGs (1 x 1, 2 x 2, 3 x 3, 4 x 4 and 5 x 5) were played twice on courts of the same relative area and were compared in terms of the RPE and technical actions. The number of technical-tactical actions per minute, i.e. conquered balls (CB), received balls (RB), lost balls (LB), attacking balls/passes (AB), shots (S), rebounds (R), and the RPE were collected for each player for each SSG session. The results revealed that most of the differences between age groups were considered trivial/small and/or unclear for all SSG formats, though likely moderate differences between age groups were found in 1 x 1 and 2 x 2 SSGs, revealing that young players had greater frequencies of received, conquered, and lost balls. Within-age-group comparisons also showed moderate-to-large increases in technical actions during smaller formats than during larger ones. The main evidence of this study revealed that age group seemed not to largely influence the RPE or technical actions during different SSGs. However, smaller formats moderately-to-largely increased the number of technical actions. Interestingly, the biggest format (5 x 5) largely increased the RPE in comparison to the remaining formats. As a conclusion, technical actions and the RPE were influenced more by the format of play than by the age group.

Key words

  • basketball
  • SSG
  • drill-based games
  • youth
  • performance
  • technique
  • notational analysis
  • perceived exertion
Open Access

The Effects of Circuit Strength Training on the Development of Physical Fitness and Performance-Related Variables in Handball Players

Published Online: 31 Jan 2020
Page range: 191 - 203

Abstract

Abstract

The purpose of this study was to determine the effects of 12 weeks of circuit training on physical fitness in handball players. Subjects were randomly divided into a circuit strength training group (CT, n = 10) and a control group (CG, n = 9). Training sessions and matches were performed together, but during the 12-week intervention, the experimental group replaced part of the regular regimen with circuit strength training. Measures assessed in both groups before and after the intervention included: the agility T-half Test, the Yo-Yo intermittent recovery test, squat and counter-movement jumps, 15 m and 30 m sprints, and strength tests for the bench press, pull over, and the half squat. The upper limb bench press and pull-over tests along with the lower limb back half squat were performed using a 1-repetition maximum protocol. Based on the intraclass correlation coefficient and excluding the agility T-test (ICC = 0.72), we found excellent relative reliability for all variables (intraclass correlation coefficient range: 0.85-0.96, SEM range: 0.03-3.00). For absolute reliability or coefficients of variation, 71% (5/7) of the variables were excellent (CV < 5%). The circuit strength training group showed significant interaction effects and relevant effect sizes for the 12-week training period (8/9, 89%), and the mean effect size for the CT was markedly higher (d = 1.3, range: 0.41 - 2.76) than in the CG (d = - 1.0, range: -0.73 - 0.29). The largest improvements were in the Yo-Yo test (d = 2.76) and the squat jump (d = 2.05). These results show that a 12-week circuit strength training program is an effective method to increase handball-related performance characteristics.

Key words

  • conditioning program
  • circuit training
  • handball
  • vertical jump
  • physical fitness
Open Access

Analysis of Goal Scoring Patterns in the 2018 FIFA World Cup

Published Online: 31 Jan 2020
Page range: 205 - 210

Abstract

Abstract

The aim of this study was to analyse the goal scoring patterns during the 2018 FIFA World Cup. All goals scored during the tournament were analysed using the InStat video analysis system. The results showed that 169 goals (open play: 60.9%; set play: 39.1%) were scored during the competition. While 85 goals (82.5%) were scored from elaborate attacks, 18 goals (17.5%) came from counter attacks. A chi-square test indicated that there was a significant difference in the type of possession (χ2 (1, n = 103) = 43.58, p = 0.00). The highest number of goals was yielded from the final third (35%) as compared to the first (33%) and middle (32%) thirds. The results also indicated that most goals accounted from short passes (69.9%), while 13.6% of goals came from long passes and 16.5% from mixed passes (χ2 (2, n = 103) = 62.12, p = 0.00). Soccer coaches should incorporate set pieces in their training sessions in view to improve goal-scoring opportunities.

Key words

  • goals
  • set pieces
  • open play
  • tactics
  • performance
Open Access

Spanish Elite Soccer Reserve Team Configuration and the Impact of Physical Fitness Performance

Published Online: 31 Jan 2020
Page range: 211 - 218

Abstract

Abstract

The aim of this study was threefold: 1) to assess the configuration of an elite reserve soccer team, 2) to compare physical fitness performance of promoted and new players according to the playing position, and 3) to analyze the level of competitive participation attained by these players. We considered physical fitness tests (5 m and 15 m sprint, countermovement jump [CMJ] and aerobic endurance) performed by 192 players (age = 20.2 ± 2.3 years) enrolled in the reserve team of a Spanish La Liga club from 1994 to 2013. The players were classified according to the previous club criterion (promoted from the soccer academy and new players signed from other clubs), b) their playing position, and c) the competitive level attained until the 2016/2017 season (Spanish 1st and 2nd Divisions and the remaining competition levels). The proportion of promoted and new players was similar (p = 0.47). Overall, no substantial differences (unclear-small) were found in physical fitness performance between promoted and new players. Considering the playing position, promoted lateral defenders (LDs) showed better sprinting (ES = moderate) and CMJ (ES = moderate) performance than new LDs. In addition, promoted central midfielders (CMs) demonstrated better performance in the 5 m sprint and the CMJ (ES = moderate) than new CMs. The percentage of players who later competed in the Spanish 1st and 2nd Divisions was greater in promoted players compared to new players (p = 0.006). Physical fitness performance did not determine the selection of new players in a soccer elite reserve team. We may conclude that soccer academies should prioritize the selection and the training process of youth soccer players.

Key words

  • soccer
  • talent identification
  • neuromuscular performance
  • aerobic endurance
Open Access

The Effect of Neurofeedback Training on the Visual Processing Efficiency in Judo Athletes

Published Online: 31 Jan 2020
Page range: 219 - 227

Abstract

Abstract

This study aimed to analyse the effect of neurofeedback (NFB) training based on beta-wave amplification and theta-wave inhibition on the visual processing efficiency of judo athletes. The study examined 12 male athletes from the national team of the Polish Judo Association. Participants were divided into the experimental (EG, n = 6) and the control group (CG, n = 6). The NFB training protocol was performed and recorded using a Deymed Truscan system with 24 active channels. The effect of NFB training was examined by computer-based simple and complex reaction tests and selected tests of the Vienna Test System (VST). One – way ANOVA showed statistically significant differences between the CG and the EG in theta and beta values after the first and the second cycle of training. There were statistically significant differences between the CG and the EG in the results of reaction speed tests after individual cycles of training. The highest reduction in simple reaction time was obtained after the second training cycle, when training was performed every second day and lasted four minutes.

