Sport-specific Conditioning Research Articles

REGULAR LOW-DOSE CAFFEINE SUPPLEMENTATION DURING TRAINING DOES NOT PROVIDE ADDITIONAL BENEFIT TO SUBSEQUENT EXERCISE PERFORMANCE IN AUSTRALIAN RULES FOOTBALL ATHLETES

INTRODUCTION & AIMS Acute caffeine supplementation can improve exercise types like those completed by Australian Rules football (ARF) players during training. Hypothetically athletes could implement caffeine supplementation prior to training, allowing them to complete more training volume, improving adaptation and subsequent exercise performance. This study aimed to investigate the effect of regular low-dose caffeine ingestion pre-training during a training block on subsequent exercise performance. METHODS Twenty-nine male semi-professional ARF players were randomly allocated to a caffeine or placebo group. The four-week intervention period involved participants ingesting 2 mg·kg·BM-1 of caffeine or a placebo 60 min prior to two of their three weekly training sessions, which incorporated sport-specific conditioning and skills training. To assess exercise performance, a battery of tests was used before and after the intervention period including the Yo-Yo Intermittent Recovery Test Level 2 (YYIRT2), 20 m sprint and vertical jump (VJ). Performance differences were assessed using a linear mixed-effect model. RESULTS Mean session rating of perceived exertion (p = .24) and total training load (p =.53) were not different between caffeine and placebo groups over the intervention. There were no significant time x condition interaction effects for YYIRT2 accumulated distance (p = .87), or 5, 10 and 20 m sprint times (p =.06 - .44), however both caffeine and placebo groups improved YYIRT2 distance and sprint times following four weeks of training (p < 0.01). There was a significant effect for time showing decreased VJ performance (p < 0.01), with greater reductions in the placebo group (p = .03). CONCLUSION It is more beneficial to implement an effective training program for athletes rather than focusing effort on regular low-dose caffeine supplementation to augment the training stimulus. The training stimulus itself is typically greater for developing endurance and sprint effort performance, with supplemental caffeine showing no additional performance benefit.

Musculoskeletal Injuries in Elite Collegiate Tenpin Bowling Athletes.

Collegiate tenpin bowling participation is increasing. Accordingly, the experience level of athletes participating, factors related to performance, as well as training workload and sport specialization are likely evolving. However, literature regarding injury rates remains extremely limited. The purpose of this study was to characterize injuries in collegiate tenpin bowlers. Retrospective cohort survey study. Tenpin bowling athletes of top-ranked collegiate programs in the United States were invited to participate. Each participant completed an online survey to report on their injury history and additional factors of interest. Descriptive statistics were generated for participant characteristics, injury counts, and overall injury prevalence and recurrence. Chi-square tests were used to determine if overall injury prevalence and recurrence occurred by chance, and to evaluate the influence of gender and conditioning program participation on injury frequencies. The response rate was 40.6% (101/249; N = 101). The sample was 20.02 (1.43)years old and 54.5% female. There were a total of 235 singular and recurrent injuries reported across all body parts. Upper-extremity injuries were the most common (n = 112). Injury prevalence (87%) and recurrence (75%) were more likely than chance (χ2 > 21.3, both P < .001) and not different based on gender (χ2 ≤ 1.1, both P ≥ .33). Injuries were more frequent in the absence of a conditioning program (χ2 = 50.6, P < .001). Injuries and injury recurrence in elite tenpin bowlers were frequent, most common in the upper-extremity, not different based on gender, and more frequent in those without conditioning programs. Findings may serve as foundational knowledge for developing sport-specific rehabilitation and conditioning programs.

Sport-specific training induced adaptations in postural control and their relationship with athletic performance.

