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1.
Exp Brain Res ; 242(8): 1933-1946, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38900160

RESUMO

Visuospatial attention (VSA) is a cognitive function that enables athletes, particularly those engaged in open-skill sports, to allocate attentional resources efficiently to the appropriate target and in the appropriate direction. Studies have indicated that expert players exhibit superior cognitive performance to that of novices. However, no study has investigated differences in VSA performance among elite, expert, and intermediate badminton players or the potential neurophysiological mechanisms underlying such differences. Accordingly, the present study explored neuropsychological and neurophysiological parameters during VSA tasks among badminton players of varying competitive levels. The study included 54 participants and divided them into three groups according to their competition records: elite (n = 18), expert (n = 18), and intermediate (n = 18). Their neuropsychological performance and brain event-related potentials (ERPs) during the Posner cueing paradigm were collected. Although the three groups did not differ in their accuracy rates, ERP N2 amplitudes, or N2 or P3 latencies, the elite and expert groups exhibited notably faster reaction times and more pronounced P3 amplitudes than did the intermediate group during the cognitive task. However, we did not observe these between-group differences when we controlled for the covariate training years. Additionally, the elite and expert groups exhibited comparable neurocognitive performance. These findings indicate that badminton players' competitive levels influence their VSA. However, the beneficial effects on neuropsychological and neurophysiological performance could stabilize after a certain level of badminton competence is reached. Year of training could also be a major factor influencing badminton players' neurocognitive performance in VSA tasks.


Assuntos
Atenção , Eletroencefalografia , Potenciais Evocados , Esportes com Raquete , Percepção Espacial , Humanos , Atenção/fisiologia , Masculino , Esportes com Raquete/fisiologia , Adulto Jovem , Potenciais Evocados/fisiologia , Percepção Espacial/fisiologia , Adulto , Feminino , Percepção Visual/fisiologia , Tempo de Reação/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Comportamento Competitivo/fisiologia , Desempenho Atlético/fisiologia
2.
J Aging Phys Act ; 32(5): 606-623, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710485

RESUMO

BACKGROUND/OBJECTIVES: Engagement in sport offers the potential for improved physical and psychological well-being and has been shown to be beneficial for promoting healthy aging. Opportunities for older adults to (re)engage with sport are limited by a paucity of age-appropriate introductory sports intervention programs. As such, the study evaluated the efficacy of a newly designed 8-week badminton training program (Shuttle Time for Seniors) on markers of healthy aging and the lived experiences of participation. METHODS: Forty-three older adults assigned to a control (N = 20) or intervention group (N = 23) completed pre-post assessment of physical and cognitive function, self-efficacy for exercise, and well-being. Focus groups were conducted for program evaluation and to understand barriers and enablers to sustained participation. RESULTS: Those in the intervention group increased upper body strength, aerobic fitness, coincidence anticipation time, and self-efficacy for exercise. Objectively improved physical and cognitive functions were corroborated by perceived benefits indicated in thematic analysis. Shuttle Time for Seniors was perceived as appropriate for the population, where the age-appropriate opportunity to participate with likeminded people of similar ability was a primary motivator to engagement. Despite willingness to continue playing, lack of badminton infrastructure was a primary barrier to continued engagement. CONCLUSION: Shuttle Time for Seniors offered an important opportunity for older adults to (re)engage with badminton, where the physical and psychosocial benefits of group-based badminton improved facets important to healthy aging. Significance/Implications: Age-appropriate introductory intervention programs provide opportunity for older adults to (re)engage with sport. However, important barriers to long-term engagement need to be addressed from a whole systems perspective.


Assuntos
Envelhecimento Saudável , Esportes com Raquete , Autoeficácia , Humanos , Idoso , Masculino , Feminino , Envelhecimento Saudável/psicologia , Envelhecimento Saudável/fisiologia , Esportes com Raquete/fisiologia , Cognição/fisiologia , Aptidão Física/fisiologia , Grupos Focais , Exercício Físico/psicologia , Força Muscular/fisiologia , Idoso de 80 Anos ou mais
3.
J Strength Cond Res ; 38(9): 1651-1657, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39074193

