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Journal Cover Sports
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  This is an Open Access Journal Open Access journal
   ISSN (Online) 2075-4663
   Published by MDPI Homepage  [151 journals]
  • Sports, Vol. 5, Pages 21: Sports Nutrition Knowledge, Perceptions,
           Resources, and Advice Given by Certified CrossFit Trainers

    • Authors: Cassie Maxwell, Kyle Ruth, Carol Friesen
      First page: 21
      Abstract: Background: CrossFit is a large, growing force in the fitness community. Currently, Level 1 and 2 CrossFit certification classes do not include nutrition education. The purpose of this study was to identify sports nutrition knowledge, perceptions, resources, and advice given by Certified CrossFit Trainers. Methods: An online questionnaire that measured these four constructs was placed on a private Facebook community, open only to certified CrossFit trainers, for 10 days. Results: Complete surveys were obtained from 289 CrossFit trainers. The mean Sport Nutrition Knowledge (SNK) score was 11.1 ± 2.1, equivalent to 65.3% ± 12.4% correct. The trainers perceived nutrition to be extremely important to athletic performance (9.4 ± 0.9 on a 10 point scale). Overall, the trainers graded their SNK higher than that of their CrossFit peers. The internet and CrossFit peers were the most frequently reported sources for nutrition information; Registered Dietitians were the least reported source. The Paleo and Zone diets were the most common dietary regimens recommended by CrossFit trainers. Results indicated a positive correlation between a CrossFit trainer’s self-reported hours of nutrition education and their SNK score (r = 0.17; p < 0.01). Conclusion: Nutrition education modules for Level 1 and 2 CrossFit trainers, developed with input from Board Certified Specialists in Sports Dietetics, are recommended.
      PubDate: 2017-03-24
      DOI: 10.3390/sports5020021
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 22: Self-Concept in Adolescents—Relationship
           between Sport Participation, Motor Performance and Personality Traits

    • Authors: Markus Klein, Michael Fröhlich, Eike Emrich
      First page: 22
      Abstract: The relationship between sport participation, personality development, self-concept and self-esteem has been discussed repeatedly. In this research, a standardized written survey together with tests on motor performance were carried out with 1399 students (707 male; 692 female) in school years 7 (12.9 ± 0.6 years) and 10 (15.8 ± 0.6 years) to measure the extent of a relationship between physical self-concept (self-developed short scale) and sporting activity, measured motor performance (German motor performance test DMT (Deutscher Motorik-Test) 6–18) and report mark in physical education. Relationships were also analyzed between physical self-concept and general personality traits (neuroticism, extraversion, openness to experiences, compatibility, and conscientiousness, measured with NEO Five Factor Inventory (NEO-FFI)). The assessment of own physical attractiveness and own athleticism differs by sex (F(1, 962) = 35.21; p < 0.001), whereby girls assess themselves more critically. Weak significant relationships are displayed between motor performance and the assessment of own physical attractiveness (r(395) = 0.31; p < 0.01). Motor performance is given a higher predictive value with regard to a subject’s own self-concept, (physical attractiveness β = 0.37; t(249) = 5.24; p < 0.001; athleticism β = 0.40; t(248) = 6.81; p < 0.001) than the mark achieved in physical education (physical attractiveness β = −0.01; n.s.; athleticism β = −0.30; t(248) = 5.10; p < 0.001). Relationships were found overall between personality traits and physical self-concept. The influence of the ‘neuroticism’ trait is particularly strong (physical attractiveness β = −0.44; t(947) = −13.58; p < 0.001; athleticism β = −0.27; t(948) = −7.84; p < 0.001). The more pronounced this trait, the lower the assessment of own physical attractiveness and own athleticism.
      PubDate: 2017-04-04
      DOI: 10.3390/sports5020022
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 23: Lack of Reality: Positive Self-Perceptions of
           Health in the Presence of Disease

    • Authors: Vincent Dalbo, Masaru Teramoto, Michael Roberts, Aaron Scanlan
      First page: 23
      Abstract: The aim of this study was to determine if adults in Central Queensland have accurate self-perceptions of health. Data were collected as part of the 2010 Central Queensland Social Survey (N = 1289). Overweight/obesity is considered a health disorder and was determined using body mass index. Disease states were determined by asking respondents if they have: heart disease, high/low blood pressure, high cholesterol, high triglycerides, thyroid disorder, diabetes, and osteopenia/osteoporosis. Self-perceptions of health were assessed by asking, “Would you say that in general your health is” poor, fair, good, very good, excellent, don’t know, and no response. An accurate health perception occurred if: (1) A respondent with a disease/health disorder reported that their health was poor/fair or (2) A respondent without a disease/health disorder reported that their health was good/very good/excellent. The proportions of people with an accurate health perception by disease/health disorder were compared using a χ2 test. A proportion ratio (PR) with a 95% confidence interval (CI) was calculated for each disease/health disorder. A logistic regression analysis was performed to examine the association between each disease/health disorder and health perception using gender, age, education, physical activity level, and smoking status as covariates. More than 50% of residents with each disease/health disorder reported their health to be good/very good/excellent. Residents with each disease/health disorder were less likely to have an accurate health perception than those without the corresponding disease/health disorder prior to (p < 0.001) and following adjustment of the covariates (p < 0.001). Our results suggest that overweight/obesity and prevalence of disease are not being recognized as unhealthy, which contradicts established definitions of health.
      PubDate: 2017-04-06
      DOI: 10.3390/sports5020023
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 24: Metabolic Power of Female Footballers in Various
           Small-Sided Games with Different Pitch Surfaces and Sizes

    • Authors: Jorge López-Fernández, Javier Sánchez-Sánchez, Leonor Gallardo, Jorge García-Unanue
      First page: 24
      Abstract: Small-sided-games (SSGs) seem to be a useful tool for replicating most types of scenarios found in sport competitions, but it is not that clear in female soccer. Game surface and pitch size seem to affect the intensity of SSGs, but no one has yet analysed the influence of these two variables together. The objective of this research was to analyse the metabolic power demands of various SSGs on possession play without goal-keepers, played on three different surfaces. Sixteen sub-elite female players performed three different four-a-side games (400 m2, 600 m2, and 800 m2) on three different surfaces (ground [GR]; natural grass [NG]; and artificial turf [AT]), recording a total of 96 events. Metabolic variables were recorded through a global positioning system (GPS). The GR condition obtained the lowest outputs for all variables in all of the SSGs. Furthermore, NG resulted in higher outcomes than AT for Average Metabolic Power (SSG 400 [+0.65; p = 0.019]; SSG 600 [+0.70; p = 0.04]); and equivalent distance (SSG 400 [+33.0; p = 0.02]; SSG 600 [+36.53; p = 0.04]). Moreover, SSG 400 obtained lower results than SSG 600 and SSG 800 for both AT and NG. In conclusion, playing on GR reduces the metabolic power of SSGs, While NG seems to be the most suitable surface for attaining highest metabolic responses for sub-elite female players. On the other hand, too big a pitch size may not increase the metabolic demands of the game.
      PubDate: 2017-04-17
      DOI: 10.3390/sports5020024
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 25: Effect of New Zealand Blackcurrant Extract on
           Repeated Cycling Time Trial Performance

    • Authors: Connor Murphy, Matthew Cook, Mark Willems
      First page: 25
      Abstract: New Zealand blackcurrant (NZBC) extract increased 16.1 km cycling time trial performance. The aim of the present study was to examine the effect of NZBC extract on 2 × 4 km time trial performance. Ten male cyclists (age: 30 ± 12 years, body mass: 74 ± 9 kg, height: 179 ± 7 cm, body fat: 11 ± 3%, (V̇) ̇O2max: 55 ± 7 mL•kg−1•min−1, mean ± SD) volunteered. Participants were familiarized with the time trials. Participants consumed capsulated NZBC extract (300 mg∙day−1 CurraNZ™; containing 105 mg anthocyanin) or placebo for seven days (double blind, randomised, cross-over design, wash-out at least seven days) before 2 × 4 km time trials (10 min active self-paced recovery between trials) (SRM ergometer, SRM International, Germany). Heart rate was recorded and blood lactate sampled immediately after each trial and 8 min into recovery between the trials. Times over comparable one km distances in each 4 km time trial were similar. No effect was observed for the time to complete the first (placebo: 380 ± 28 s, NZBC: 377 ± 27 s) and second 4 km of cycling (placebo: 391 ± 32 s, NZBC: 387 ± 30 s), within both groups the second 4 km times slower by 11 ± 8 s and 11 ± 9 s for placebo and NZBC, respectively. However, the total time of the two 4 km cycling trials was 0.82% faster with NZBC extract (placebo: 771 ± 60 s, NZBC 764 ± 56 s, p = 0.034) with seven participants having faster total times. There was no effect of NZBC on heart rate and lactate values at identical time points. New Zealand blackcurrant extract seems to be beneficial in repeated short-distance cycling time trials for overall performance.
      PubDate: 2017-05-09
      DOI: 10.3390/sports5020025
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 26: Injuries in Collegiate Women’s Volleyball: A
           Four-Year Retrospective Analysis