Key words

  • EEG
  • biofeedback
  • judo athletes
  • concentration
  • reaction time
  • visual processing
Open Access

Taekwondo Anaerobic Intermittent Kick Test: Discriminant Validity and an Update with the Gold-Standard Wingate Test

Published Online: 31 Jan 2020
Page range: 229 - 242

Abstract

Abstract

The aim of this study was to update the validity of the Taekwondo Anaerobic Intermittent Kick Test compared with the 30-s Wingate anaerobic test as the "Gold-Standard", squat jump and countermovement jump tests. The second objective was to examine whether this new specific test would be able to effectively discriminate between elite taekwondo athletes of different competitive levels. Twenty taekwondo athletes (15 males and 5 females) participated in the validation component, whereas 18 (14 males and 4 females) and 16 (13 males and 3 females) athletes participated in the reliability analysis of the Wingate anaerobic test and jumping tests, respectively. They performed these tests on two separate occasions (i.e., test-retest), in addition to the Taekwondo Anaerobic Intermittent Kick Test. To establish test’s discriminatory capability (i.e., construct validity), two subgroups were identified based on their international and national taekwondo performance: 10 elite (8 males and 2 females) and 9 sub-elite (7 males and 2 females) athletes. Wingate anaerobic test and jumping tests performances showed excellent reliability (ICC > 0.90, SEM < 5% for most variables). Significant correlations between Taekwondo Anaerobic Intermittent Kick Test, Wingate anaerobic test, and jumping tests’ variables were mostly "large". Elite taekwondo athletes showed greater taekwondo test performances compared with their sub-elite counterparts (p < 0.001). Receiving operating characteristic analysis indicated that the taekwondo specific test was able to effectively discriminate between elite and sub-elite taekwondo athletes. Overall, the findings of the current study support the concurrent validity of the Taekwondo Anaerobic Intermittent Kick Test. In particular, the Taekwondo Anaerobic Intermittent Kick Test showed good ability to effectively discriminate between taekwondo athletes of different competitive levels.

Key words

  • muscle power
  • sport-specific performance
  • anaerobic power
  • sensitivity
  • reliability
  • striking combat sports
Open Access

The Use of Small-Sided Games as an Aerobic Fitness Assessment Supplement within Elite Level Professional Soccer

Published Online: 31 Jan 2020
Page range: 243 - 253

Abstract

Abstract

The purpose of this investigation was to quantify the association between 5 vs. 5 small sided games (SSG) running performance and physiological performance during the Yo-YoIR1 test to ascertain the utility of SSGs as a potential fitness test modality within elite professional soccer players. Twenty-three (n = 23) elite male professional soccer players (mean ± SD age 25.3 ± 3.1 yrs, mass: 76 ± 9 kg, height: 176 ± 9 cm) were assessed. Players completed an intermittent aerobic fitness test (Yo-YoIR1) and a 5 vs. 5 SSGs protocol for the purpose of the study. During all SSGs players wore GPS (Statsports 10-Hz, Viper Pod, Newry, Northern Ireland) and HR monitors (Polar, Oy Kemple, Finland) with these measures related to Yo-YoIR1 running performance. Results revealed SSGs running performance (TD; m) and physiological performance (HR) showed the lowest CV% (< 5%), with high speed movements, accelerations and decelerations highlighting higher CV% during SSGs. Possibly small to possibly very large associations were observed for running performance during 5 vs. 5 SSGs and Yo-YoIR1 performance, with negative associations observed between physiological performance during SSG and YoYoIR1 running performance. To conclude, the current study observed how running performance during a standardised 5 vs. 5 SSG protocol within elite soccer cohorts is associated with the Yo-YoIR1 running performance. Given the low CV%, repeatability and large association of global running performance and internal load measures during a 5 vs. 5 SSG with Yo-YoIR1 performance, this particular soccer specific SSG protocol potentially supplements traditional non-sport specific testing assessments.

Key words

  • soccer
  • training
  • testing
  • fitness
  • assessment
  • GPS
Open Access

A Meta-Analysis on the Effect of Complex Training on Vertical Jump Performance

Published Online: 31 Jan 2020
Page range: 255 - 265

Abstract

Abstract

Complex training (CT) is a strength training intervention performed by completing all the sets of a resistance exercise followed by a series of high-velocity/plyometric exercise/s. The purpose of this novel study was to conduct a meta-analysis on the effect of CT on vertical jump (VJ) performance. Five electronic databases were searched using terms related to CT and the VJ. Studies needed to include randomized trials comparing CT with traditional resistance training (RT)/plyometric training (PLYO)/control (CON) lasting ≥ 4 weeks and the VJ as a dependent variable. Seven studies qualified for the meta-analysis with two studies differentiating VJ performance from CT and RT, two studies comparing VJ performance of CT and PLYO, and two studies establishing the difference in VJ performance between CT and CON. Results indicated similar improvement in VJ performance from CT and RT (p = 0.88). On the other hand, greater VJ performance in CT than PLYO was identified (ES = 0.86; 95% CI 0.24, 1.47; p = 0.01). CT also showed significantly greater enhancement in VJ compared to CON (ES = 1.14; 95% CI 0.60, 1.68; p < 0.01). In conclusion, CT can serve as alternative training from RT in improving VJ performance. On the other hand, CT is a better option in VJ enhancement than PLYO and CON.

Key words

  • vertical jump
  • countermovement jump
  • strength training
  • plyometrics
Open Access

Notational Comparison Analysis of Outdoor Badminton Men’s Single and Double Matches

Published Online: 31 Jan 2020
Page range: 267 - 273

Abstract

Abstract

The objectives of this study were to determine the results of the analysis of single and double outdoor badminton men’s matches and to determine the relationship between technical and tactical aspects in a study organized by the BWF (Badminton Word Federation), on a sand surface. Twenty men’s singles matches were recorded using video cameras and analysed with a Dartfish video analysis software package. Along with this, percentages of use of technical elements were analysed by comparing the different modalities. For the single format Lob, Clear, Drop, Smash, Drive were used, different from the double format that used Lob, Clear, Drop, Smash, Drive. The study confirmed the applicability of computerized notation analysis to determine the characteristics of Outdoor Badminton on sand.

Key words

  • outdoor badminton
  • notational analysis
  • technique
  • competition
Open Access

The Basketball Pass: A Systematic Review

Published Online: 31 Jan 2020
Page range: 275 - 284

Abstract

Abstract

The aim of this study was to review and organise current literature about the basketball pass and find the main factors that influence its learning skills and performance. Thirty-seven studies were included after the screening process. The documents were classified into main research topics. This review identified the following conclusions: (i) the assessment of passing performance should be made under uncertain and variable conditions to obtain information on players’ responses to competitive scenarios, (ii) it is advisable to incorporate new and random activities to facilitate the transference of learning to the competition, (iii) it is recommended to include overwhelming factors during the practice to minimise the effect of pressure and choking, (iv) optimal physical conditioning is essential to maintain passing performance during a basketball game, (v) small sided games and changing environments stand as the best training situations to improve passing skills. Furthermore, limited information is available about biomechanical aspects and physical conditioning training programs to improve passing skills in basketball. Likewise, there is sparse data on passing skills development in children.