Effects of various exercise programs on postural balance control in athletes and their underlying physiological mechanisms have been extensively investigated. However, little is known regarding how challenging sport-specific conditions contribute to the improvement of body balance and to what extent these changes may be explained by sensorimotor and/or neuromuscular function adaptations. Analysis of the literature could provide useful information on the interpretation of changes in postural sway variables in response to long-term sport-specific training and their association with performance measures. Therefore, the aim of this scoping review was (1) to analyze the literature investigating postural control adaptations induced by sport-specific training and their relationship with measures of athletic performance, and (2) to identify gaps in the existing research and to propose suggestions for future studies. A literature search conducted with Scopus, Web of Science, MEDLINE and Cochrane Library was completed by Elsevier, SpringerLink and Google Scholar with no date restrictions. Overall, 126 articles were eligible for inclusion. However, the association between variables of postural balance control and measures of sport-specific performance was investigated in only 14 of the articles. A relationship between static and/or dynamic balance and criterion measures of athletic performance was revealed in shooting, archery, golf, baseball, ice-hockey, tennis, and snowboarding. This may be ascribed to improved ability of athletes to perform postural adjustments in highly balanced task demands. However, the extent to which sport-specific exercises contribute to their superior postural stability is unknown. Although there is a good deal of evidence supporting neurophysiological adaptations in postural balance control induced by body conditioning exercises, little effort has been made to explain balance adaptations induced by sport-specific exercises and their effects on athletic performance. While an enhancement in athletic performance is often attributed to an improvement of neuromuscular functions induced by sport-specific balance exercises, it can be equally well ascribed to their improvement by general body conditioning exercises. Therefore, the relevant experiments have yet to be conducted to investigate the relative contributions of each of these exercises to improving athletic performance.

Construction of a sport-specific strength and conditioning evaluation index system for elite male wheelchair badminton athletes by the Delphi method

In this study, the Delphi method was used to construct the evaluation index system of the specific physical fitness of Chinese wheelchair badminton players. The Delphi method was used in the first two rounds to determine sport-specific strength and conditioning evaluation indexes for wheelchair badminton athletes. The Analytic Hierarchy Process was used in the third round to determine the weighting of each index. The results indicate that the recovery rate of questionnaires in the first two rounds was higher than 90%, the degree of expert authority was &gt;80%, the degree of expert coordination in the second round was 0.350 and was greater than that in the first round (0.298), and significance testing of the coordination coefficient was significant (p &lt; 0.001), thus indicating that expert opinions were consistent. Results during construction of the evaluation system were credible. Ultimately, we identified four primary indicators, 12 secondary indicators, and 30 tertiary indicators. The order of the four primary indices in terms of weighting was as follows: sport-specific skills (0.4406), sports qualities (0.2928), cardiorespiratory function (0.1828), and body shape (0.0838). We used the Delphi method to construct an evaluation index system for the sport-specific physical ability of elite male wheelchair badminton athletes. The index system exhibited high credibility and specificity for wheelchair badminton.

The Influence of Ballistic Exercises on Growth, Somatomedin Hormones for Soccer Players

BACKGROUND: The sequence of exercise-induced hormonal changes demonstrates the quantification of training and competition loads and developing a sport-specific conditioning program. AIM: The present study investigates the impact of ballistic exercises on biochemical variables and the muscular ability of soccer players. METHODS: Participants were assigned randomly to two groups, including ten participants in each group, and underwent a pre- post-intervention test, including growth hormone, somatomedin hormone, triple jump, and wide jump. RESULTS: The experimental group showed a significant increase in Growth by 43.56%, somatomedin by 6.99%, Triple jumps by 18.65%, and Wide jump by 15.68% compared to the control group. CONCLUSION: In conclusion, ballistic exercises improved growth and somatomedin hormone, triple jump, and wide jump and thus enhancing biochemical variables and muscular ability.