    • Authors: Christopher Sole, Ashley Kavanaugh, Michael Stone
      First page: 26
      Abstract: A four-year retrospective analysis of injury data was conducted on a collegiate (NCAA Division I) women’s volleyball team. Twenty athletes (Year 1: age = 19.4 ± 0.9 y, height = 175.2 ± 5.1 cm, body mass = 70.5 ± 10.2 kg; Year 2: age = 20.1 ± 1.0 y, height = 175.7 ± 4.7 cm, body mass = 69.5 ± 10.1 kg; Year 3: age = 20.1 ± 1.4 y, height = 173.8 ± 6.3 cm, body mass = 69.9 ± 10.8 kg; Year 4: age = 19.5 ± 1.4 y, height = 174.4 ± 8.6 cm, body mass = 72.7 ± 10.8 kg) participated in this study, accounting for 1483 total training exposures. Injury was defined as any damage to a body part, incurred during volleyball or strength and conditioning-related activities, which interfered with training and/or competition. Injury rate was normalized to the number of athletes and exposure and expressed as injuries per 1000 exposures. A total of 133 injuries were recorded. The most common injury was to the knee (left = 7.5%, right = 12.0%). Injuries occurred most often in volleyball practice (75.2%), followed by competition (20.3%), and strength and conditioning-related activities (4.5%). Non-contact injuries (upper body = 26.3%, lower body = 53.4%) were more common than contact injuries (upper-body = 13.5%, lower-body = 6.8%). An examination of injury rates relative to the training year revealed patterns in injury occurrence. Specifically, spikes in injury rate were consistently observed during periods of increased training volume that were preceded by breaks in organized training, such as the early pre-season and off-season training periods.
      PubDate: 2017-05-10
      DOI: 10.3390/sports5020026
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 27: Influence of Rest on Players’ Performance and
           Physiological Responses during Basketball Play

    • Authors: Robert Crowther, Anthony Leicht, Jessica Pohlmann, Jane Shakespear-Druery
      First page: 27
      Abstract: Pre-match warm-ups are standard in many sports but the focus has excluded the substitute players. The aim of this research was to investigate the result of inactivity on physiological and performance responses in substitute basketball players during competition. Two basketball players from the second tier of the State League of Queensland, Australia volunteered for this study and were assessed for performance (countermovement jump—CMJ) and physiological (core temperature via ingestible pill; skin temperature at the arm, chest, calf and thigh; heart rate—HR) responses prior to and following a 20-min warm-up, and during the first half of a competitive basketball match (2 × 20-min real time quarters). Warm up resulted in increases in CMJ (~7%), HR (~100 bpm) and core (~0.8 °C) and skin (~1.0 °C) temperatures. Following the warm up and during inactivity, substitute players exhibited a decrease in all responses including CMJ (~13%), HR (~100 bpm), and core (~0.5 °C) and skin (~2.0 °C) temperatures. Rest resulted in reductions in key performance and physiological responses during a competitive match that poses a risk for match strategies. Coaches should consider implementing a warm up to enhance core/skin temperature for substitute players immediately before they engage with competition to optimise player performance.
      PubDate: 2017-05-10
      DOI: 10.3390/sports5020027
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 28: Nutrition and Supplementation in Soccer

    • Authors: César Oliveira, Diogo Ferreira, Carlos Caetano, Diana Granja, Ricardo Pinto, Bruno Mendes, Mónica Sousa
      First page: 28
      Abstract: Contemporary elite soccer features increased physical demands during match-play, as well as a larger number of matches per season. Now more than ever, aspects related to performance optimization are highly regarded by both players and soccer coaches. Here, nutrition takes a special role as most elite teams try to provide an adequate diet to guarantee maximum performance while ensuring a faster recovery from matches and training exertions. It is currently known that manipulation and periodization of macronutrients, as well as sound hydration practices, have the potential to interfere with training adaptation and recovery. A careful monitoring of micronutrient status is also relevant to prevent undue fatigue and immune impairment secondary to a deficiency status. Furthermore, the sensible use of evidence-based dietary supplements may also play a role in soccer performance optimization. In this sense, several nutritional recommendations have been issued. This detailed and comprehensive review addresses the most relevant and up-to-date nutritional recommendations for elite soccer players, covering from macro and micronutrients to hydration and selected supplements in different contexts (daily requirements, pre, peri and post training/match and competition).
      PubDate: 2017-05-12
      DOI: 10.3390/sports5020028
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 29: Exercise, Osteoporosis, and Bone Geometry

    • Authors: Amy Harding, Belinda Beck
      First page: 29
      Abstract: Exercise is commonly recommended in the prevention and management of osteoporosis. The most common method to monitor bone mass and its response to interventions is bone densitometry. While closely associated with risk of fracture, densitometry-derived areal bone mineral density (aBMD) does not provide a reliable indication of bone geometry or morphological adaptation to stimuli. In fact, the effects of exercise interventions on aBMD are frequently modest, and may not fully represent the benefit of exercise to bone. Animal models suggest that mechanical loading indeed influences bone geometry and thus strength. Such an effect in humans has the potential to reduce osteoporotic fracture. The aim of the current narrative review is to provide an overview of what is known about the effects of exercise on bone geometry, with a focus on relevance to osteoporosis.
      PubDate: 2017-05-12
      DOI: 10.3390/sports5020029
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 30: Acute Effects of Block Jumps in Female
           Volleyball Players: The Role of Performance Level

    • Authors: Javier Brazo-Sayavera, Pantelis Nikolaidis, Alba Camacho-Cardenosa, Marta Camacho-Cardenosa, Rafael Timón, Pedro Olivares
      First page: 30
      Abstract: Although the role of jumping ability in female volleyball players is well recognised, the effect of fatigue on this ability is not well known. The aim of the present study was to examine the effect of a series of block jumps (BJ) on jumping ability and whether it varies by performance level. Ten elite (EG) and 11 amateur (AG) female volleyball players performed a fatigue intervention consisting of 45 BJ, being tested for squat jump (SJ), countermovement jump (CMJ) and BJ before and after the intervention. Elasticity index (EI): (100 × (CMJ − SJ)/SJ) and upper limbs coordination index (ULCI): (100 × (BJ − CMJ)/CMJ) were calculated. After the intervention, EG showed a decrease of 4.40% in BJ height (p = 0.04; ES = 0.40), whereas AG presented an increase of 1.27%, which was not significant (p = 0.57; ES = 0.07). However, EG and AG presented no significant differences in SJ (p = 0.965 and p = 0.655) and CMJ (p = 0.742 and p = 0.211) when comparing baseline with post-intervention. Although EI and ULCI showed no significant differences after intervention in any group (AG: p = 0.989 and p = 0.114; EG: p = 0.242 and p = 0.205, respectively), AG presented a medium effect size (ES = 0.50) in EI and a small one in ULCI (ES = 0.37), also EG showed a medium-large effect in ULCI (ES = 0.75). These findings suggest that EG performance in BJ tends to decrease at the end of a specific jump training practice. Therefore, coaches and fitness trainers working with elite volleyball players should focus on exercises to maintain jumping ability during a match.
      PubDate: 2017-05-16
      DOI: 10.3390/sports5020030
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 31: Does Avalanche Shovel Shape Affect Excavation
           Time: A Pilot Study