RESUMO

ABSTRACT: Sutton, PJ, Mumford, PW, and Sunderland, KL. Workloads in collegiate women's lacrosse athletes during a Division II national championship season. J Strength Cond Res 38(9): 1651-1657, 2024-A comprehensive examination of the external and internal workloads in collegiate women's lacrosse athletes has yet to be reported. Thus, the primary purpose of this study was to determine the absolute and relative external and internal training and game workloads of National Collegiate Athletic Association (NCAA) Division II women's lacrosse athletes throughout an entire season. Data from 19 Division II women's lacrosse athletes were analyzed, encompassing each training session and game across an entire competitive season (February-May). External workloads were assessed using a wearable global positioning system, whereas internal workloads were determined through heart rate (HR) variables and session rating of perceived exertion. Game days were associated with significantly ( p < 0.05) greater absolute external and internal workloads. However, when comparing workloads relative to session duration, relative workloads between training and games were no longer significant ( p > 0.05) for total distance, high-speed running (≥15 km·h -1 ), HR-derived training impulse, or caloric expenditure. Nonetheless, relative sprint distance (>19 km·h -1 ) was significantly lower during games, whereas high-intensity accelerations (>2 m·s -2 ) and decelerations (<-2 m·s -2 ) were significantly greater during training compared with games ( p < 0.05). Practical applications of these findings suggest that coaches can better prepare athletes for game day conditions by adjusting training plans to replicate the duration and intensity of games. Overall, this comprehensive examination of internal and external workloads provides valuable data for coaches and practitioners to support performance comparisons, rehabilitation protocols, and workload analyses in collegiate women's lacrosse athletes.


Assuntos
Desempenho Atlético , Frequência Cardíaca , Esportes com Raquete , Corrida , Humanos , Feminino , Adulto Jovem , Esportes com Raquete/fisiologia , Desempenho Atlético/fisiologia , Frequência Cardíaca/fisiologia , Corrida/fisiologia , Condicionamento Físico Humano/fisiologia , Condicionamento Físico Humano/métodos , Atletas , Esforço Físico/fisiologia , Sistemas de Informação Geográfica , Comportamento Competitivo/fisiologia , Universidades
4.
J Sports Sci ; 41(10): 972-989, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37742342

RESUMO

Badminton footwork has been characterised with jump-landing, cross step, side side and lunges, which requires movement agility to facilitate on-court performance. A novel badminton shoe design with systematic increase of lateral wedge hardness (Asker C value of 55, 60, 65, and 70) was developed and investigated in this study, aiming to analyse the dose-response effect of incremental wedge hardness on typical badminton footwork. Stance time and joint stiffness were employed to investigate the footwork performance, and the factorial Statistical non-Parametric Mapping and Principal Component Analysis (PCA) were used to quantify the biomechanical responses over the stance. As reported, shorter contact times (decreased by 8.9%-13.5%) and increased joint stiffness (in side step) of foot-ankle complex were found, suggesting improved footwork stability and agility from increased hardness. Time-varying differences were noted during the initial landing and driving-off phase of cross and side steps and drive-off returning of lunges, suggesting facilitated footwork performance. The reconstructed modes of variations from PCA further deciphered the biomechanical response to the wedge dosage, especially during drive-off, to understand the improved footwork agility and stability.


Assuntos
Extremidade Inferior , Esportes com Raquete , Humanos , Fenômenos Biomecânicos/fisiologia , Dureza , Extremidade Inferior/fisiologia , Articulações/fisiologia , Esportes com Raquete/fisiologia
5.
J Aging Phys Act ; 31(3): 365-370, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36087934

RESUMO

The purpose of this study was to measure heart rate, activity intensity, and steps in recreational singles and doubles pickleball players. We collected data in 22 singles and 31 doubles players (62.1 ± 9.7 years of age) using Garmin Fenix 5 watches (Garmin International, Inc.) and ActiGraph GT3X+ (ActiGraph LLC) accelerometers. Mean heart rates during singles and doubles were 111.6 ± 13.5 and 111.5 ± 16.2 beats/min (70.3% and 71.2% of predicted maximum heart rate), respectively. Over 70% of singles and doubles playing time was categorized in moderate to vigorous heart rate zones whereas 80.5% of singles time and 50.4% of doubles time were moderate based on Freedson accelerometer cut-points. Steps per hour were higher in singles versus doubles (3,322 ± 493 vs. 2,791 ± 359), t(51) = 4.540, p < .001. Singles and doubles pickleball are moderate- to vigorous-intensity activities that can contribute substantially toward older adults meeting physical activity guidelines.