Aerobic endurance test performance among football players in different age and play-positions during COVID-19

Endurance is an ability to withstand against fatigue in sport specific conditions or perform for long period of time. Sport specific endurance in football players is crucial to meet the demand of the sport. Endurance performance represents a very important fitness component to maintain a high level of intensity throughout the game and also in selection and profiling of football players. Covid-19 is highly transmitted viral infection affecting respiratory tract and lungs. Covid-19 restrictions has affected the training pattern of the players. This study is to assess aerobic endurance of football players based on their age and play positions. Total of 67 convenient samples were assessed using the endurance field test (YO-YO Intermittent Recovery test). The results obtained shows that there is significant difference in endurance scorewithin the age group of 16-25 years, with p value of 0.009.Also, there is significant difference in play-positions with p value of 0.000. Hence it is concluded that there is significant difference in aerobic endurance among football players in different age and play-positions.

An Alternative Early Field Experience for Physical Education Teacher Preparation

Implementation of early field experiences is a required component in nearly all teacher education programs because of the first-hand training in real-world situations that complement classroom learning. It is through the experiences that pre-service teachers have the platform to develop and demonstrate their competency in content knowledge, pedagogical skills, and professional dispositions. However, the onset of COVID-19 pandemic made it impossible to set up in-person early field experiences. The purpose of this study was to (a) describe an alternative early field experience planned and implemented to accommodate COVID-19 restrictions, (b) document what the participants learned throughout the experience, and (c) provided university faculty with suggestions for virtual early field experiences. Nineteen students enrolled in a 200-level physical education teacher education activity class in the Spring of 2021 submitted 10 weekly reports after watching self-selected videos that were related to soccer and volleyball. The duration of each video submission was analyzed using descriptive statistics. Data analyzed using the standard interpretive methods revealed three main themes. To identify their content knowledge acquisition, the participants described historical facts, abridged rules and regulations, sport-specific skills, strength and conditioning exercises, and tactical moves and team strategies. They also made game-related observations on the players, teams, and officials. Lastly, entertainment value was highlighted as a result of the freedom to choose the videos they were interested in. Suggestions for incorporating this early field experience and future research directions were discussed.

The Role of Neuromuscular Control of Postural and Core Stability in Functional Movement and Athlete Performance.

Balance and core stabilization exercises have often been associated with improved athlete performance and/or decreased incidence of injuries. While these exercises seem to be efficient in the prevention of injuries, there is insufficient evidence regarding their role in sport-specific performance and related functional movements. The aim of this scoping review is (1) to map the literature that investigates whether currently available variables of postural and core stability are functionally related to athlete performance in sports with high demands on body balance and spinal posture and (2) to identify gaps in the literature and suggest further research on this topic. The literature search conducted on MEDLINE, Scopus, Web of Science, PubMed, and Cochrane Library databases was completed by Google Scholar, SpringerLink, and Elsevier. Altogether 21 articles met the inclusion criteria. Findings revealed that postural stability plays an important role in performance in archery, biathlon, gymnastics, shooting, and team sports (e.g., basketball, hockey, soccer, tennis). Also core stability and strength represent an integral part of athlete performance in sports based on lifting tasks and trunk rotations. Variables of these abilities are associated with performance-related skills in cricket, cycling, running, and team sports (e.g., baseball, football, hockey, netball, soccer, tennis). Better neuromuscular control of postural and core stability contribute to more efficient functional movements specific to particular sports. Training programs incorporating general and sport-specific exercises that involve the use of postural and core muscles showed an improvement of body balance, back muscle strength, and endurance. However, there is controversy about whether the improvement in these abilities is translated into athletic performance. There is still a lack of research investigating the relationship of body balance and stability of the core with sport-specific performance. In particular, corresponding variables should be better specified in relation to functional movements in sports with high demands on postural and core stability. Identifying the relationship of passive, active, and neural mechanisms underlying balance control and spinal posture with athlete performance would provide a basis for a multifaced approach in designing training and testing tools addressing postural and core stability in athletes under sport-specific conditions.

Physiological Mechanisms of Exercise and Its Effects on Postural Sway: Does Sport Make a Difference?