    • Authors: Kurt Schindelwig, Alexander Hoffmann, Martin Mössner, Werner Nachbauer
      First page: 31
      Abstract: In Europe and North America, approximately 150 fatalities occur as a result of avalanches every year. However, it is unclear whether certain shovel shapes are more effective than others in snow removal during avalanche victim recovery. The objective was to determine the performance parameters with a developed standardized test using different shovel shapes and to determine sex-specific differences. Hence, several parameters were determined for clearing the snow from a snow filled box (15 men, 14 women). A flat (F) and a deep (D) shovel blade with the shaft connected straight (S) or in clearing mode (C) were used for the investigation of the shovel shapes FS, DC and the subsequent use of DC&DS. Mean snow mass shifted per unit time increased significantly from 1.50 kg/s with FS to 1.71 kg/s (14%) with DS and further to 1.79 kg/s (4%) with DC&DS for all participants. Snow mass shifted per unit time was 44% higher (p < 0.05) for men than for women. In excavation operations, the sex-specific physical performance should be taken into account. The results were limited to barely binding snow, because only with this snow did the tests show a high reliability.
      PubDate: 2017-05-23
      DOI: 10.3390/sports5020031
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 32: Effects of 12 Weeks of Tai Chi Chuan Training on
           Balance and Functional Fitness in Older Japanese Adults

    • Authors: Nobuo Takeshima, Mohammod Islam, Yoshiji Kato, Daisuke Koizumi, Makoto Narita, Nicole Rogers, Michael Rogers
      First page: 32
      Abstract: The purpose of this study was to determine the effects of Tai Chi Chuan on static and dynamic balance, and functional fitness in older adults. Forty-nine volunteers were divided into an exercise group (EX: 9 men and 16 women, average age 72 ± 5 years) and control group (13 men and 11 women, average age 73 ± 6 years). The EX participated in a 12-week supervised exercise program (60 min/day, 2 days/week) that consisted of 10-min warm-up and stretching, 40-min Tai Chi Chuan exercise (long-form Yang style with 108 movements), and 10-min cool-down/relaxation exercises. The control group was asked to not change their physical activity habits. Static (sway velocity standing on firm or foam surfaces with eyes open or closed) and dynamic balance (limits of stability (LOS)), as well as functional fitness measures of body mass; upper- and lower-body strength; and flexibility, mobility, and aerobic fitness were taken before and after the intervention. After the 12-week Tai Chi Chuan exercise program, there were no improvements in any functional fitness or balance variable although components of LOS tended to increase (13.1%, p = 0.052). These results indicate that 12 weeks of Tai Chi Chuan exercise has no significant effect on balance and functional fitness parameters in older Japanese adults.
      PubDate: 2017-05-26
      DOI: 10.3390/sports5020032
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 33: Relationships between Bat Swing Speed and Muscle
           Thickness and Asymmetry in Collegiate Baseball Players

    • Authors: Ryo Tsuchikane, Takatoshi Higuchi, Tadashi Suga, Michio Wachi, Jun Misaki, Daichi Tanaka, Yuto Miyake, Tadao Isaka
      First page: 33
      Abstract: The purpose of the present study was to examine the relationships between bat swing speed (BSS), muscle thickness, and muscle thickness asymmetry in collegiate baseball players. Twenty-four collegiate baseball players participated in this study. Maximum BSS in hitting a teed ball was measured using a motion capture system. The muscle thicknesses of the trunk (upper abdominal rectus, central abdominal rectus, lower abdominal rectus, abdominal wall, and multifidus lumborum), upper limb, and lower limb were measured using a B-mode ultrasonography. Lateral asymmetry between each pair of muscles was determined as the ratio of the thickness of the dominant side to that of the non-dominant side. Statistically significant positive correlations were observed between BSS and muscle thicknesses of the abdominal wall and multifidus lumborum on the dominant side (r = 0.426 and 0.431, respectively; p < 0.05), whereas only trends against this significance were observed between BSS and muscle thicknesses on the non-dominant side. No statistical correlations were found between BSS and the lateral asymmetry of any muscles. These findings indicate the importance of the trunk muscles for bat swing, and the lack of association between BSS and lateral asymmetry of muscle size.
      PubDate: 2017-06-02
      DOI: 10.3390/sports5020033
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 34: A Comparison of Implicit and Explicit Motor
           

    • Authors: Maliheh Sarabandi
      First page: 34
      Abstract: This study tends to assess implicit and explicit types of motor learning in patients with Multiple Sclerosis (MS) and normal peers by means of a serial reaction time. Sample size was 15 for each group and Samples included 30 patients with MS and 30 normal peers and were assigned to implicit and explicit learning groups. A repeated measures ANOVA was used for measuring reaction time and response error, and a paired samples t-test was used to compare regular and irregular sequence data in each group. Comparison of these two types of learning in speed (response time) and accuracy (number of errors) showed the number of errors (P = 0.012) and response time (P = 0.012) in the implicit motor learning group of MS patients and the number of errors (P = 0.096) and response time (P = 0.954) in the explicit motor learning group of MS patients. Moreover, comparison showed the number of errors (P = 0.008) and response time (P = 0.05) in the implicit group of normal peers and the number of errors (P = 0.011) and response time (P = 0.442) in the explicit group of normal peers. The results showed that explaining and describing the task is less effective at training the motor sequence of MS patients and that these patients benefit more from implicit learning.
      PubDate: 2017-06-07
      DOI: 10.3390/sports5020034
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 35: Muscular Power during a Lifting Task Increases
           after Three Months of Resistance Training in Overweight and Obese
           Individuals

    • Authors: Erika Zemková, Ol’ga Kyselovičová, Michal Jeleň, Zuzana Kováčiková, Gábor Ollé, Gabriela Štefániková, Tomáš Vilman, Miroslav Baláž, Timea Kurdiová, Jozef Ukropec, Barbara Ukropcová
      First page: 35
      Abstract: Background: This study evaluates the effect on power produced during a modified lifting task in the overweight and obese after three months of either resistance or aerobic training. Methods: Seventeen male subjects divided randomly into two groups performed deadlift and deadlift high pull, both with increasing weights up to maximal power, prior to and after the training programs (three sessions per week). Results: Their mean power increased significantly during the deadlift at 20 kg (14.3%, p = 0.026), 30 kg (17.7%, p = 0.008), 40 kg (16.5%, p = 0.011), 50 kg (14.5%, p = 0.020), and 60 kg (14.3%, p = 0.021) and during the deadlift high pull at 30 kg (9.9%, p = 0.037), 40 kg (10.1%, p = 0.035), and 50 kg (8.2%, p = 0.044) after the resistance training. However, the group that participated in the aerobic training failed to show any significant changes in power performance during either the deadlift or deadlift high pull. Conclusion: Three months of resistance training enhances power outputs during a lifting task with weights from 30 to 50 kg (~40%–60% of 1-repetition maximum) in the overweight and obese. Because this test was sensitive in revealing pre-post training changes in lifting performance, it should be implemented in the functional diagnostics for overweight and obese individuals and also complement existing testing methods.
      PubDate: 2017-06-08
      DOI: 10.3390/sports5020035
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 36: Ingestion of an Amino Acid Electrolyte Beverage
           during Resistance Exercise Does Not Impact Fluid Shifts into Muscle or
           Performance

    • Authors: JohnEric Smith, Ben Krings, Timothy Peterson, Jaden Rountree, Roksana Zak, Matthew McAllister
      First page: 36
      Abstract: The purpose of this study was to investigate the impact of ingesting an amino acid-electrolyte (AAE) beverage during upper body resistance exercise on transient muscle hypertrophy, exercise performance, markers of muscle damage, and recovery. Participants (n = 15) performed three sets of six repetitions—bench press, lat pull down, incline press, and seated row—followed by three sets of eight repetitions at 75% of the estimated 1 repetition maximum—triceps kickback, hammer curl, triceps push down, and preacher curl—with 90 s of rest between sets. The final set of the push down/preacher curl was performed to failure. Prior to and immediately post-exercise, as well as 24, 48, and 72 h post exercise, cross-sectional muscle thickness was measured. Blood samples were collected prior to exercise, as well as 24, 48, and 72 h post-exercise for serum creatine kinase (CK) analysis. No treatment effect was found for muscle cross-sectional area, repetitions to failure, or serum CK. A main effect (p < 0.001) was observed in the change in serum CK levels in the days following the resistance exercise session. The findings of this study suggest that the acute ingestion of a AAE beverage does not alter acute muscle thickness, performance, perceived soreness and weakness, or markers of muscle damage.
      PubDate: 2017-06-10
      DOI: 10.3390/sports5020036
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 37: Functional Movement Screening and Paddle-Sport
           Performance