Assuntos
Exercício Físico , Esportes com Raquete , Idoso , Humanos , Exercício Físico/fisiologia , Pessoa de Meia-Idade , Esportes com Raquete/fisiologia , Frequência Cardíaca
6.
Sensors (Basel) ; 22(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408199

RESUMO

This study quantified the strength of the relationship between the percentage of heart rate reserve (%HRR) and two acceleration-based intensity metrics (AIMs) at three sensor-positions during three sport types (running, basketball, and badminton) under three intensity conditions (locomotion speeds). Fourteen participants (age: 24.9 ± 2.4 years) wore a chest strap HR monitor and placed three accelerometers at the left wrist (non-dominant), trunk, and right shank, respectively. The %HRR and two different AIMs (Player Load per minute [PL/min] and mean amplitude deviation [MAD]) during exercise were calculated. During running, both AIMs at the shank and PL at the wrist had strong correlations (r = 0.777-0.778) with %HRR; while other combinations were negligible to moderate (r = 0.065-0.451). For basketball, both AIMs at the shank had stronger correlations (r = 0.604-0.628) with %HRR than at wrist (r = 0.536-0.603) and trunk (r = 0.403-0.463) with %HRR. During badminton exercise, both AIMs at shank had stronger correlations (r = 0.782-0.793) with %HRR than those at wrist (r = 0.587-0.621) and MAD at trunk (r = 0.608) and trunk (r = 0.314). Wearing the sensor on the shank is an ideal position for both AIMs to monitor external intensity in running, basketball, and badminton, while the wrist and using PL-derived AIM seems to be the second ideal combination.


Assuntos
Esportes com Raquete , Corrida , Aceleração , Adulto , Benchmarking , Exercício Físico , Frequência Cardíaca , Humanos , Esportes com Raquete/fisiologia , Corrida/fisiologia , Adulto Jovem
7.
J Sports Sci Med ; 21(1): 82-90, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35250337

RESUMO

The physiological and performance attributes of elite squash players were investigated. Thirty-one players (21 males, world ranking [WR] 42-594; 10 females, WR 7-182) completed a battery of fitness tests which included an aerobic squash-specific physical performance test (SPPT), repeated-sprint ability (RSA), change-of-direction speed (COD), acceleration (5-m sprint), body composition and force development (countermovement jump) assessments. The SPPT provided a finishing lap score, V̇O2max, average movement economy and the lap corresponding to a blood lactate concentration of 4 mM.L-1. Players were ranked and assigned to HIGH or LOW performance tiers. Two-way ANOVA (performance level*sex) revealed higher ranked players performed better (p < 0.05) for SPPT final lap (d = 0.35), 4 mM.L-1 lap (d = 0.52) and COD (d = 0.60). SPPT displayed a 'very-large' correlation with 4 mM.L-1 lap (r = 0.86), 'large' correlations with COD (r = 0.79), RSA (r = 0.79), sum-of-7 skinfolds (r = 0.71) and V̇O2max (r = 0.69), and a 'trivial' correlation with average movement economy (r = 0.02). Assessments of cardiovascular fitness (i.e. 4 mM.L-1 lap), RSA, COD and body composition appear highly pertinent for performance profiling of squash players. Regular, submaximal assessment of the 4 mM.L-1 lap during the SPPT may offer a practical athlete monitoring approach for elite squash players.


Assuntos
Desempenho Atlético , Esportes com Raquete , Desempenho Atlético/fisiologia , Exercício Físico , Teste de Esforço , Feminino , Humanos , Masculino , Desempenho Físico Funcional , Esportes com Raquete/fisiologia
8.
J Sports Sci ; 39(9): 1070-1076, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33393411