While the effect of a variety of exercises on postural balance control has been extensively studied, less attention has been paid to those requiring sport-specific skills. Therefore there is a need to analyze the literature and elucidate changes in postural balance control after exercises performed in conditions close to a particular sport. This scoping review aims (i) To map the literature that addresses postural sway aspects of acute responses to general and sport-specific exercises and their underlying physiological mechanisms, and (ii) To identify gaps in the existing literature and propose future research on this topic. The main literature search conducted on MEDLINE, Web of Science, Scopus, PubMed, and Cochrane Library databases was completed by SpringerLink, Elsevier, and Google Scholar. A total of 60 articles met the inclusion criteria. Findings identified that among a variety of studies evaluating the effects of exercise on postural balance control, only few of them were conducted under sport-specific conditions (i.e., while shooting in biathlon or pentathlon, and after simulated or match-induced protocols in combat and team sports). Therefore, more research is still needed to address this gap in the literature and aim research at investigation of postural sway response to sport-specific exercises. Further analysis of the literature showed that the type, intensity and duration of exercise play a key role in increased postural sway. Whole body and localized muscular fatigue of the trunk, neck and lower limbs is considered to be a main factor responsible for the magnitude of balance impairment in an initial phase of recovery and speed of its readjustment to a pre-exercise level. Other likely factors affecting postural stability are hyperventilation and deterioration of sensorimotor functions, though some contribution of muscle damage, dehydration, hyperthermia or dizziness cannot be excluded. A better understanding of the physiological mechanisms of balance impairment after exercises performed under simulated fatigue induced protocol, close to conditions specific to a particular sport, has implications for designing smart exercise programs tailored to individual needs to improve athlete performance with high demands on postural stability and/or decrease their risk of injuries.

Strength and Conditioning for the Roller Derby Athlete

ABSTRACT Roller derby's popularity has surged in recent decades. To the best of our knowledge, this is the first strength and conditioning publication to address roller derby. This article outlines an overview of the sport, discusses sport-specific strength and conditioning considerations, and is intended to educate coaches and athletes on the needs of this athletic population. The sport evolved to its current competitive format in 2001 with rules to prevent the theatrics of previous years. The article will present a needs analysis, review current research on relevant-injury prevalence, and outline practical strength and conditioning considerations to enhance performance, reduce injury risk, and increase longevity for roller derby athletes. Finally, the article highlights the need for more sport-specific scientific research to advance roller derby and support its athletes.

Validation of Internal and External Load Metrics in NCAA D1 Women's Beach Volleyball.

Tometz, MJ, Jevas, SA, Esposito, PM, and Annaccone, AR. Validation of internal and external load metrics in NCAA D1 women's beach volleyball. J Strength Cond Res 36(8): 2223-2229, 2022-The purpose of this study was to determine the validity of internal and external load metrics in NCAA D1 women's beach volleyball. Subjects included 13 NCAA D1 women's beach volleyball players (age: 20.3 ± 1.4 years). A total of 578 data points were analyzed from 51 team training sessions, including practice, games, and sport-specific conditioning during the pre-season semester (15 weeks). Data points included Edward's training impulse (TRIMP) (228.0 ± 80.7 arbitrary units [AU]), session rating of perceived exertion (sRPE) Load (532.5 ± 232.8 [AU]), distance covered (DC) in meters (2,635.4 ± 884.3 [m]), and daily environmental condition variables {(temperature (76.5 ± 13.7 [°F]), relative humidity (72.5 ± 13.2 [%]), and wet-bulb globe temperature (52.9 ± 19.9 [°F])}. The subjects wore Polar Team Pro heart rate monitors with global positioning system during each session. Subjects completed an sRPE questionnaire after every session. Pearson product moment correlations yielded statistically significant relationships (p < 0.01) between TRIMP and sRPE Load (r = 0.81), TRIMP and DC (r = 0.78), and sRPE Load and DC (r = 0.82). A forward selection multiple regression yielded that sRPE Load could predict TRIMP with the equation: TRIMPTometz = 78.735 + (sRPE Load * 0.28) (p < 0.001). These findings support sRPE Load as a valid alternative to TRIMP when monitoring internal loads in NCAA D1 women's beach volleyball. Session rating of perceived exertion Load may be more practical and accessible for teams. Distance covered should be considered when periodizing and monitoring training loads because of its relationship with internal loads.