    • Authors: Andrew Hatchett, Charles Allen, Jake St. Hilaire, Alex LaRochelle
      First page: 37
      Abstract: The purpose of the study reported here was to determine the relationship between an endurance paddle-sport athlete’s total functional movement screening (FMS) score and individual race performance. Fifty elite level endurance canoeists and kayakers completed the seven-stage FMS protocol prior to the 2016 United States Canoe and Kayak Association National Championship race. Time taken to finish the race was then associated to overall FMS score and respective sub-scores. Total FMS score and various sub-scores were significantly related to race performance. Female and male athletes differed in which sub-scores were shown to be significantly correlated to finishing time. Outcomes from this study indicate that limitations in functional movement are related to endurance paddle-sport race performance.
      PubDate: 2017-06-13
      DOI: 10.3390/sports5020037
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 38: What is Trained Develops! Theoretical
           Perspective on Skill Learning

    • Authors: Hermundur Sigmundsson, Leif Trana, Remco Polman, Monika Haga
      First page: 38
      Abstract: Knowledge about developmental theories is important for experts or specialists working with children following normal development and children who have various kinds of dysfunction, in order to better understand what happens with processes associated with motor behavior. In this article, we have explored how theories of development and learning can be used to understand processes associated with motor behavior. A probabilistic perspective emphasizes that the changes taking place in the development is a result of interaction: structural changes in the nervous system leading to changes in function and behavior and opposite, functional changes resulting in changes in structure. This bidirectional interaction between biological and experiential aspects is a continuous process which cannot be reduced to either organism or environment. Dynamical systems theory (DST) emphasizes that it is the interaction between the person, the environment, and the task that changes how our movements are, also in terms of how we develop and learn new movements. The interplay between these factors will, over time, lead to changes in motor development. The importance of experience is central to Edelman's theory of neuronal group selection (NGST). Activation of the nervous system increases the connections between certain areas of the brain, and the selection processes in the brain are a result of enhancement of neural connections involved in a "successful" motion. The central nervous system adapts its structure and function in response to internal and external influences, and hence neural plasticity is a prerequisite for learning and development. We argue that Edelman´s approach supports the theory of specificity of learning. From the perspectives of probabilistic epigenesis, DST, and NGST, we can see that being physically active and having the opportunity to get different movement experiences are of great significance for promoting motor development and learning. A variation of purposeful or rewarding physical activity in a variety of contexts will provide individual opportunities for changes of behavior in terms of both quantitative and qualitative changes in motor development.
      PubDate: 2017-06-15
      DOI: 10.3390/sports5020038
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 39: Prevalence of Injuries during Brazilian
           Jiu-Jitsu Training

    • Authors: Alex R. McDonald, Fred A. Murdock Jr., Josh A. McDonald, Christopher J. Wolf
      First page: 39
      Abstract: Brazilian jiu-jitsu (BJJ) is a martial art that focuses on groundwork, joint locks, and chokeholds. The purpose of this study is to determine the prevalence of injuries sustained during BJJ training. A 27-question research survey was e-mailed to 166 BJJ gyms in the United States. Demographic information, belt level, weight class, training hours, competition experience, and injury prevalence data were collected. The majority of respondents were Caucasian (n = 96) males (n = 121) with an average age of 30.3 years. Overall, the most common injury locations were to the hand and fingers (n = 70), foot and toes (n = 52), and arm and elbow (n = 51). The most common medically diagnosed conditions were skin infections (n = 38), injuries to the knee (n =26), and foot and toes (n = 19). The most common non-medically diagnosed injuries occurred to the hand and fingers (n = 56), arm and elbow (n = 40), and foot and toes (n = 33). In general, athletes were more likely to sustain distal rather than proximal injuries. Athletes reported more frequent medically diagnosed injuries to the lower extremity and more frequent self-diagnosed injuries to the upper extremity. Upper extremity injuries appear to be more frequent but less severe than lower extremity injuries with the opposite being true for lower extremity injuries.
      PubDate: 2017-06-12
      DOI: 10.3390/sports5020039
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 40: Active Recovery between Interval Bouts Reduces
           Blood Lactate While Improving Subsequent Exercise Performance in Trained
           Men

    • Authors: Harutiun M. Nalbandian, Zsolt Radak, Masaki Takeda
      First page: 40
      Abstract: This study aimed to examine the blood lactate and blood pH kinetics during high-intensity interval training. Seventeen well-trained athletes exercised on two different occasions. Exercises consisted of three 30 s bouts at a constant intensity (90% of peak power) with 4 min recovery between bouts followed by a Wingate test (WT). The recoveries were either active recovery (at 60% of the lactate threshold intensity) or passive recovery (resting at sitting position). During the exercise, blood samples were taken to determine blood gasses, blood lactate, and blood pH, and peak and average power were calculated for the WT. When performing the active recovery trials, blood pH was significantly higher (p < 0.01) and blood lactate was significantly lower (p < 0.01) compared with the passive recovery trials. WT performance was significantly higher in the active recovery trials: peak power was 671 ± 88 and 715 ± 108 watts, and average power was 510 ± 70 and 548 ± 73 watts (passive and active respectively; p < 0.01). However, no statistically significant correlations were found between the increased pH and the increased performance in the active recovery trials. These results suggest that active recovery performed during high-intensity interval exercise favors the performance in a following WT. Moreover, the blood pH variations associated with active recovery did not explain the enhanced performance.
      PubDate: 2017-06-12
      DOI: 10.3390/sports5020040
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 41: Link between Motor Competence and Health Related
           Fitness in Children and Adolescents

    • Authors: Carlos Luz, Rita Cordovil, Gabriela Almeida, Luis Rodrigues
      First page: 41
      Abstract: This study examined motor competence (MC) behavior in 6- to 14-year-old children, and investigated the differences in health-related fitness (HRF) between high and low MC groups, according to sex and age. A sample of 564 children (288 males) participated in this study, divided into three age groups (6–8 years; 9–11 years; 12–14 years). Total MC and its three components (stability, locomotor, and manipulative) were assessed with a quantitative instrument. HRF was evaluated using a maximal multistage 20-m shuttle-run test and the handgrip test. Participants were divided into tertiles according to their MC level and high and low MC groups were analyzed. Overall, MC increased across age groups for both sexes, but boys presented better results than girls. The high MC group outperformed their low MC peers in all HRF variables, independent of their age group. Although cardiovascular fitness increased with age for both the high and low MC groups, the differences between these groups were greater in older children compared to younger children, within the study age range. The findings suggest that MC interventions should be considered as an important strategy to enhance HRF, and girls at a young age should be a priority target.
      PubDate: 2017-06-15
      DOI: 10.3390/sports5020041
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 42: The Role of Eccentric Strength in 180°
           Turns in Female Soccer Players

    • Authors: Paul Jones, Christopher Thomas, Thomas Dos’Santos, John McMahon, Philip Graham-Smith
      First page: 42
      Abstract: Previous studies have reported an association between eccentric strength (ECC-STR) and change of direction (COD) ability. Little is known about how ECC-STR facilitates COD maneuvers. The aim of this study was to examine the role of ECC-STR during a 180° COD task in 18 female soccer players. Each player performed six trials of a 180° COD task whereby three-dimensional motion data from 10 Qualisys Pro-Reflex infrared cameras (240 Hz) and ground reaction forces (GRFs) from two AMTI force platforms (1200 Hz) were collected. Relative eccentric knee extensor (ECC-EXT) and flexor (ECC-FLEX) peak torque was collected from both limbs at 60°·s−1 using a Kin Com isokinetic dynamometer. Large correlations were revealed between COD performance (time to complete 5 m approach, 180° turn, 5 m return) and ECC-EXT (R = −0.674) and ECC-FLEX (R = −0.603). Moderate to large correlations were observed between approach velocity (AV) and COD performance (R = −0.484) and ECC-EXT (R = 0.724). Stronger participants (n = 9) recorded significantly (p < 0.05) faster AV (4.01 ± 0.18 vs. 3.74 ± 0.24 m·s−1, d = 1.27) and a greater reduction in velocity (−1.55 ± 0.17 vs. −1.37 ± 0.21 m·s−1, d = −0.94) during penultimate contact than weaker (n = 9) subjects. Greater ECC-STR is associated with faster COD performance in female soccer players, as stronger players are better able to decelerate during penultimate contact from faster approach velocities.
      PubDate: 2017-06-17
      DOI: 10.3390/sports5020042
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 43: The Relationship between Fundamental Motor Skill
           Proficiency and Participation in Organized Sports and Active Recreation in
           Middle Childhood