Key words

  • team sports
  • technique
  • tactics
  • learning
  • skills
Open Access

Development of the Compulsive Exercising Scale for Extreme Sports Participants

Published Online: 31 Jan 2020
Page range: 285 - 298

Abstract

Abstract

The purpose of this study was to develop a scale to measure extreme sports participants’ levels of compulsive exercising. There are a number of compulsive exercising scales; however, none of them is targeted for extreme sports participants, whose emotional responses differ from those of non-extreme sports participants. Five hundred extreme sports participants were involved in this study, which included literature analysis, expert review, and exploratory and confirmatory factor analysis. Firstly, 95 items were selected from previous studies related to extreme sports and compulsive exercising. Secondly, nine experts scrutinized the content validity of the 95 items, and 82 items were found to be valid. Thirdly, the 82-item survey was initially administered to 253 participants for the purposes of exploratory factor analysis. Lastly, the 20-item survey that came out as a result of the 82 items being put through the exploratory factor analysis was distributed to the other 247 participants in the confirmatory factor analysis. In the final results, 16 items regarding the four factors of the “withdrawal symptom”, “attachment”, “struggle”, and “obsession” were confirmed. The factors used to measure extreme sports participants’ compulsiveness in this study reflect somewhat different dimensions from those developed in previous studies for non-extreme sports participants or exercisers. Only factors in the affective and behavioral dimensions are included in the present study’s scale, while factors in the cognitive or the combined cognitive, affective, and behavioral dimensions were investigated in previous studies. This explains the need for the present study.

Key words

  • compulsive exercising scale
  • extreme sports
  • factor analysis
Open Access

The Relationship Between Tactical Positioning and the Race Outcome in 800-M Running at the 2016 Olympic Games and 2017 IAAF World Championship

Published Online: 31 Jan 2020
Page range: 299 - 305

Abstract

Abstract

The purpose of this analysis was to quantify the probability of achieving a top-3 finishing position during 800-m races at a global championship, based on dispersion of the runners during the first and second laps and the difference in split times between laps. Overall race times, intermediate and finishing positions and 400 m split times were obtained for 43 races over 800 m (21 men’s and 22 women’s) comprising 334 individual performances, 128 of which resulted in higher positions (top-3) and 206 the remaining positions. Intermediate and final positions along with times, the dispersion of the runners during the intermediate and final splits (SS1 and SS2), as well as differences between the two split times (Dsplits) were calculated. A logistic regression model was created to determine the influence of these factors in achieving a top-3 position. The final position was most strongly associated with SS2, but also with SS1 and Dsplits. The Global Significance Test showed that the model was significant (p < 0.001) with a predictive ability of 91.08% and an area under the curve coefficient of 0.9598. The values of sensitivity and specificity were 96.8% and 82.5%, respectively. The model demonstrated that SS1, SS2 and Dplits explained the finishing position in the 800-m event in global championships.

Key words

  • behavior
  • performance
  • endurance
  • athletics
26 Articles

Short Communication

Open Access

Understanding Player Load: Meanings and Limitations

Published Online: 31 Jan 2020
Page range: 5 - 9

Abstract

Abstract

We present a critical reflection on the mechanical variable Player Load, which is based on acceleration data and commonly used in sports. Our motivation to write this paper came from the difficulties that we encountered in the calculation and interpretation of Player Load using our own data, since we did not use the Catapult Sports equipment, which is a merchandise of the company that proposed this variable. We reviewed existing literature in order to understand Player Load better; we found many inconsistencies in PL calculation methods and in the meanings attached to it. Accordingly, this paper presents a brief discussion on the meanings that have been assigned to Player Load, its limitations, and the lack of clear and complete information about Player Load calculation methods. Moreover, the use of arbitrary units and different practical meanings in the literature has associated Player Load with many physical quantities, thereby resulting in difficulties in determining what Player Load measures within the context of sports. It seems that Player Load is related to the magnitude of changes in acceleration, but not the magnitude of acceleration itself. Therefore, coaches and sports scientists should take this information into account when they use Player Load to prescribe and monitor external loads. We concluded that a deeper discussion of Player Load as a descriptor of external load is warranted in the sports sciences literature.

Key words

  • acceleration
  • external training load
  • mechanical variables

Section I - Kinesiology

Open Access

The Effectiveness of a Dry-Land Shoulder Rotators Strength Training Program in Injury Prevention in Competitive Swimmers

Published Online: 31 Jan 2020
Page range: 11 - 20

Abstract

Abstract

Competitive swimmers usually undergo large mileage of daily training, in which propulsive force is produced mainly by the upper limbs. Some studies claim that dry-land shoulder rotators injury prevention programs before the in-water swim practice are paramount. However, the effect of shoulder strengthening prior to water training is unclear. This study aimed to analyse the acute effects of training programs conducted on dry land with the goal of preventing shoulder rotators injuries. A group of young swimmers (N = 23) was recruited to participate in this research. The peak torques of shoulder internal and external rotators were assessed before and after the completion of the compensatory strength training program. The isokinetic assessment was performed using two different protocols: 3 repetitions at 60/s and 20 repetitions at 180/s. Except for a trivial reduction in strength after the training program, there were no other significant differences in any of the studied variables (shoulders rotators endurance, strength and muscle balance). All results showed trivial to small effect sizes. Our findings suggest that a compensatory strength training program does not have a significant acute effect on the strength, endurance and muscle balance of shoulder rotators in young swimmers.

Key words

  • swimming
  • isokinetic strength
  • shoulder rotators
  • acute effects
Open Access

Development and Validation of a Checklist to Assess Proficient Performance of Basketball Straight Speed Dribbling Skill

Published Online: 31 Jan 2020
Page range: 21 - 31

Abstract

Abstract

The aim of this study was to develop and validate a checklist to assess proficient performance of basketball straight speed dribbling skill. The sample was composed of 100 children and adolescents between 7 and 15 years of age with and without structured practice in basketball. The validation process tested the validity domain, decision, tendencies, reliability, responsiveness, and objectivity. The results show that the checklist contains criteria that represent the speed dribbling skill and is sensible to distinguish between different proficiency levels of performance. The results also expressed high reliability and objectivity (intra and inter-rater). In light of the findings, we concluded that the checklist can be used to reliably analyze performance and evaluate the process of learning and development of the straight speed dribbling skill.

Key words

  • sport skills
  • measurement
  • motor performance
  • team sport games
Open Access

Intra-Trial Reliability and Usefulness of Isometric Mid-Thigh Pull Testing on Portable Force Plates

Published Online: 31 Jan 2020
Page range: 33 - 45

Abstract

Abstract

The aim of this study was to assess the intra-trial reliability and usefulness of portable force plates and a customised Isometric Mid-Thigh Pull rig. Twenty males (age: 24.1 ± 2.5 years, body height: 177.7 ± 0.09 cm, body mass: 88.4 ± 17.9 kg) with weightlifting experience ± 12 months attended 1 familiarisation session and 1 testing session where 4 isometric mid-thigh pulls were performed. Maximum force, absolute peak force (PF), relative PF, allometrically scaled PF, and force (150, 200, 250 ms) were deemed reliable (ICC ≥ 0.91 and CV ≤ 9.8%) based on predetermined criteria (ICC ≥ 0.8 and CV ≤ 10%). The impulse and the rate of force development (RFD) were deemed unreliable (ICC ≤ 0.91 and CV ≥ 10 %) at all time points. Maximum force, absolute PF, relative PF to body weight and body mass, rand allometrically scaled PF, had a typical error (TE) lower than the smallest worthwhile change small effect (SWC0.2) and moderate effect (SWC0.5) and were rated as good with regard to usefulness. The TE for force at selected time points (150, 200, 250 ms) was also higher than the SWC0.2, achieving a rating of marginal, but TE was higher than SWC0.5, achieving a rating of good with regard to usefulness. Portable force plates and customised rigs can reliably determine peak force and force output at different time points and for detecting the SWC in maximum and absolute force measures, greater familiarisation may be required to establish reliability of other variables such as the impulse and the RFD.