Selected components of physical fitness in rhythmic and artistic youth gymnast

PurposeRhythmic (RG) and artistic gymnastics (AG) are very popular female sports. These two disciplines share some common points but, at the same time, they display some relevant differences in terms of physical and technical characteristics. The aim of this study was as follows: (1) to clarify how gymnastic training background over the years could lead to the development and motor learning of the motor skills and (2) to highlight differences of conditional skills achieved by RG and AG athletes.MethodsFor these aims, 45 athletes were selected, belonging to three balanced groups: promotional (PG, n = 15), RG (n = 15), and AG (n = 15). Participants were tested for joints mobility, balance, explosive strength, speed, and endurance tests.ResultsStatistical analysis showed a good test–retest reliability of the measurements (ICC > 0.870) and some significant differences between PG, RG, and AG. RG showed higher values in joint mobility tests (coxo-femoral mobility, 166.7 ± 6.3°; sit and reach, 20.5 ± 1.9 cm; and scapulo-humeral mobility, 45.5 ± 4.4 cm) with respect to AG, while AG showed higher values in endurance (1626.7 ± 7.4 m), balance (4.33 ± 1.35 n/60 s), and explosive strength (164.1 ± 11.6 cm) compared to RG (p < 0.05).ConclusionRG and AG seem to be effective in enhancing different and sport-specific physical fitness and conditioning. RG enables, indeed, to develop more joints mobility whereas AG improves more strength, balance, and endurance. However, given the small sample size employed, these results should be replicated by further studies utilizing larger samples.

Global Challenges of Being a Strength Athlete during a Pandemic: Impacts and Sports-Specific Training Considerations and Recommendations.

The ongoing global pandemic brought about by Coronavirus II (SARS-Cov-2 or COVID-19) has caused an ongoing cessation of sporting competitions and training facility closures. This is a fundamental challenge for amateur and elite sporting professionals. Although recommendations have been provided for team-sport athletes to maintain general and sport-specific conditioning, these methods are often not optimal for strength athletes (i.e., powerlifting (PL) and weightlifting (WL)) due to the unique and narrow set of performance requirements posed by these sports. The purpose of this review is to provide evidence-based information and recommendations and highlight potential strategies and approaches that may be used by strength (PL and WL) athletes during the current global crisis. Collectively, we provide evidence from resistance training literature regarding the loss of muscle strength, power and mass, minimum training frequencies required to attenuate such losses and training re-adaptation. Additionally, we suggest that time off training and competition caused by ongoing restrictions may be used for other purposes, such as overcoming injury and improving movement quality and/or mobility, goal setting, psychological development and emphasizing strength sports for health. These suggestions are intended to be useful for coaches, strength athletes and organizations where existing training strategies and recommendations are not suitable or no longer feasible.

Effect Of Postural Control And Exertion On Dynamic Visual Acuity In Collegiate Athletes.