    • Authors: Stephanie Field, Viviene Temple
      First page: 43
      Abstract: Motor skill proficiency in middle childhood is associated with higher physical activity levels at that age and is predictive of adolescent physical activity levels. Much of the previous research in this area has used accelerometry in determining these relationships, and as a result, little is known about what physical activities the children are engaging in. Therefore the aim of this study was to examine rates of participation in physical activities, the relationships between motor proficiency and how often children participate, and if there were gender-based differences in participation, motor skills, or the relationship between these variables. Participants were 400 boys and girls (Mean age = 9 years 6 months) in grade 4. Motor skills were assessed using the Test of Gross Motor Development-2 (TGMD-2) and physical activity participation was measured using the Children’s Assessment of Participation and Enjoyment (CAPE). Descriptive statistics, chi-squared analyses, and multivariate analysis of variance (MANOVA) were used to examine activity patterns and whether these patterns differed by gender. Correlation coefficients were used to estimate the relationships between fundamental motor skill proficiency and participation. The boys and girls participated in many of the same activities, but girls were more likely to participate in most of the informal physical activities. More boys than girls participated in team sports, boys participated more frequently in team sports, and the boys’ object control and locomotor skill proficiency were significantly associated with participation in team sports. There were some significant associations between motor skills and participation in specific activities; however it is not clear if participation is developing skillfulness or those who are more skilled are engaging and persisting with particular activities.
      PubDate: 2017-06-18
      DOI: 10.3390/sports5020043
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 44: The Effect of Teaching Games of Understanding as
           a Coaching Instruction had on Adjust, Cover and Heart Rate among Malaysian
           and Indian Junior Hockey Players

    • Authors: Sanmuga Nathan
      First page: 44
      Abstract: The field hockey coaching process across both Malaysia and India favours a traditional, coach-centred approach of mastering technical skills in terms of game play parameters, fitness, intensity, and load training, whereas a tactical- and player-centred pedagogical approach still takes a backseat. On the other hand, the Teaching Games for Understanding (TGfU) model offers tactical-cognitive instruction and is gaining international recognition for its ability to produce intelligent players via a problem-solving approach in game play. Therefore, the purpose of this quasi-experimental study was to investigate the effect of TGfU compared to skill mastery instruction, termed as Skill Drill Technical (SDT), among Malaysian and Indian elite junior hockey players in term of the game play attributes of adjust and cover in 5 vs. 5 small-sided game play and game play intensity via heart rate (HR) at different points of game play. A total of n = 60 players with an average age of 15 ± 1.03 was selected via simple random sampling from both countries involved in this study and assigned equally to groups, with 15 per group for TGfU and for SDT across Malaysia and India. Gathered data were analysed using the ANOVA and ANCOVA techniques. Findings indicated that there were no significant differences for adjust in 5 vs. 5 game play between TGfU and SDT across Malaysia and India after the intervention. For cover, there was significant improvement for Malaysian players using the TGfU model compared to SDT. In contrast, there was no significant difference between these two models among the Indian players after the intervention. There was significant difference between these two models in terms of warm-up HR across the two countries, and HR was higher via TGfU. For HR immediately after the 5 vs. 5 game play intervention and HR after three minutes’ recovery, Indian players with TGfU recorded a higher and significant difference compared to SDT. However, findings indicated no significant difference between these two instruction types among Malaysians, although TGfU proved to have higher HR intensity. Therefore, these findings reiterated that TGfU is a useful approach for game play to enhance intensity and cardiac output. In conclusion, for TGfU to be more relevant to the coaching environment, future research should link game play and physiological parameters. TGfU should able to overcome the barriers of tradition and cultural background that may hinder its momentum.
      PubDate: 2017-06-20
      DOI: 10.3390/sports5020044
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 45: Energy Expenditure, Availability, and Dietary
           Intake Assessment in Competitive Female Dragon Boat Athletes

    • Authors: Jun Ong, Iain Brownlee
      First page: 45
      Abstract: Dragon boat racing requires high physical activity levels during competition and training. The female athletic triad refers to a number of negative health consequences (e.g., amenorrhoea, low bone mineral density, and low energy availability) that may result from high physical activity in female athletes in parallel with inadequate dietary intake. This study aimed to estimate energy expenditure and dietary adequacy in female competitive dragon boat athletes. Following ethical approval, energy expenditure was assessed by use of SensewearTM armbands (which measure movement as well as galvanic heat loss) on nine dragon boat athletes preparing for the Southeast Asian Games 2013. The mean estimated energy expenditure for the athletes was 2226 ± 711 kJ/day. Mean total energy, recorded using three-day food diaries (6715 ± 2518 kJ/day) and energy availability (99 ± 56 kJ/kg/day), were low. Estimated micronutrient intake (calcium 699.3 ± 328.7 mg/day and iron 10.6 ± 4.7 mg/day) did not meet recommended daily allowances of 800 mg/day and 19 mg/day, respectively. The low intake of energy, calcium, and iron noted within this study could have negative effects on performance and short- and long-term health in female dragon boat athletes.
      PubDate: 2017-06-21
      DOI: 10.3390/sports5020045
      Issue No: Vol. 5, No. 2 (2017)
       
  • Sports, Vol. 5, Pages 2: Content Validity and Psychometric Properties of
           the Nomination Scale for Identifying Football Talent (NSIFT): Application
           to Coaches, Parents and Players

    • Authors: Alejandro Prieto-Ayuso, Juan Pastor-Vicedo, Onofre Contreras-Jordán
      First page: 2
      Abstract: The identification of football talent is a critical issue both for clubs and the families of players. However, despite its importance in a sporting, economic and social sense, there appears to be a lack of instruments that can reliably measure talent performance. The aim of this study was to design and validate the Nomination Scale for Identifying Football Talent (NSIFT), with the aim of optimising the processes for identifying said talent. The scale was first validated through expert judgment, and then statistically, by means of an exploratory factor analysis (EFA), confirmatory factor analysis (CFA), internal reliability and convergent validity. The results reveal the presence of three factors in the scale’s factor matrix, with these results being confirmed by the CFA. The scale revealed suitable internal reliability and homogeneity indices. Convergent validity showed that it is teammates who are best able to identify football talent, followed by coaches and parents. It can be concluded that the NSIFT is suitable for use in the football world. Future studies should seek to confirm these results in different contexts by means of further CFAs.
      PubDate: 2017-01-01
      DOI: 10.3390/sports5010002
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 3: Effect of Number of Players and Maturity on
           Ball-Drills Training Load in Youth Basketball

    • Authors: Daniele Conte, Terence Favero, Meike Niederhausen, Laura Capranica, Antonio Tessitore
      First page: 3
      Abstract: This study aimed to assess the basketball ball-drills workload analyzing: (1) the effect of varying the number of players involved on physiological and technical demands; (2) the temporal changes in players’ responses across bouts; and (3) the relationship of players’ workload with their maturation status and training age. Twelve young male basketball players (mean ± SD; age 13.9 ± 0.7 years; height 1.76 ± 0.06 m; body mass 65.7 ± 12.5 kg; HRmax 202 ± 8 beat·min−1) completed three bouts of 4 min interspersed by 2 min of passive recovery of two vs. two and four vs. four ball-drills. The mean percentage of HRmax (%HRmax) and ratings of perceived exertion (RPE) were collected. Technical actions (TAs) (dribbles, passes, shots, interceptions, steals, rebounds, and turnovers) were calculated through notational analysis. Players’ genitalia development (GD) and pubic hair (PH) growth were assessed using Tanner scale. Results showed a higher %HRmax (p = 0.018), RPE (p = 0.042), dribbles (p = 0.007), shots (p = 0.003), and rebounds (p = 0.006) in two vs. two compared to four vs. four condition. Furthermore, a statistical difference was found for %HRmax (p = 0.005) and number of passes (p = 0.020) between bouts. In addition, no correlation between GD, PH, and training age with %HRmax, RPE, and TAs was found. These findings suggest that variations of the number of players involved affect ball-drills workload and that ball-drills training intensity varies across bouts. Finally, ball-drills elicit an adequate training stimulus, regardless of players’ maturation status and training age.
      PubDate: 2017-01-02
      DOI: 10.3390/sports5010003
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 4: Poorer Intermittent Sprints Performance in
           Ramadan-Fasted Muslim Footballers despite Controlling for Pre-Exercise
           Dietary Intake, Sleep and Training Load