Key words

  • isometric strength
  • force time curve
  • mid-thigh pull
  • performance testing
Open Access

Jumping-based Asymmetries are Negatively Associated with Jump, Change of Direction, and Repeated Sprint Performance, but not Linear Speed, in Adolescent Handball Athletes

Published Online: 31 Jan 2020
Page range: 47 - 58

Abstract

Abstract

The aim of the present study was to determine the association of multi-directional jumping asymmetries with measures of physical performance. Forty-two youth handball athletes (age: 16.0 ± 1.3 years; body height: 174.11 ± 7.3 cm; body mass: 70.49 ± 13.3 kg) performed a mid-season fitness test battery consisting of single leg countermovement, lateral and broad jump tests, two change of direction speed (CODS) tests, an 8 x 10 m repeated sprint test, and a 20 m sprint. The Kappa coefficient showed only ‘slight’ levels of agreement (K range = -0.05 to 0.15), indicating that asymmetries rarely favoured the same side during each of the jump tests. The single leg countermovement jump showed significantly (p = 0.006) larger asymmetries (11.2 ± 8.4) than the broad jump (6.4 ± 4.6) and significant correlations were present between jumping asymmetries and jump (r = -0.32 to -0.52), CODS (r = 0.31 to 0.32) and repeated sprint (r = 0.35 to 0.40) performance. The findings of the present study highlight the independent nature of jumping asymmetries and associations with measures of physical performance. Practitioners are encouraged to use multiple tests to detect existing side differences and consider appropriate training interventions for the reduction of inter-limb asymmetries.

Key words

  • handball
  • inter-limb differences
  • performance reduction
  • youth athletes
Open Access

The Effects of Compression Garments on Stability and Lower Limb Kinematics During a Forward Lunge

Published Online: 31 Jan 2020
Page range: 59 - 68

Abstract

Abstract

Compression garments have been used to minimise injury risk, through improvements in stability and joint positioning; yet, it is unclear whether there is an optimal length or tightness of these garments that may maximise observed benefits. This study measured the effect of three different garment types, at two different tightness levels, on lower extremity stability and alignment during a forward lunge movement. Sixteen healthy adults (7 female, 9 male; 24.3 ± 2.9 years) were recruited as participants. Stability of the lead foot, as well as lower body joint kinematics, were recorded using an Oqus 12-camera system, surrounding participants as they executed three forward lunges onto a Matscan pressure mat under seven compression conditions (Control, Light/Heavy Calf, Light/Heavy Socks, Light/Heavy Leggings). Mean minimum time-to-boundary (mmTtB) (derived from centre of pressure measures) and frontal plane kinematics (lateral pelvic tilt, knee valgus, ankle inversion/eversion) were used to assess the effect of garment tightness and length on lunge stability and joint alignment, respectively. A significant effect of tightness on mmTtB was observed (F(1,105) = 8.192; p = .005, η2 = .072), with Heavy garments eliciting longer mmTtB compared to their corresponding Light (-.18 ± .06 s; p = .015) or Control (-.28 ± .09 s; p = .007) conditions. No significant effects of garment tightness or length on lower body kinematics were evident. The results of this study suggest stability during a forward lunge is improved through the use of tight-fitted compression garments.

Key words

  • time-to-boundary
  • proprioception
  • injury
  • joint alignment
Open Access

Lower Extremity Stiffness in Collegiate Distance Runners Pre- and Post-Competition

Published Online: 31 Jan 2020
Page range: 69 - 77

Abstract

Abstract

Previous evidence has suggested that there is a relationship between leg stiffness and improved running performance. The purpose of this investigation was to determine how leg stiffness of runners was influenced in the 24 and 48 hour period following a cross country race. Twenty-two collegiate cross-country runners (13 males, 9 females, 19.5 ± 1.4 yr) were recruited and participated in the study. Leg stiffness was assessed 24 hours before and after a race as well as 48 hours post-race. Three jumping protocols were conducted: 1) a static jump, 2) a countermovement jump, and 3) a vertical hopping test. Two embedded force plates (1000 Hz) were utilized to measure ground reaction forces for each test and a metronome was utilized to maintain hopping frequency (2.2 Hz). A significant main effect was found for a static jump, a countermovement jump and leg stiffness. Leg stiffness was significantly reduced 24 hours post-race (pre-race 36.84 kN·m-1, 24h post 33.11 kN·m-1, p < 0.05), but not 48 hours post-race (36.30 kN·m-1). No significant differences were found in post-hoc analysis for the squat jump, countermovement jump height and the eccentric utilization ratio. Following a cross-country race, leg stiffness significantly declined in a group of collegiate runners in the immediate 24 hours post-race, but returned to baseline 48 hours post-race. Sport scientists and running coaches may be able to monitor leg stiffness as a metric to properly prescribe training regiments.

Key words

  • hopping
  • fatigue
  • running performance
  • neuromuscular characteristics
  • stretch-shortening cycle (SSC)

Section II - Exercise Physiology & Sports Medicine

Open Access

Nutritional Recommendations for Physique Athletes

Published Online: 31 Jan 2020
Page range: 79 - 108

Abstract

Abstract

The popularity of physique sports is increasing, yet there are currently few comprehensive nutritional guidelines for these athletes. Physique sport now encompasses more than just a short phase before competition and offseason guidelines have recently been published. Therefore, the goal of this review is to provide an extensive guide for male and female physique athletes in the contest preparation and recovery period. As optimal protein intake is largely related to one’s skeletal muscle mass, current evidence supports a range of 1.8-2.7 g/kg. Furthermore, as a benefit from having adequate carbohydrate to fuel performance and activity, low-end fat intake during contest preparation of 10-25% of calories allows for what calories remain in the “energy budget” to come from carbohydrate to mitigate the negative impact of energy restriction and weight loss on training performance. For nutrient timing, we recommend consuming four or five protein boluses per day with one consumed near training and one prior to sleep. During competition periods, slower rates of weight loss (≤0.5% of body mass per week) are preferable for attenuating the loss of fat-free mass with the use of intermittent energy restriction strategies, such as diet breaks and refeeds, being possibly beneficial. Additionally, physiological and psychological factors are covered, and potential best-practice guidelines are provided for disordered eating and body image concerns since physique athletes present with higher incidences of these issues, which may be potentially exacerbated by certain traditional physique practices. We also review common peaking practices, and the critical transition to the post-competition period.