Dynamic visual acuity (DVA) requires visuo-perceptual processing to resolve the critical details of a target in motion. Athletes demonstrate superior DVA performance compared to non-athletes in a seated position. PURPOSE: To investigate the effects of different postures and exertion levels on DVA in athletes. METHODS: Varsity rugby players (n=10; female=6; age=20.4yrs ±1.4) without recent concussion (˃ 2 years) and/or vestibular-ocular abnormalities were included. DVA was assessed using a custom program (moV& V&MP, University of Waterloo, Ontario) displayed on a 55” LCD monitor at a viewing distance of 4m. The program presented a randomly (RW) or horizontally (H) moving letter ‘E’ target facing left/right/up/down. Participants had to correctly identify the orientation of the target with a keypad as it progressively reduced in size. DVA was scored as the log of the minimum angle of resolution (LogMAR), of the smallest target correctly identified (i.e., low score = better DVA). Participants completed one RW and H trial at a speed of 2.31m/s (30°/s) during four conditions: seated; standing; and treadmill walking at low (85-100 beats per minute [bpm]) and moderate (115-130bpm) intensities. RESULTS: The difference in LogMAR scores from the seated condition were calculated for each of the other conditions. There were no interaction effects of target motion and posture (F=1.02, p=.382), and no main effect of target motion (F=0.30, p=.598). However, there was a trending main effect of posture (Stand: 0.00 vs. Walk Low: -0.14 vs. Walk Mod: 0.04 p= .056, f= 0.25). These findings indicate that athletes’ DVA improved from seated during moderate intensity treadmill walking more so than both standing and low-intensity treadmill walking. CONCLUSION: Athletes appear to have improved DVA in sport-specific conditions of greater postural and exertional demands. Therefore, sport training experience may enhance visuo-perceptual skills. These findings may inform clinicians to consider the assessment of DVA with progressive, dynamic contexts for rehabilitation, such as for return to sport from concussion.

Incidence and risk factors for race-day jockey falls over fourteen years

ObjectivesTo determine the incidence of, and risk factors for, race-day jockey falls occurring in Thoroughbred flat and jumps (hurdle and steeplechase) racing. DesignRetrospective cohort study. MethodsIncidence rates for race-day jockey falls over 14 racing seasons in New Zealand (n=421,596 race-day starts) were calculated per 1000 rides. Univariable and multivariable analyses of jockey, horse and race level risk factors were conducted with Poisson regression in a generalized linear mixed model. ResultsMost races (97%, n=407,948 race starts) were flat racing with 10 races/race-day, whilst most jumps races were longer and had 2 races/race-day. The rate of jockey falls was higher in steeplechase racing (99.9/1000, 95% CI 92.2–108.4) than hurdle (53.2/1000, 95% CI 48.7–58.3) and flat racing (1.2/1000, 95% CI 1.1–1.3, p<0.001). Experienced athletes (both horse and jockey) had lower IRR. In flat racing, IRR increased linearly with the number of race-day rides by the jockey. In jumps races, IRR increased with a fall in a previous race (IRR 1.5/1000, 95% CI 1.3–1.7, p<0.001). A shorter jumps race distance reduced the IRR of a jockey fall. ConclusionsAthlete experience was associated with risk of jockey falls. The linearity of race ride number with IRR and longer distance in jumps racing, indicated that cognitive or physiological fatigue may play a role in the risk of a race-day fall. This data highlights the role sport-specific conditioning programmes may have on reducing risk.

Analysis of Physical Demands During Youth Soccer Match-Play: Considerations of Sampling Method and Epoch Length

ABSTRACTPurpose: The purpose of this study was to examine the physical match profiles of professional soccer players using 3 and 5 min fixed and rolling averages as well as fixed 1 min averages, with considerations to training prescription. Methods: Twenty-nine professional U23 soccer outfield players competed across 17 competitive matches during the 2017/18 season, equating to a total of 130 separate physical match profiles. Match activities were recorded using global positioning system (GPS) devices with integrated micro-electrical mechanical systems (MEMS), recording total distance (TD), high-speed running (HSR), and metabolic power (MP). For each individual match profile and variable, 1, 3, and 5 min peak, post-peak, and average values were calculated using fixed-time epochs (FIXED) and rolling averages (ROLL). Linear mixed models were employed to examine the differences in the dependent variables as a function of the method of measurement. Results: Results revealed significantly higher peak values, for relative TD, relative HSR and relative MP when employing the ROLL sampling method, in comparison to the FIXED method, for both 3 min and 5 min epoch lengths. Analysis of epoch length revealed significantly higher peak values, across all positions, for relative TD, relative HSR and MP for 1 min epochs, in comparison to 3 min and 5 min epochs. Conclusions: The data offers a novel insight into the appropriate identification of physical demands during youth soccer match-play. Researchers and practitioners should consider the sampling method and epoch length when assessing the physical demands of competitive match-play, as well as when designing and prescribing sport-specific conditioning drills.