    • Authors: Abdul Aziz, Ahmad Che Muhamad, Siti Roslan, Nazirah Ghulam Mohamed, Rabindarjeet Singh, Michael Chia
      First page: 4
      Abstract: This study examines the effects of Ramadan fasting on sprint performance during prolonged intermittent exercise in trained Muslim footballers, under controlled pre-exercise conditions. A within-group, cross-over study design with two non-fasted or Control trials performed before (i.e., CON1) and after (CON2) the Ramadan month, and with the Ramadan-fasted (RAM) trials performed within the Ramadan month. After familiarization, 14 players completed a modified 60-min (4 × 15-min exercise blocks interspersed with 3-min intervals) of the Loughborough Intermittent Shuttle Test (mLIST) of fixed speeds of walking, jogging, running, but with all-out effort sprints. During the interval periods, capillary blood glucose and blood lactate measures were taken, rectal and skin temperatures were recorded and maximal voluntary isometric contractions (MVIC) of the dominant leg and hand-grip were performed to provide some indication to the cause(s) of ‘fatigue’ during exercise. Players were provided with standardized 24-h pre-packed meals prior to all trials. Sleep hours were objectively assessed and perceived training loads were monitored and these were equivalent between RAM and CON trials. Sprint times throughout mLIST were significantly faster in both CON1 and CON2 as compared to RAM trials (all P < 0.017; d = small to moderate), and this poorer performance in RAM was observed as early as during the first 15-min of the mLIST. Blood markers, MVIC and thermoregulatory results were not substantially different between both CON and RAM trials. In conclusion, despite similarities in dietary intake, sleeping hours and training loads between conditions, results still indicate that Ramadan fasting had an adverse effect on prolonged intermittent performance. Nocebo effects plays a dominant role during exercise in the Ramadan-fasted state.
      PubDate: 2017-01-06
      DOI: 10.3390/sports5010004
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 5: Soccer and Relative Age Effect: A Walk among
           Elite Players and Young Players

    • Authors: Manuel Sierra-Díaz, Sixto González-Víllora, Juan Pastor-Vicedo, Jaime Serra-Olivares
      First page: 5
      Abstract: Grouping people according to chronological age is popular in fields such as education and sport. Athletes who are born in the first months of the year usually have cognitive and physical development differences in contrast to those born in the last months of the same year. That is why competitive teams tend to select older players more often than youngsters. Age differences between athletes born in the same year as well as an over-representation of older players are known as the Relative Age Effect. This effect is extensively described in young and elite team sports such as basketball, volleyball or, ice-hockey, as well as in soccer. The purpose of this study is to examine the state-of-the-art of the Relative Age Effect in youth and elite soccer players. This review summarizes recent research articles on the Relative Age Effect related to competitive soccer from 2010 to 2016. The systematic literature search was conducted in four databases: SPORTDiscus, Medline, EBSCO host and Google Scholar. Although causes and final solutions have not been clearly achieved yet, it is necessary to continue investigating this phenomenon in order to provide a starting point for future research.
      PubDate: 2017-01-11
      DOI: 10.3390/sports5010005
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 6: Acknowledgement to Reviewers of Sports in 2016

    • Authors: Sports Editorial Office
      First page: 6
      Abstract: The editors of Sports would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2016. [...]
      PubDate: 2017-01-12
      DOI: 10.3390/sports5010006
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 7: Effect of Post-Exercise Whole Body Vibration with
           Stretching on Mood State, Fatigue, and Soreness in Collegiate Swimmers

    • Authors: Justin Merrigan, Matthew Tynan, Jonathan Oliver, Andrew Jagim, Margaret Jones
      First page: 7
      Abstract: Static stretching (SS) during whole body vibration (WBV) has been suggested for exercise recovery. The purpose was to compare post-exercise self-ratings of fatigue (FAT), mood state (BAM), soreness (SOR), and perceived exertion (RPE) between SS and WBV+SS in swimmers (9 women, mean ± SD: 19.3 ± 1.3 year, 171 ± 5.7 cm, 67.6 ± 7.2 kg, 26.6 ± 4.1 %body fat (%BF); 10 men, mean ± SD: 19.7 ± 1.0 year, 183 ± 5.5 cm, 77.1 ± 4.2 kg, 13.1 ± 2.2 %BF). Athletes were divided by sex, event (sprint, distance), and assigned to SS or WBV+SS. Both conditions consisted of SS performed on the WBV platform with or without WBV (50 Hz, 6 mm). Sessions consisted of: pre and post measures of BAM, FAT, SOR; the condition; and RPE. Mixed factorial ANOVA were run. A significant condition by pre/post interaction was observed (p = 0.035). Post hoc analyses showed WBV+SS elicited lower post-exercise ratings of FAT (p = 0.002) and the BAM affective states, of tension (p = 0.031), and fatigue (p = 0.087). RPE did not differ between conditions. Of interest is the decrease in tension and fatigue noted by the BAM. Mood state can be indicative of how athletes adapt to training volume and intensity.
      PubDate: 2017-01-13
      DOI: 10.3390/sports5010007
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 8: Sex Differences in Countermovement Jump Phase
           Characteristics

    • Authors: John McMahon, Sophie Rej, Paul Comfort
      First page: 8
      Abstract: The countermovement jump (CMJ) is commonly used to explore sex differences in neuromuscular function, but previous studies have only reported gross CMJ measures or have partly examined CMJ phase characteristics. The purpose of this study was to explore differences in CMJ phase characteristics between male and female athletes by comparing the force-, power-, velocity-, and displacement-time curves throughout the entire CMJ, in addition to gross measures. Fourteen men and fourteen women performed three CMJs on a force platform from which a range of kinetic and kinematic variables were calculated via forward dynamics. Jump height (JH), reactive strength index modified, relative peak concentric power, and eccentric and concentric displacement, velocity, and relative impulse were all greater for men (g = 0.58–1.79). Relative force-time curves were similar between sexes, but relative power-, velocity-, and displacement-time curves were greater for men at 90%–95% (immediately before and after peak power), 47%–54% (start of eccentric phase) and 85%–100% (latter half of concentric phase), and 65%–87% (bottom of countermovement and initial concentric phase) of normalized jump time, respectively. The CMJ distinguished between sexes, with men demonstrating greater JH through applying a larger concentric impulse and, thus, achieving greater velocity throughout most of the concentric phase, including take-off.
      PubDate: 2017-01-19
      DOI: 10.3390/sports5010008
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 9: Functional Assessment and Injury Risk in a
           Professional Soccer Team

    • Authors: Pedro Gómez-Piqueras, Sixto González-Víllora, María Sainz de Baranda Andújar, Onofre Contreras-Jordán
      First page: 9
      Abstract: At the last World Conference on Sport and Physical Therapy celebrated in Bern (Switzerland, 2015), it was confirmed that the functional skills of an athlete are a very important variable to be considered in the recovery of an injury. On the other hand, its use as a predictive risk tool still lacks solid evidence. The purpose of this study was to determine whether a battery of functional tests (FPT) could be used as a preliminary measure for the season in order to identify the injury risk in a professional soccer team in the Spanish Second Division B League. Fifty-two soccer players (ages of 25.3 ± 4.6 years, 10.33% ± 0.9% fat) were functionally assessed during two seasons (2012–2013 and 2013–2014) and analyzed from an injury perspective. A total of 125 injuries were recorded. The sample was grouped based on the number of injuries and the required absence days. Except for the bipodal vertical jump (CMJ), none of the functional tests revealed differences among the groups. The correlation study between the functional condition and the suffered injuries did not show any significant results.
      PubDate: 2017-01-22
      DOI: 10.3390/sports5010009
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 10: Change of Muscle Activity as Well as Kinematic
           and Kinetic Parameters during Headers after Core Muscle Fatigue