Key words

  • physique
  • bodybuilding
  • nutrition
  • contest preparation
  • competition recovery
Open Access

Comparison of Morphological Profiles and Performance Variables Between Female Volleyball Players of the First and Second Division In Portugal

Published Online: 31 Jan 2020
Page range: 109 - 117

Abstract

Abstract

Knowledge of players’ anthropometric profiles may contribute to a better understanding of the differences between their performance levels. For example, vertical jump height, which is a major indicator of a volleyball player’s performance, is influenced by favorable anthropometric variables. This study’s aim was to describe anthropometric profiles of elite female volleyball players competing in the 1st and 2nd divisions in Portugal and to link these profiles with performance skills such as jump height obtained during blocking and spiking actions. Fifty-nine volleyball players were analyzed according to their competitive level, forming three independent groups: GA (n = 20, A1 division, ranked first), GB (n = 21, A1 division, ranked last) and GC (n = 18, A2 division). Anthropometric data collected included body mass and height, arm span, seven skinfolds (triceps, biceps, subscapular, suprailiac, abdominal, thigh and calf), four body perimeters (relaxed brachial, contracted brachial, thigh and calf), and two body diameters (humeral and femoral). Performance data included the height obtained during block and spike actions. Significant differences were found between groups (GA/GB from A1 and GC from A2). Players in the GA had the highest body mass (68.05 ± 6.62 kg, p < 0.05), body height (176.35 ± 6.21 cm, p < 0.05), arm span (177.59 ± 6.09 cm, p < 0.05), lean mass (53.51 ± 4.94 kg, p < 0.05) and vertical jump heights (block: 0.36 ± 0.06 m and spike: 0.43 ± 0.05 m, p < 0.05). As expected, the fat mass percentage of GA players was the lowest (21.30 ± 2.61%). The results suggest that anthropometric profiles of volleyball players may vary according to the competitive level. The higher body mass, body height, arm span, and lean mass presented by GA players in comparison with GC players suggest these variables are important for top-level performance, since these athletes also exhibited higher jump heights. Variables such as height and arm span have a considerable genetic influence and could be important for early talent identification in volleyball. Other variables such as body mass, lean mass and vertical jump performance are more complex, since they also reflect the effects of environmental and training conditions.

Key words

  • anthropometric characteristics
  • volleyball
  • somatotype
  • vertical jump
Open Access

Roller Massage: Comparing the Immediate Post‐Treatment Effects Between an Instructional Video and a Self‐Preferred Program Using Two Different Density‐Type Roller Balls

Published Online: 31 Jan 2020
Page range: 119 - 129

Abstract

Abstract

The aims of this study were to (1) compare the immediate post-treatment effects of an instructional video versus a self-preferred program on the hip range of motion and a pressure pain threshold using two different density roller balls, and (2) compare the effects of the two roller balls on those variables. Forty adults were randomly allocated into four groups: (1) MB1-video, (2) MB1-self-preferred, (3) MBX-video, and (4) MBX-self-preferred. Participants followed a video or a self-preferred program using either a moderate (MB1) or a hard (MBX) density ball. Main outcomes were passive hip internal rotation, external rotation, and a pressure pain threshold. For MB1, the video produced greater outcomes than the self-program for external rotation (10◦ versus 2◦), internal rotation (7◦ versus 2◦), and the pain threshold (210 kPa versus 44 kPa). For MBX, the video produced greater outcomes than the self-program for external rotation (8◦ versus 1◦), internal rotation (5◦ versus 1◦), and the pain threshold (184 kPa versus 30 kPa). When comparing roller balls, the MB1 produced greater outcomes than the MBX for external rotation (10◦ versus 8◦), internal rotation (7◦ versus 5◦), and the pain threshold (210 kPa versus 184 kPa) with the video. For the self-preferred program, the MB1 produced greater outcomes for external rotation (2◦ versus 1◦), internal rotation (2◦ versus 1◦), and the pain threshold (44 kPa versus 30 kPa). The instructional video and a moderate density ball produced greater immediate post-treatment outcomes than the self-program and a hard density ball. Professionals should consider using the video to teach technique and match clients to a specific density-type roller ball.

Key words

  • foam
  • massage
  • myofascial
  • pain
  • release
Open Access

Muscle Thickness During Core Stability Exercises in Children and Adults

Published Online: 31 Jan 2020
Page range: 131 - 144

Abstract

Abstract

Core stability exercises are regular part of exercise programs for asymptomatic individuals across ages. The purpose of this study was to examine deep abdominal and multifidus muscle thickness in children and adults and to determine reliability of the rehabilitative ultrasound (RUSI) imaging. Transversus abdominis and lumbar multifidus thickness at rest and during core stability exercise were examined in pre-pubertal children (N = 23), adolescents (N = 20), young adults (N = 21) and middle-aged adults (N = 22). Thirty-nine participants were re-tested one week after to establish reliability. Muscle thickness at rest was lower in children and adolescents compared with young and middle-aged adults (p < 0.008). Young adults displayed the highest relative transversus abdominis thickness upon contraction (p < 0.008). Lumbar multfidus contraction thickness was greater in young-adults than middle-aged adults and pre-pubertal children (p < 0.008), but it was similar between young-adults and adolescents (p > 0.008). Reliability was high for both muscles (ICC3,3 = 0.76 - 0.99). The age-related differences in muscle thickness indicate that core stability exercises may be beneficial for children and middle-aged adults.

Key words

  • childhood
  • musculoskeletal ultrasound
  • repeatability
  • core exercise
  • core stability
Open Access

Eating Habits and Body Composition of International Elite Soccer Referees

Published Online: 31 Jan 2020
Page range: 145 - 153

Abstract

Abstract

Soccer referees are a specific group of the athletes’ population whose careers peak from 30 to 45 years old. An athlete's performance is not only determined by physical training but also by a lifestyle, e.g. eating habits. The purpose of this study was to verify current eating habits and resulting body composition of a group of elite international soccer referees. At an international FIFA seminar 60 elite international soccer referees (aged 39.2 ± 4.2 years) were enrolled. A body composition assessment was performed with skinfold thickness and bio impedance analysis, while eating habits were evaluated with a multi-pass 24-hour dietary recall. The body composition showed a normal weight condition with a fat content of 11.4 ± 2.5%. Macronutrients showed a low level of carbohydrates (43.6 ± 5.4%) and a high level of fat (40.0 ± 4.5%). Micronutrients showed a low level of calcium, potassium, zinc, magnesium, iodine, vitamin B12 and vitamin B9. Even though their body composition was within the normal range, the current eating habits of elite international soccer referees did not appear to follow the nutrition guidelines. Therefore, it would be advisable to provide knowledge on nutrition for this particular category of sports subjects, an individualized nutritional plan would be advisable, in order to achieve and maintain better performance and appropriate body composition for their role.