The Effects of a Cycling Warm-up Including High-Intensity Heavy-Resistance Conditioning Contractions on Subsequent 4-km Time Trial Performance.

Chorley, A and Lamb, KL. The effects of a cycling warm-up including high-intensity heavy-resistance conditioning contractions on subsequent 4-km time trial performance. J Strength Cond Res 33(1): 57-65, 2019-Previous exercise has been shown to improve subsequent performance through different mechanisms. Sport-specific conditioning contractions can be used to exploit the "post-activation potentiation" (PAP) phenomenon to enhance performance although this has rarely been investigated in short endurance events. The aim of this study was to compare a cycling warm-up with PAP-inducing conditioning contractions (CW) with a moderate-intensity warm-up (MW) on performance and physiological outcomes of a 4-km time trial. Ten well-trained male endurance cyclists ((Equation is included in full-text article.)max 65.3 ± 5.6 ml·kg·min) performed two 4-km cycling time trials after a 5-minute recovery after a warm-up at 60% of (Equation is included in full-text article.)max for 6.5 minutes (MW), and a warm-up with conditioning contractions (CW) consisting of 5 minutes at 60% of (Equation is included in full-text article.)max then 3 × 10-second at 70% of peak power interspersed with a 30-second recovery. Blood lactate concentrations were measured before and after time trial. Expired gases were analyzed along with time, power output (PO), and peak forces over each 500 m split. After CW, mean completion time was reduced (1.7 ± 3.5 seconds p > 0.05), PO increased (5.1 ± 10.5 W p > 0.05) as did peak force per pedal stroke (5.7 ± 11 N p > 0.05) when compared with MW. (Equation is included in full-text article.)increased (1.4 ± 1.6 ml·kg·min p ≤ 0.05) after CW, whereas respiratory exchange ratio (RER) decreased (0.05 ± 0.02 p ≤ 0.05). Physiological and performance differences after CW were greatest over the first 1,500 m of the trials. The results suggest that a PAP-inducing warm-up alters (Equation is included in full-text article.)kinetics and can lead to performance improvements in short endurance cycling but work and recovery durations should be optimized for each athlete.

Training history constrains postural sway dynamics: A study of balance in collegiate ice hockey players

BackgroundBalance and postural control are integral to training and sport performance. Demands on posture are contextual and vary in different ways depending on the specific physical activity. Research questionThe purpose of this study was to examine the possibility that sustained exposure to environmental constraints, through specific sport participation, might lead to a persistent modification of postural control. MethodsDouble and single-leg postural sway were compared between ice hockey players, American football players and physically active college students. Data from 30 s trials were analyzed using traditional postural sway measures of range and pathlength of the center of pressure, as well as with Sample Entropy (SEn), in both mediolateral (ML) and anteroposterior (AP) directions. ResultsEach group displayed unique postural sway characteristics. During single-leg stance, ice hockey players show significantly different ML pathlength and ML and AP SEn from the physically active college students (all p < 0.05), and significantly different ML and AP pathlength and AP SEn from the American football players (all p < 0.05). The American football players and the physically active college students differed for all single-legged conditions (all p < 0.05). SignificanceThis suggests that the organization and development of postural sway is not only context dependent but also influenced by training history; supporting the idea that balance training for sport should be designed with regards to sport specific conditions.

Sport-Specific Assessment of the Effectiveness of Neuromuscular Training in Young Athletes.