    • Authors: Stephan Becker, Michael Fröhlich, Jens Kelm, Oliver Ludwig
      First page: 10
      Abstract: In soccer, headers are a tactical measure and influenced by numerous factors. The goal of this study was to identify whether changes in kinematics and muscular activity, especially of the head-stabilizing muscles, occur during headers when the core musculature is fatigued. In two subgroups, muscular activity (12 amateur players, age 23.6 ± 4.2 years) and kinematics and dynamics (29 amateur players, age 23.7 ± 2.8 years) were examined during straight headers on a pendulum header. Data were collected before and after the core muscles were fatigued by an exercise program. Telemetric surface EMG, 3D acceleration sensor, force plate, and video recordings were used. Under fatigue, the activity of M. erector spinae and M. rectus abdominis was significantly reduced in the preparation phase of the header. The activity of M. sternocleidomastoideus was significantly increased during the jump phase, and the hip extension angle during maximum arched body tension was significantly reduced under fatigue. Jumping height, acceleration force impulse, and linear head acceleration were also significantly reduced. We conclude that fatigue of the core muscles affects the motion technique of the header and the activity of the muscle groups stabilizing the head. Therefore, the necessity of specific training in soccer should be emphasized from a medical-preventive point of view.
      PubDate: 2017-01-22
      DOI: 10.3390/sports5010010
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 11: Use of Non-Steroidal Anti-Inflammatory Drugs
           among Participants in a Mountain Ultramarathon Event

    • Authors: Sonia Martínez, Antoni Aguiló, Carlos Moreno, Leticia Lozano, Pedro Tauler
      First page: 11
      Abstract: The aim of this study was to evaluate and compare the prevalence of non-steroidal anti-inflammatory drugs (NSAID) consumption immediately before, during and immediately after three mountain ultra-endurance runs that differed in their course distance. This observational study took place at the Ultra Mallorca Serra de Tramuntana (Mallorca, Spain), an ultra-endurance mountain event with runners participating either in a 112-km (Ultra, n = 58), a 67-km (Trail, n = 118) or a 44-km (Marathon, n = 62) run competition. Participants in the study answered, within an hour after finishing the competition, a questionnaire focused mainly on NSAIDs consumption. Among study participants, 48.3% reported taking NSAIDs at least for one of the time-points considered: before, during and/or immediately after the competition, with more positive responses (having taken medication) found for the Ultra (60.3%) than for the Trail (49.2%) and the Marathon (35.5%). Among consumers, the Ultra participants reported the lowest intake before and the highest during the race, while participants in the Marathon reported similar consumption levels before and during the race. In conclusion, a high prevalence of NSAID consumption was found among athletes participating in an ultra-endurance mountain event. Competition duration seemed to determine both the prevalence and the chronological pattern of NSAID consumption.
      PubDate: 2017-01-29
      DOI: 10.3390/sports5010011
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 12: Seasonal Variation of Agility, Speed and
           Endurance Performance in Young Elite Soccer Players

    • Authors: Michal Dragijsky, Tomas Maly, Frantisek Zahalka, Egon Kunzmann, Mikulas Hank
      First page: 12
      Abstract: The aim of this study was to investigate changes in the linear running speed (LRS) for 30 m, change of direction speed (CODS), and endurance in young elite Czech soccer players. The following tests were conducted to assess CODS and endurance: Agility 505 turning toward the dominant (A505DL) and non-dominant lower limb (A505NL); Illinois Agility Test (IAT); and intermittent test (Yo-Yo IRT1). During the soccer season, we investigated performance at the following time periods: the start (t1) and the end of the pre-season period (t2); during (t3) and at the end of the competitive period (t4). Repeated measurement analysis of variance revealed a significant effect of time period on selected fitness parameters (p < 0.05). Post hoc analysis for test A505DL revealed significant improvements of performance at t3 (2.71 ± 0.08 s) and t4 (2.72 ± 0.06 s) compared to t1 (2.81 ± 0.09 s). A505NL was significantly different between t1 (2.83 ± 0.09 s) and t2 (2.76 ± 0.09 s), t3 (2.7 ± 0.07 s) and t4 (2.71 ± 0.09 s). Performance of CODS at t1 for the IAT (18.82 ± 0.56 s) was significantly lower (p < 0.05) than any other time period (t2 = 18.52 ± 0.63 s, t3 = 17.94 ± 0.51 s, t4 = 17.89 ± 0.66 s). The power of LRS was significantly different at t3 (4.99 ± 0.15 s), and t4 (4.98 ± 0.17 s) compared to t1 (5.15 ± 0.21 s), and t2 (5.07 ± 0.14 s). For the Yo-Yo IRT1 test, we observed a significant increase in performance between t1 (625.26 ± 170.34 m), t2 (858.95 ± 210.55 m), and t3 (953.68 ± 229.88 m). These results show the impact of soccer season time period on young soccer player performance and may further serve as a basis for comparison with similar research conducted by peers. These results may aid sports practice for clinicians, conditioning coaches, soccer coaches and physiotherapeutic coaches.
      PubDate: 2017-02-04
      DOI: 10.3390/sports5010012
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 13: The Influence of Exercise Training on Quality of
           Life and Psychosocial Functioning in Children with Congenital Heart
           Disease:A Review of Intervention Studies

    • Authors: Karolijn Dulfer, Willem Helbing, Elisabeth Utens
      First page: 13
      Abstract: Children and adolescents operated upon for congenital heart disease may show reduced exercise capacity and physical activity, associated with lowered quality of life. This review presents intervention studies on the influence of an exercise program on quality of life and psychosocial functioning in children with severe congenital heart disease. Participation in an exercise program among young people with complex congenital heart disease seemed to have positive effects on quality of life and passive leisure time spent. However, more effects of the exercise programs may have been expected. For future research it is important to critically evaluate the content of the exercise programs.
      PubDate: 2017-02-10
      DOI: 10.3390/sports5010013
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 14: Differences in the Dominant and Non-Dominant
           Knee Valgus Angle in Junior Elite and Amateur Soccer Players after
           Unilateral Landing

    • Authors: Oliver Ludwig, Steven Simon, Joe Piret, Stephan Becker, Franz Marschall
      First page: 14
      Abstract: More than 70% of all knee injuries in soccer occur in non-contact situations. It is known that increased lower limb dynamic knee valgus is associated with such situations. Little has been found out about differences in knee kinematics of the dominant (kicking) and non-dominant (supporting) leg during a single leg landing. A total of 114 male adolescent soccer players (age 14.6 ± 1.1 years) from elite (N = 66) and amateur soccer clubs (N = 48) performed a single leg drop landing down from a box. For each leg, the two-dimensional dynamic knee valgus angle (DKVA) was calculated. Paired t-tests were used to statistically determine significant differences between dominant and non-dominant leg DKVA, and t-tests were calculated between the two performance groups. Statistically significant differences (p < 0.05) were identified for the DKVA between the dominant and non-dominant leg for both amateur and elite players, showing a greater DKVA for the dominant leg. Group differences for the DKVA between amateur and elite players were not found, neither for the dominant, nor for the non-dominant leg. It can be concluded that the non-dominant leg showed more stable dynamics than the dominant leg during unilateral landing regardless of the player’s performance level. This could be due to adaptions to sport-specific requirements. Therefore, it is recommended that programs to prevent knee injuries among soccer players consider the dynamics of each leg individually.
      PubDate: 2017-02-13
      DOI: 10.3390/sports5010014
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 15: Between-Session Reliability of Common Strength-
           and Power-Related Measures in Adolescent Athletes

    • Authors: Christopher Thomas, Thomas Dos’Santos, Paul Comfort, Paul Jones
      First page: 15
      Abstract: The purpose of this study was to investigate the between-session reliability of common strength- and power-related measures in adolescent athletes. Seventeen adolescent athletes (males: n = 8: age 17.1 ± 2.2 years; height 175.6 ± 3.5 cm; mass 80.2 ± 3.6 kg; females: n = 9; age 16.9 ± 2.6 years; height 178.5 ± 4.3 cm; mass 71.5 ± 4.5 kg) participated in this study. Isokinetic dynamometry, isometric mid-thigh pull (IMTP), countermovement jump (CMJ), and horizontal jumps (standing broad jump (SBJ) and single-leg hop (SLH)) were each performed twice on separate days, seven days apart. Reliability was assessed by intraclass correlation coefficient (ICC), coefficient of variation (%CV), standard error of measurement (SEM), and smallest detectable difference (SDD). Intraclass correlation coefficients and CV demonstrated acceptable between-session reliability for all measures (ICC > 0.63; CV < 11%), except rate of force development and impulse measures during bilateral and unilateral stance IMTP. Smallest detectable differences demonstrated that changes in performance of >7% CMJ height, >8% SLH distance, >10% in peak isometric force, and >5% in isokinetic peak torques should be considered meaningful, when assessing adolescent athletes.
      PubDate: 2017-02-14
      DOI: 10.3390/sports5010015
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 16: Functional Movement Screen Scores and Physical
           Performance among Youth Elite Soccer Players