Key words

  • match officials
  • soccer
  • fat mass
  • micronutrients
  • macronutrients
Open Access

Hormonal Response to Incremental and Continuous Exercise in Cyclists with Left Ventricle Hypertrophy

Published Online: 31 Jan 2020
Page range: 155 - 166

Abstract

Abstract

The aim of this study was to assess the effects of incremental and continuous exercise on the concentration of insulin-like growth factor-1 (IGF-1), growth hormone (GH), testosterone (T), and cortisol (C), as well as to investigate whether increased cardiac dimensions in cyclists were related to changes in these hormones and cardiac biomarkers. The study included 30 elite cyclists divided into two groups, i.e., athletes with left ventricle hypertrophy (a LVH group), and a control group (CG) without LVH. The study protocol included performance of a standard incremental exercise (IncEx) test to measure athletes’ maximum power (Pmax), maximum oxygen uptake (VO2max), and lactate threshold (LAT). The IncEx test results were then used to determine the intensity of the continuous exercise (ConEx) test which was performed after the 1-week washout period. Cyclists with LVH and without LVH did not differ in resting hormone concentrations and cardiac biomarkers levels. There was a significant effect of exercise on serum IGF-1 levels (p < 0.05) in the LVH group and a combined effect of the type of exercise and LVH on IGF-1 (p < 0.05). Cyclists with LVH demonstrated higher post exercise T levels recorded in response to exercise compared to the CG (p < 0.01). Significantly higher serum T levels were observed in response to ConEx compared to IncEx in the LVH group and the CG (p < 0.05 and p < 0.05, respectively). In the LVH group, a significant positive correlation between the post-exercise T/C ratio and left ventricular mass index was observed (r = 0.98, p < 0.01). There were no effects of heart hypertrophy on cardiac standard biomarkers. Incremental and continuous exercise caused a marked increase in steroid hormone concentrations and moderate strengthening of insulin growth factors effects. Regular incremental exercise seems to induce beneficial cardiac adaptations via significant increases in the concentration of anabolic factors compared to the same training mode yet with constant exercise intensity.

Key words

  • hormones
  • cardiac markers
  • myocardium
  • cycling
  • endurance exercise

Section III - Sports Training

Open Access

Effect of an Inside Floater on Soccer Players Tactical Behaviour in Small Sided and Conditioned Games

Published Online: 31 Jan 2020
Page range: 167 - 177

Abstract

Abstract

The aim of this study was to verify the effect of an inside floater on soccer players’ tactical behaviour in small-sided and conditioned games (SSCGs). The sample comprised 54 Brazilian top-level academy players. The instrument used to assess players’ tactical behaviour was the System of Tactical Assessment in Soccer (FUT-SAT). Tactical behaviour was analysed through the number of tactical actions and the percentage of correct actions regarding the core tactical principles of soccer. Repeated measures test was used to compare tactical behaviour between games (SSCGs) with and without an inside floater. Pearson’s r was used to verify the effect size of the inside floater on tactical behaviour. As for tactical actions, SSCGs with an inside floater displayed significantly lower means for the tactical principles of penetration (2.76 ± 1.63; p < .001), delay (6.11 ± 2.68; p < .018), defensive coverage (1.64 ± 1.14; p < .001) and significantly higher means for the tactical principle of defensive unity (14.98 ± 4.57; p < .032). With respect to the percentage of correct actions, SSCGs with an inside floater displayed significantly lower means for all tactical principles, except for offensive coverage (90.5 ± 18.48; p < 1.000). It was concluded that the inside floater allowed players to modify their behaviour in such a way that they adapted to the constraints imposed by the presence of an inside floater. Furthermore, the inside floater provided more difficulty for players, and thus may be considered an important task constraint to be added in SSCGs.

Key words

  • soccer
  • task constraint
  • training
  • youth soccer players
  • core tactical principles
Open Access

Technical Performance and Perceived Exertion Variations Between Small-Sided Basketball Games in Under-14 and Under-16 Competitive Levels

Published Online: 31 Jan 2020
Page range: 179 - 189

Abstract

Abstract

The aim of this study was twofold: i) to compare the rate of perceived exertion (RPE) and the frequencies of technical actions per minute in different small-sided games (SSGs) between under-14 and under-16 age groups, and ii) to compare the RPE and the frequencies of technical actions per minute between 1 x 1, 2 x 2, 3 x 3, 4 x 4 and 5 x 5 formats within age groups. Twenty young male basketball players from the same club (N = 10, from under-14; N = 10, from under-16) competing at the national level voluntarily participated in this study. Five different SSGs (1 x 1, 2 x 2, 3 x 3, 4 x 4 and 5 x 5) were played twice on courts of the same relative area and were compared in terms of the RPE and technical actions. The number of technical-tactical actions per minute, i.e. conquered balls (CB), received balls (RB), lost balls (LB), attacking balls/passes (AB), shots (S), rebounds (R), and the RPE were collected for each player for each SSG session. The results revealed that most of the differences between age groups were considered trivial/small and/or unclear for all SSG formats, though likely moderate differences between age groups were found in 1 x 1 and 2 x 2 SSGs, revealing that young players had greater frequencies of received, conquered, and lost balls. Within-age-group comparisons also showed moderate-to-large increases in technical actions during smaller formats than during larger ones. The main evidence of this study revealed that age group seemed not to largely influence the RPE or technical actions during different SSGs. However, smaller formats moderately-to-largely increased the number of technical actions. Interestingly, the biggest format (5 x 5) largely increased the RPE in comparison to the remaining formats. As a conclusion, technical actions and the RPE were influenced more by the format of play than by the age group.

Key words

  • basketball
  • SSG
  • drill-based games
  • youth
  • performance
  • technique
  • notational analysis
  • perceived exertion
Open Access

The Effects of Circuit Strength Training on the Development of Physical Fitness and Performance-Related Variables in Handball Players

Published Online: 31 Jan 2020
Page range: 191 - 203

Abstract

Abstract

The purpose of this study was to determine the effects of 12 weeks of circuit training on physical fitness in handball players. Subjects were randomly divided into a circuit strength training group (CT, n = 10) and a control group (CG, n = 9). Training sessions and matches were performed together, but during the 12-week intervention, the experimental group replaced part of the regular regimen with circuit strength training. Measures assessed in both groups before and after the intervention included: the agility T-half Test, the Yo-Yo intermittent recovery test, squat and counter-movement jumps, 15 m and 30 m sprints, and strength tests for the bench press, pull over, and the half squat. The upper limb bench press and pull-over tests along with the lower limb back half squat were performed using a 1-repetition maximum protocol. Based on the intraclass correlation coefficient and excluding the agility T-test (ICC = 0.72), we found excellent relative reliability for all variables (intraclass correlation coefficient range: 0.85-0.96, SEM range: 0.03-3.00). For absolute reliability or coefficients of variation, 71% (5/7) of the variables were excellent (CV < 5%). The circuit strength training group showed significant interaction effects and relevant effect sizes for the 12-week training period (8/9, 89%), and the mean effect size for the CT was markedly higher (d = 1.3, range: 0.41 - 2.76) than in the CG (d = - 1.0, range: -0.73 - 0.29). The largest improvements were in the Yo-Yo test (d = 2.76) and the squat jump (d = 2.05). These results show that a 12-week circuit strength training program is an effective method to increase handball-related performance characteristics.