Neuromuscular training in young athletes improves performance and decreases the risk of injuries during sports activities. These effects are primarily ascribed to the enhancement of muscle strength and power but also balance, speed and agility. However, most studies have failed to demonstrate significant improvement in these abilities. This is probably due to the fact that traditional tests do not reflect training methods (e.g., plyometric training vs. isometric or isokinetic strength testing, dynamic balance training vs. static balance testing). The protocols utilized in laboratories only partially fulfill the current needs for testing under sport-specific conditions. Moreover, laboratory testing usually requires skilled staff and a well equipped and costly infrastructure. Nevertheless, experience demonstrates that high-technology and expensive testing is not the only way to proceed. A number of physical fitness field tests are available today. However, the low reliability and limited number of parameters retrieved from simple equipment used also limit their application in competitive sports. Thus, there is a need to develop and validate a functional assessment platform based on portable computerized systems. Variables obtained should be directly linked to specific features of particular sports and capture their complexity. This is essential for revealing weak and strong components of athlete performance and design of individually-tailored exercise programs. Therefore, identifying the drawbacks associated with the assessment of athlete performance under sport-specific conditions would provide a basis for the formation of an innovative approach to their long-term systematic testing. This study aims (i) to review the testing methods used for the evaluation of the effect of neuromuscular training on sport-specific performance in young athletes, (ii) to introduce stages within the Sport Longlife Diagnostic Model, and (iii) to propose future research in this topic. Analysis of the literature identified gaps in the current standard testing methods in terms of their low sensitivity in discriminating between athletes of varied ages and performance levels, insufficent tailoring to athlete performance level and individual needs, a lack of specificity to the requirements of particular sports and also in revealing the effect of training. In order to partly fill in these gaps, the Sport Longlife Diagnostic Model was proposed.

Criterion-Validity of Commercially Available Physical Activity Tracker to Estimate Step Count, Covered Distance and Energy Expenditure during Sports Conditions.

Background: In the past years, there was an increasing development of physical activity tracker (Wearables). For recreational people, testing of these devices under walking or light jogging conditions might be sufficient. For (elite) athletes, however, scientific trustworthiness needs to be given for a broad spectrum of velocities or even fast changes in velocities reflecting the demands of the sport. Therefore, the aim was to evaluate the validity of eleven Wearables for monitoring step count, covered distance and energy expenditure (EE) under laboratory conditions with different constant and varying velocities.Methods: Twenty healthy sport students (10 men, 10 women) performed a running protocol consisting of four 5 min stages of different constant velocities (4.3; 7.2; 10.1; 13.0 km·h−1), a 5 min period of intermittent velocity, and a 2.4 km outdoor run (10.1 km·h−1) while wearing eleven different Wearables (Bodymedia Sensewear, Beurer AS 80, Polar Loop, Garmin Vivofit, Garmin Vivosmart, Garmin Vivoactive, Garmin Forerunner 920XT, Fitbit Charge, Fitbit Charge HR, Xaomi MiBand, Withings Pulse Ox). Step count, covered distance, and EE were evaluated by comparing each Wearable with a criterion method (Optogait system and manual counting for step count, treadmill for covered distance and indirect calorimetry for EE).Results: All Wearables, except Bodymedia Sensewear, Polar Loop, and Beurer AS80, revealed good validity (small MAPE, good ICC) for all constant and varying velocities for monitoring step count. For covered distance, all Wearables showed a very low ICC (<0.1) and high MAPE (up to 50%), revealing no good validity. The measurement of EE was acceptable for the Garmin, Fitbit and Withings Wearables (small to moderate MAPE), while Bodymedia Sensewear, Polar Loop, and Beurer AS80 showed a high MAPE up to 56% for all test conditions.Conclusion: In our study, most Wearables provide an acceptable level of validity for step counts at different constant and intermittent running velocities reflecting sports conditions. However, the covered distance, as well as the EE could not be assessed validly with the investigated Wearables. Consequently, covered distance and EE should not be monitored with the presented Wearables, in sport specific conditions.