    • Authors: Bruno Silva, Filipe Clemente, Miguel Camões, Pedro Bezerra
      First page: 16
      Abstract: This study had two main objectives: (1) to determine if differences in Functional Movement Screen (FMS) scores exist between two levels of competition; and (2) to analyze the association between FMS individual and overall scores and physical performance variables of lower-limb power (jumps), repeated sprint ability and shot speed. Twenty-two Under 16 (U16) and twenty-six Under 19 (U19) national competitive soccer players participated in this study. All participants were evaluated according to anthropometrics, FMS, jump performance, instep kick speed and anaerobic performance. There were no significant differences in the individual FMS scores between competitive levels. There were significant negative correlations between hurdle step (right) and Running-based Anaerobic Sprint Test (RAST) power average ( ρ = −0.293; p = 0.043) and RAST fatigue index (RAST FatIndex) ( ρ = −0.340; p = 0.018). The hurdle step (left) had a significant negative correlation to squat jump (SJ) ( ρ = −0.369; p = 0.012). Rotary stability had a significant negative correlation to RAST fatigue index (Right: ρ = −0.311; p = 0.032. Left: ρ = −0.400; p = 0.005). The results suggest that individual FMS scores may be better discriminants of performance than FMS total score and established minimal association between FMS scores and physical variables. Based on that, FMS may be suitable for the purposes of determining physical function but not for discriminating physical performance.
      PubDate: 2017-02-21
      DOI: 10.3390/sports5010016
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 17: Body Composition Evaluation Issue among Young
           Elite Football Players: DXA Assessment

    • Authors: César Leão, Mário Simões, Bruno Silva, Filipe Clemente, Pedro Bezerra, Miguel Camões
      First page: 17
      Abstract: Accurate assessment of body composition is an important issue among athletes. Different methodologies generate controversial results, leading to a deep uncertainty on individual exercise prescriptions. Thus, this study aims to identify the differences between field methods, such as bioelectrical impedance (BIA) and skinfold assessment, with a clinical method, highly accurate, dual-energy X-ray absorptiometry (DXA), among elite young football players. Thirty-eight male football players with a mean (sd) age of 16.7 (0.87) years, involved in the Portuguese national competition of U16 (n = 13) and U19 (n = 25), were evaluated and objective measures of body composition, muscle strength and football skills were collected by trained specialists. Body composition was assessed using BIA (Tanita BC-418, Tanita Corp., Tokyo, Japan), in agreement with all the evaluation premises. Additionally, all athletes were evaluated using the clinical method DXA (Hologic Inc., Waltham, MA, USA). Among the U19 athletes, three skinfold sites (SKF) were assessed: chest, abdomin and thigh. The Spearman correlation coefficients and the mean difference between methods were calculated. The agreement between both methods was analyzed using Bland-Altman plots. Among the evaluated athletes, lower mean values of body fat % were found using BIA as a method of body composition assessment compared with DXA (12.05 vs. 15.58 for U16; 11.97 vs. 14.16 for U19). Despite the moderate correlation between methods (r = 0.33) to estimate the percentage of total fat, the median of the difference (DXA vs. BIA) was relevant in clinical terms, with 2.90% and 1.47% for U16 and U19 athletes, respectively. Stronger correlations were found between the sum of the SKF and DXA fat estimation (r = 0.68). The Bland-Altman plots showed a clear underestimation in the evaluations using the BIA, namely among athletes with better body composition profiles (8%–12% of fat). Using BIA, an underestimation of body fat assessment was observed among 94.5% of the athletes with less than 12% body fat mass. Among the evaluated athletes, fat mass was underestimated at a median value of 2.21% using BIA in comparison with DXA. The sum of the SKF showed a stronger correlation with the reference method (DXA) (r = 0.68) than BIA.
      PubDate: 2017-02-23
      DOI: 10.3390/sports5010017
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 18: Effect of Ball Weight on Speed, Accuracy, and
           Mechanics in Cricket Fast Bowling

    • Authors: Katharine Wickington, Nicholas Linthorne
      First page: 18
      Abstract: The aims of this study were: (1) to quantify the acute effects of ball weight on ball release speed, accuracy, and mechanics in cricket fast bowling; and (2) to test whether a period of sustained training with underweight and overweight balls is effective in increasing a player’s ball release speed. Ten well-trained adult male cricket players performed maximum-effort deliveries using balls ranging in weight from 46% to 137% of the standard ball weight (156 g). A radar gun, bowling target, and 2D video analysis were used to obtain measures of ball speed, accuracy, and mechanics. The participants were assigned to either an intervention group, who trained with underweight and overweight balls, or to a control group, who trained with standard-weight balls. We found that ball speed decreased at a rate of about 1.1 m/s per 100 g increase in ball weight. Accuracy and bowling mechanics were not adversely affected by changes in ball weight. There was evidence that training with underweight and overweight balls might have produced a practically meaningful increase in bowling speed (>1.5 m/s) in some players without compromising accuracy or increasing their risk of injury through inducing poor bowling mechanics. In cricket fast bowling, a wide range of ball weight might be necessary to produce an effective modified-implement training program.
      PubDate: 2017-02-28
      DOI: 10.3390/sports5010018
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 19: Neck Cooling Improves Table Tennis Performance
           amongst Young National Level Players

    • Authors: Terun Desai, Lindsay Bottoms
      First page: 19
      Abstract: This study aimed to examine the effects of neck cooling on table tennis performance. Eight young, National level, male table tennis players (age 16 ± 2 years, height 1.77 ± 0.08 m, body mass 67.54 ± 10.66 kg) were recruited. Participants attended four testing sessions separated by a week. Session one determined fitness levels, and session two was a familiarisation trial. The final two sessions involved completing the table tennis-specific protocol either with (ICE) or without (CON) neck cooling for 1 min before each exercise period (bout: 80–90 shots), which represented an individual game. The exercise protocol required completing three bouts to represent a match, each simulating a different skill (forehand, backhand, alternate forehand and backhand), against a mechanical ball thrower. Performance was measured by the number of balls hitting two pre-determined targets. Heart rate, ratings of perceived exertion (RPE), and thermal sensation (TS) were measured. Total performance scores (shots on target) were significantly greater during ICE (136 ± 26), compared to CON (120 ± 25; p = 0.006) with a 15 (±12)% improvement. Effects for time (p < 0.05) but not condition (p > 0.05) were found for RPE and all other physiological variables. TS significantly decreased with cooling throughout the protocol (p = 0.03). Neck cooling appears to be beneficial for table tennis performance by lowering thermal sensation.
      PubDate: 2017-03-11
      DOI: 10.3390/sports5010019
      Issue No: Vol. 5, No. 1 (2017)
       
  • Sports, Vol. 5, Pages 20: Detection and Selection of Behavioral Patterns
           Using Theme: A Concrete Example in Grassroots Soccer

    • Authors: Mario Amatria, Daniel Lapresa, Javier Arana, M. Anguera, Gudberg Jonsson
      First page: 20
      Abstract: Observational methodology provides a rigorous yet flexible framework for capturing behaviors over time to allow for the performance of subsequent diachronic analyses of the data captured. Theme is a specialized software program that detects hidden temporal behavioral patterns (T-patterns) within data sets. It is increasingly being used to analyze performance in soccer and other sports. The aim of this study was to show how to select and interpret T-patterns generated by the application of three “quantitative” sort options in Theme and three “qualitative” filters established by the researchers. These will be used to investigate whether 7-a-side (F7) or 8-a-side (F8) soccer is best suited to the learning and skills development needs of 7- and 8-year-old male soccer players. The information contained in the T-patterns generated allowed us to characterize patterns of play in children in this age group. For both formats, we detected technical-tactical behaviors showing that children of this age have difficulty with first-touch actions and controlling the ball after a throw-in. We also found that ball control followed by a pass or a shot at the goal are common in the central corridor of the pitch. Further, depth of play is achieved by ball control, followed by dribbling and a pass or shot. In F8, we saw that depth of play was achieved through ball control, followed by dribbling and passing of one or more opponents leading to a pass or shot. However, in F7, we saw that players succeeded in advancing from their goal area to the rival goal area through a sequence of actions.
      PubDate: 2017-03-13
      DOI: 10.3390/sports5010020
      Issue No: Vol. 5, No. 1 (2017)
       
 
 
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