Key words

  • conditioning program
  • circuit training
  • handball
  • vertical jump
  • physical fitness
Open Access

Analysis of Goal Scoring Patterns in the 2018 FIFA World Cup

Published Online: 31 Jan 2020
Page range: 205 - 210

Abstract

Abstract

The aim of this study was to analyse the goal scoring patterns during the 2018 FIFA World Cup. All goals scored during the tournament were analysed using the InStat video analysis system. The results showed that 169 goals (open play: 60.9%; set play: 39.1%) were scored during the competition. While 85 goals (82.5%) were scored from elaborate attacks, 18 goals (17.5%) came from counter attacks. A chi-square test indicated that there was a significant difference in the type of possession (χ2 (1, n = 103) = 43.58, p = 0.00). The highest number of goals was yielded from the final third (35%) as compared to the first (33%) and middle (32%) thirds. The results also indicated that most goals accounted from short passes (69.9%), while 13.6% of goals came from long passes and 16.5% from mixed passes (χ2 (2, n = 103) = 62.12, p = 0.00). Soccer coaches should incorporate set pieces in their training sessions in view to improve goal-scoring opportunities.

Key words

  • goals
  • set pieces
  • open play
  • tactics
  • performance
Open Access

Spanish Elite Soccer Reserve Team Configuration and the Impact of Physical Fitness Performance

Published Online: 31 Jan 2020
Page range: 211 - 218

Abstract

Abstract

The aim of this study was threefold: 1) to assess the configuration of an elite reserve soccer team, 2) to compare physical fitness performance of promoted and new players according to the playing position, and 3) to analyze the level of competitive participation attained by these players. We considered physical fitness tests (5 m and 15 m sprint, countermovement jump [CMJ] and aerobic endurance) performed by 192 players (age = 20.2 ± 2.3 years) enrolled in the reserve team of a Spanish La Liga club from 1994 to 2013. The players were classified according to the previous club criterion (promoted from the soccer academy and new players signed from other clubs), b) their playing position, and c) the competitive level attained until the 2016/2017 season (Spanish 1st and 2nd Divisions and the remaining competition levels). The proportion of promoted and new players was similar (p = 0.47). Overall, no substantial differences (unclear-small) were found in physical fitness performance between promoted and new players. Considering the playing position, promoted lateral defenders (LDs) showed better sprinting (ES = moderate) and CMJ (ES = moderate) performance than new LDs. In addition, promoted central midfielders (CMs) demonstrated better performance in the 5 m sprint and the CMJ (ES = moderate) than new CMs. The percentage of players who later competed in the Spanish 1st and 2nd Divisions was greater in promoted players compared to new players (p = 0.006). Physical fitness performance did not determine the selection of new players in a soccer elite reserve team. We may conclude that soccer academies should prioritize the selection and the training process of youth soccer players.

Key words

  • soccer
  • talent identification
  • neuromuscular performance
  • aerobic endurance
Open Access

The Effect of Neurofeedback Training on the Visual Processing Efficiency in Judo Athletes

Published Online: 31 Jan 2020
Page range: 219 - 227

Abstract

Abstract

This study aimed to analyse the effect of neurofeedback (NFB) training based on beta-wave amplification and theta-wave inhibition on the visual processing efficiency of judo athletes. The study examined 12 male athletes from the national team of the Polish Judo Association. Participants were divided into the experimental (EG, n = 6) and the control group (CG, n = 6). The NFB training protocol was performed and recorded using a Deymed Truscan system with 24 active channels. The effect of NFB training was examined by computer-based simple and complex reaction tests and selected tests of the Vienna Test System (VST). One – way ANOVA showed statistically significant differences between the CG and the EG in theta and beta values after the first and the second cycle of training. There were statistically significant differences between the CG and the EG in the results of reaction speed tests after individual cycles of training. The highest reduction in simple reaction time was obtained after the second training cycle, when training was performed every second day and lasted four minutes.

Key words

  • EEG
  • biofeedback
  • judo athletes
  • concentration
  • reaction time
  • visual processing
Open Access

Taekwondo Anaerobic Intermittent Kick Test: Discriminant Validity and an Update with the Gold-Standard Wingate Test

Published Online: 31 Jan 2020
Page range: 229 - 242

Abstract

Abstract

The aim of this study was to update the validity of the Taekwondo Anaerobic Intermittent Kick Test compared with the 30-s Wingate anaerobic test as the "Gold-Standard", squat jump and countermovement jump tests. The second objective was to examine whether this new specific test would be able to effectively discriminate between elite taekwondo athletes of different competitive levels. Twenty taekwondo athletes (15 males and 5 females) participated in the validation component, whereas 18 (14 males and 4 females) and 16 (13 males and 3 females) athletes participated in the reliability analysis of the Wingate anaerobic test and jumping tests, respectively. They performed these tests on two separate occasions (i.e., test-retest), in addition to the Taekwondo Anaerobic Intermittent Kick Test. To establish test’s discriminatory capability (i.e., construct validity), two subgroups were identified based on their international and national taekwondo performance: 10 elite (8 males and 2 females) and 9 sub-elite (7 males and 2 females) athletes. Wingate anaerobic test and jumping tests performances showed excellent reliability (ICC > 0.90, SEM < 5% for most variables). Significant correlations between Taekwondo Anaerobic Intermittent Kick Test, Wingate anaerobic test, and jumping tests’ variables were mostly "large". Elite taekwondo athletes showed greater taekwondo test performances compared with their sub-elite counterparts (p < 0.001). Receiving operating characteristic analysis indicated that the taekwondo specific test was able to effectively discriminate between elite and sub-elite taekwondo athletes. Overall, the findings of the current study support the concurrent validity of the Taekwondo Anaerobic Intermittent Kick Test. In particular, the Taekwondo Anaerobic Intermittent Kick Test showed good ability to effectively discriminate between taekwondo athletes of different competitive levels.

Key words

  • muscle power
  • sport-specific performance
  • anaerobic power
  • sensitivity
  • reliability
  • striking combat sports
Open Access

The Use of Small-Sided Games as an Aerobic Fitness Assessment Supplement within Elite Level Professional Soccer

Published Online: 31 Jan 2020
Page range: 243 - 253

Abstract

Abstract

The purpose of this investigation was to quantify the association between 5 vs. 5 small sided games (SSG) running performance and physiological performance during the Yo-YoIR1 test to ascertain the utility of SSGs as a potential fitness test modality within elite professional soccer players. Twenty-three (n = 23) elite male professional soccer players (mean ± SD age 25.3 ± 3.1 yrs, mass: 76 ± 9 kg, height: 176 ± 9 cm) were assessed. Players completed an intermittent aerobic fitness test (Yo-YoIR1) and a 5 vs. 5 SSGs protocol for the purpose of the study. During all SSGs players wore GPS (Statsports 10-Hz, Viper Pod, Newry, Northern Ireland) and HR monitors (Polar, Oy Kemple, Finland) with these measures related to Yo-YoIR1 running performance. Results revealed SSGs running performance (TD; m) and physiological performance (HR) showed the lowest CV% (< 5%), with high speed movements, accelerations and decelerations highlighting higher CV% during SSGs. Possibly small to possibly very large associations were observed for running performance during 5 vs. 5 SSGs and Yo-YoIR1 performance, with negative associations observed between physiological performance during SSG and YoYoIR1 running performance. To conclude, the current study observed how running performance during a standardised 5 vs. 5 SSG protocol within elite soccer cohorts is associated with the Yo-YoIR1 running performance. Given the low CV%, repeatability and large association of global running performance and internal load measures during a 5 vs. 5 SSG with Yo-YoIR1 performance, this particular soccer specific SSG protocol potentially supplements traditional non-sport specific testing assessments.