RESUMO

This study examined the relationship between pre-training wellness scores and internal and external training load outputs during the preparation phase of a Division I women's collegiate lacrosse team. Athletes (n = 27) logged daily wellness (sleep, energy, stress, and how their muscles felt), session ratings of perceived exertion, and training metrics for 13 weeks. Load metrics were collected with microtechnology units. Repeated measures mixed linear models were constructed to evaluate the relationships between wellness and training load. The largest effects observed indicated: improved sleep was predictive of increased total distance (by as much as 310.5 m, 95%CI 36.7-584.3), high-intensity distance (by as much as 72.7 m, 95%CI 17.2-128.3), and Athlete Load (by as much as 6.8AU, 95%CI 1.8-11.8); more energy was predictive of increased total distance (by as much as 323.6 m, 95%CI 52.2-594.9) and Athlete Load (by as much as 5.6AU. 95%CI 0.6-10.5). For each one-unit increase in overall wellness score, total distance (3.5 m, 95%CI 1.2-15.1) and Athlete Load (0.2AU, 95%CI 0.0-0.3) increased. Pre-training wellness scores and sub-scores are predictive of external load training output. Monitoring athlete wellness systematically can help coaches with decision-making relevant to training and game performance.


Assuntos
Desempenho Atlético/fisiologia , Condicionamento Físico Humano/fisiologia , Esforço Físico/fisiologia , Esportes com Raquete/fisiologia , Sono/fisiologia , Tomada de Decisões , Feminino , Humanos , Modelos Lineares , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Estresse Fisiológico/fisiologia , Adulto Jovem
9.
J Strength Cond Res ; 35(11): 3207-3212, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31343545

RESUMO

ABSTRACT: Hauer, R, Tessitore, A, Hauer, K, and Tschan, H. Activity profile of international female lacrosse players. J Strength Cond Res 35(11): 3207-3212, 2021-This study was designed to investigate the activity profile in international women's lacrosse match-play. Data were collected of 10 female Austrian lacrosse national team players (29.1 ± 6.1 years; 64.2 ± 5.0 kg; and 165.3 ± 4.1 cm) during 4 games of an international tournament using global positioning system and heart rate monitor devices. The mean average heart rate was 75.3 ± 5.0% of maximum heart rate (HRmax) with 23 ± 6.1% of total playing time spent in HRzone 4 (80-90% of HRmax). The mean distance covered during match-play was 3,791.6 ± 554.5 m, of which 38 ± 6.5% were performed in speed zone 1 (<7.0 km·h-1). Ten ±4 sprints per game were conducted with 55 ± 3.8% of accelerations and 59 ± 3.1% of decelerations in zone 1, respectively. Defenders showed greater total distance covered compared with other positions (attack: p = 0.035; d = 0.87; confidence interval [CI] = 0.18-1.56 and midfield: p = 0.006; d = 1.66; CI = 0.93-2.40). Midfielders covered less distance in speed zone 1 (p = 0.032; d = 1.91; CI = 0.53-3.28) compared with attackers, and lower numbers of accelerations (p = 0.042; d = 0.96; CI = 0.20-1.72) and decelerations (p = 0.021; d = 1.79; CI = 0.61-2.97) in zone 3 compared with defenders. Furthermore, attackers showed less distance covered in speed zone 1 (p = 0.09; d = 1.62; CI = 0.86-2.38) compared with defenders. The provided activity data could help coaches and practitioners in designing competition-specific programs for athletes. In addition, positional differences should be taken into account for tactical and physiological aspects.


Assuntos
Desempenho Atlético , Esportes com Raquete , Corrida , Aceleração , Desempenho Atlético/fisiologia , Feminino , Sistemas de Informação Geográfica , Humanos , Esportes com Raquete/fisiologia , Corrida/fisiologia
10.
J Sport Rehabil ; 30(5): 717-724, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33465761

RESUMO

CONTEXT: Badminton continues to be a highly competitive sport where training is introduced at an early age and load has intensified. This exposes players to a greater risk of injuries, in particular when assessing related training outcomes such as strength, agonist-antagonist ratio, and bilateral deficit among adolescents where age- and sex-associated growth and development should be considered. OBJECTIVE: To evaluate strength profile of the upper and lower limbs among adolescent elite Malaysian badminton players. DESIGN: Cross-sectional study. SETTING: Laboratory. PARTICIPANTS: Forty-eight asymptomatic athletes (24 males and 24 females) were grouped into early and late adolescence (13-14 y old and 15-17 y old, respectively). MAIN OUTCOME MEASURE(S): Strength (absolute and normalized) of the external/internal rotators of the shoulder and flexor/extensor of the knee and strength derivatives, conventional strength ratio (CSR), dynamic control ratio (DCR), and bilateral deficits were measured. RESULTS: Males showed greater strength in all strength indices (P < .05). The older group had greater strength compared to younger for most of the upper and lower limb indices (P < .05); these effects diminished when using normalized data. For females, there was no age group effect in the shoulder and knee strength. All players displayed lower shoulder and knee normative values for CSR and DCR. Dominant and non-dominant knee strength were comparable between sex and age groups. CONCLUSIONS: For males, growth and maturation had a greater contribution to strength gained compared to training, whereas for females, growth, maturation, and training did not improve strength. The normalized data indicated that training did not improve all indices measured apart from external rotator strength in females. All players also displayed lower normative values of CSR and DCR. These results suggest that training in elite adolescent Malaysian badminton players lacks consideration of strength gain and injury risk factors.