Key words

  • soccer
  • training
  • testing
  • fitness
  • assessment
  • GPS
Open Access

A Meta-Analysis on the Effect of Complex Training on Vertical Jump Performance

Published Online: 31 Jan 2020
Page range: 255 - 265

Abstract

Abstract

Complex training (CT) is a strength training intervention performed by completing all the sets of a resistance exercise followed by a series of high-velocity/plyometric exercise/s. The purpose of this novel study was to conduct a meta-analysis on the effect of CT on vertical jump (VJ) performance. Five electronic databases were searched using terms related to CT and the VJ. Studies needed to include randomized trials comparing CT with traditional resistance training (RT)/plyometric training (PLYO)/control (CON) lasting ≥ 4 weeks and the VJ as a dependent variable. Seven studies qualified for the meta-analysis with two studies differentiating VJ performance from CT and RT, two studies comparing VJ performance of CT and PLYO, and two studies establishing the difference in VJ performance between CT and CON. Results indicated similar improvement in VJ performance from CT and RT (p = 0.88). On the other hand, greater VJ performance in CT than PLYO was identified (ES = 0.86; 95% CI 0.24, 1.47; p = 0.01). CT also showed significantly greater enhancement in VJ compared to CON (ES = 1.14; 95% CI 0.60, 1.68; p < 0.01). In conclusion, CT can serve as alternative training from RT in improving VJ performance. On the other hand, CT is a better option in VJ enhancement than PLYO and CON.

Key words

  • vertical jump
  • countermovement jump
  • strength training
  • plyometrics
Open Access

Notational Comparison Analysis of Outdoor Badminton Men’s Single and Double Matches

Published Online: 31 Jan 2020
Page range: 267 - 273

Abstract

Abstract

The objectives of this study were to determine the results of the analysis of single and double outdoor badminton men’s matches and to determine the relationship between technical and tactical aspects in a study organized by the BWF (Badminton Word Federation), on a sand surface. Twenty men’s singles matches were recorded using video cameras and analysed with a Dartfish video analysis software package. Along with this, percentages of use of technical elements were analysed by comparing the different modalities. For the single format Lob, Clear, Drop, Smash, Drive were used, different from the double format that used Lob, Clear, Drop, Smash, Drive. The study confirmed the applicability of computerized notation analysis to determine the characteristics of Outdoor Badminton on sand.

Key words

  • outdoor badminton
  • notational analysis
  • technique
  • competition
Open Access

The Basketball Pass: A Systematic Review

Published Online: 31 Jan 2020
Page range: 275 - 284

Abstract

Abstract

The aim of this study was to review and organise current literature about the basketball pass and find the main factors that influence its learning skills and performance. Thirty-seven studies were included after the screening process. The documents were classified into main research topics. This review identified the following conclusions: (i) the assessment of passing performance should be made under uncertain and variable conditions to obtain information on players’ responses to competitive scenarios, (ii) it is advisable to incorporate new and random activities to facilitate the transference of learning to the competition, (iii) it is recommended to include overwhelming factors during the practice to minimise the effect of pressure and choking, (iv) optimal physical conditioning is essential to maintain passing performance during a basketball game, (v) small sided games and changing environments stand as the best training situations to improve passing skills. Furthermore, limited information is available about biomechanical aspects and physical conditioning training programs to improve passing skills in basketball. Likewise, there is sparse data on passing skills development in children.

Key words

  • team sports
  • technique
  • tactics
  • learning
  • skills
Open Access

Development of the Compulsive Exercising Scale for Extreme Sports Participants

Published Online: 31 Jan 2020
Page range: 285 - 298

Abstract

Abstract

The purpose of this study was to develop a scale to measure extreme sports participants’ levels of compulsive exercising. There are a number of compulsive exercising scales; however, none of them is targeted for extreme sports participants, whose emotional responses differ from those of non-extreme sports participants. Five hundred extreme sports participants were involved in this study, which included literature analysis, expert review, and exploratory and confirmatory factor analysis. Firstly, 95 items were selected from previous studies related to extreme sports and compulsive exercising. Secondly, nine experts scrutinized the content validity of the 95 items, and 82 items were found to be valid. Thirdly, the 82-item survey was initially administered to 253 participants for the purposes of exploratory factor analysis. Lastly, the 20-item survey that came out as a result of the 82 items being put through the exploratory factor analysis was distributed to the other 247 participants in the confirmatory factor analysis. In the final results, 16 items regarding the four factors of the “withdrawal symptom”, “attachment”, “struggle”, and “obsession” were confirmed. The factors used to measure extreme sports participants’ compulsiveness in this study reflect somewhat different dimensions from those developed in previous studies for non-extreme sports participants or exercisers. Only factors in the affective and behavioral dimensions are included in the present study’s scale, while factors in the cognitive or the combined cognitive, affective, and behavioral dimensions were investigated in previous studies. This explains the need for the present study.

Key words

  • compulsive exercising scale
  • extreme sports
  • factor analysis
Open Access

The Relationship Between Tactical Positioning and the Race Outcome in 800-M Running at the 2016 Olympic Games and 2017 IAAF World Championship

Published Online: 31 Jan 2020
Page range: 299 - 305

Abstract

Abstract

The purpose of this analysis was to quantify the probability of achieving a top-3 finishing position during 800-m races at a global championship, based on dispersion of the runners during the first and second laps and the difference in split times between laps. Overall race times, intermediate and finishing positions and 400 m split times were obtained for 43 races over 800 m (21 men’s and 22 women’s) comprising 334 individual performances, 128 of which resulted in higher positions (top-3) and 206 the remaining positions. Intermediate and final positions along with times, the dispersion of the runners during the intermediate and final splits (SS1 and SS2), as well as differences between the two split times (Dsplits) were calculated. A logistic regression model was created to determine the influence of these factors in achieving a top-3 position. The final position was most strongly associated with SS2, but also with SS1 and Dsplits. The Global Significance Test showed that the model was significant (p < 0.001) with a predictive ability of 91.08% and an area under the curve coefficient of 0.9598. The values of sensitivity and specificity were 96.8% and 82.5%, respectively. The model demonstrated that SS1, SS2 and Dplits explained the finishing position in the 800-m event in global championships.

Key words

  • behavior
  • performance
  • endurance
  • athletics

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