Assuntos
Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Esportes com Raquete/fisiologia , Articulação do Ombro/fisiologia , Adolescente , Desenvolvimento do Adolescente/fisiologia , Fatores Etários , Atletas , Estudos Transversais , Feminino , Lateralidade Funcional/fisiologia , Humanos , Malásia , Masculino , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/fisiologia , Manguito Rotador/fisiologia , Fatores Sexuais , Torque
11.
Res Sports Med ; 29(4): 386-394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33870819

RESUMO

High-speed running density (HSRd) is the ratio of high-speed efforts and distance covered. This study aimed to evaluate differences in HSRd between training, games, and among positions in collegiate women's lacrosse, and correlate HSRd with other training metrics. Data were collected during a collegiate training year (practices n = 162, games n = 14) through players (n = 25) wearing microtechnology. HSRd differed between training sessions and games (p < .001, d = .281) and by position (p < .001, d = .005-.712). Games (14.7 ± 13.8%) had a higher HSRd than training sessions (13.1 ± 13.7%), and goalies had higher HSRd during games than the other positions. HSRd was moderately inversely correlated (p < .001) with max speed (r = -.395-.543) and had low inverse correlations (p < .001) with distance (r = -.134-.225), accelerations (r = -217-.233), and decelerations (r = -.195-.268). Training did not mimic the HSRd of games. Defenders and goalies perform intense reactionary movements to make a defensive play, resulting in higher HSRd.


Assuntos
Desempenho Atlético/fisiologia , Esportes com Raquete/fisiologia , Corrida/fisiologia , Adolescente , Adulto , Feminino , Sistemas de Informação Geográfica , Humanos , Estudos Prospectivos , Universidades , Adulto Jovem
12.
J Sports Sci Med ; 20(1): 101-109, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33707993

RESUMO

This study investigated the relationships between internal and external training load metrics across a 2-week 'in-season' microcycle in squash. 134 on-court and 32 off-court 'conditioning' sessions were completed by fifteen elite squash players with an average (±SD) of 11 ± 3 per player. During every session, external load was captured using a tri-axial accelerometer to calculate Playerload; i.e., the instantaneous rate of change of acceleration across 3-dimensional planes. Internal load was measured using heart rate (HR), global (sRPE) and differential RPE (dRPE-Legs, dRPE-Breathing). Additionally, HR was used to calculate Banister's, Edward's and TEAM TRIMPs. Across 166 training sessions, Playerload was moderately correlated with TRIMP-Banister (r = 0.43 [95% CI: 0.29-0.55], p < 0.001) and TRIMP-Edwards (r = 0.50 [0.37-0.61], p < 0.001). Association of Playerload with TRIMP-TEAM (r = 0.24 [0.09-0.38], p = 0.001) was small. There was a moderate correlation between sRPE and Playerload (r = 0.46 [0.33-0.57], p < 0.001). Association of sRPE was large with TRIMP-Banister (r = 0.68 [0.59-0.76], p = 0.001), very large with TRIMP-Edwards (r = 0.79 [0.72-0.84], p < 0.001) and moderate with TRIMP-TEAM (r = 0.44 [0.31-0.56], p < 0.001). Both dRPE-Legs (r = 0.95 [0.93-0.96], p < 0.001) and dRPE-Breathing (r = 0.92 [0.89-0.94], p < 0.001) demonstrated nearly perfect correlations with sRPE and with each other (r = 0.91 [0.88-0.93], p < 0.001). Collection of both internal and external training load data is recommended to fully appreciate the physical demands of squash training. During a training microcycle containing a variety of training sessions, interpreting internal or external metrics in isolation may underestimate or overestimate the training stress a player is experiencing.


Assuntos
Atletas , Frequência Cardíaca/fisiologia , Condicionamento Físico Humano/métodos , Esportes com Raquete/fisiologia , Taxa Respiratória/fisiologia , Aceleração , Acelerometria , Desaceleração , Feminino , Humanos , Malásia , Masculino , Monitorização Fisiológica/métodos , Movimento/fisiologia , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/fisiologia , Fatores de Tempo , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
13.
J Sports Sci ; 38(21): 2471-2478, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32662349

RESUMO

A logarithmic curve fitting methodology for the calculation of badminton racket-shuttlecock impact locations from three-dimensional motion capture data was presented and validated. Median absolute differences between calculated and measured impact locations were 3.6 [IQR: 4.4] and 3.5 [IQR: 3.5] mm mediolaterally and longitudinally on the racket face, respectively. Three-dimensional kinematic data of racket and shuttlecock were recorded for 2386 smashes performed by 65 international badminton players, with racket-shuttlecock impact location assessed against instantaneous post-impact shuttlecock speed and direction. Mediolateral and longitudinal impact locations explained 26.2% (quadratic regression; 95% credible interval: 23.1%, 29.2%; BF10 = 1.3 × 10131, extreme; p < 0.001) of the variation in participant-specific shuttlecock speed. A meaningful (BF10 = ∞, extreme; p < 0.001) linear relationship was observed between mediolateral impact location and shuttlecock horizontal direction relative to a line normal to the racket face at impact. Impact locations within one standard deviation of the pooled mean impact location predict reductions in post-impact shuttlecock speeds of up to 5.3% of the player's maximal speed and deviations in the horizontal direction of up to 2.9° relative to a line normal to the racket face. These results highlight the margin for error available to elite badminton players during the smash.


Assuntos
Desempenho Atlético/fisiologia , Destreza Motora/fisiologia , Esportes com Raquete/fisiologia , Fenômenos Biomecânicos , Humanos , Movimento , Equipamentos Esportivos , Estudos de Tempo e Movimento
14.
J Sports Sci ; 38(13): 1560-1565, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32238017

RESUMO

Ankle sprains are the most common injury in regular badminton players and usually occur at the end of a match or training. The purpose of the present study was to examine the influence of fatigue produced by badminton practice on the lower limb biomechanics of badminton players. It was hypothesized that fatigue induces ankle kinematic and lower leg muscle activity changes which may increase the risk of ankle sprain. Ankle kinematics, ankle kinetics and muscles activities of 17 regular badminton players were recorded during lateral jumps before and after an intense badminton practice session. Post-fatigue, ankle inversion at foot strike and peak ankle inversion increased (+2.6°, p = 0.003 and +2.5°, p = 0.005, respectively). EMG pre-activation within 100 ms before foot landing significantly decreased after fatigue for soleus (-23.4%, p = 0.031), gastrocnemius lateralis (-12.2%, p = 0.035), gastrocnemius medialis (-23.3%, p = 0.047) and peroneus brevis (-17.4%, p = 0.036). These results demonstrate impaired biomechanics of badminton players when fatigue increases, which may cause a greater risk of experiencing an ankle sprain injury.


Assuntos
Traumatismos do Tornozelo/fisiopatologia , Extremidade Inferior/fisiologia , Esportes com Raquete/lesões , Esportes com Raquete/fisiologia , Entorses e Distensões/fisiopatologia , Adulto , Fenômenos Biomecânicos , Eletromiografia , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto Jovem
15.
J Sports Sci ; 38(13): 1550-1559, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32292100

RESUMO

Knowledge of the kinematic differences that separate highly skilled and less-skilled squash players could assist the progression of talent development. This study compared trunk, upper-limb and racket kinematics between two groups of nine highly skilled and less-skilled male athletes for forehand drive, volley and drop strokes. A 15-camera motion analysis system recorded three-dimensional trajectories, with five shots analysed per participant per stroke. The highly skilled group had significantly (p < 0.05) larger forearm pronation/supination range-of-motion and wrist extension angles at impact than the less-skilled. The less-skilled group had a significantly more "open" racket face and slower racket velocities at impact than the highly skilled. Rates of shoulder internal rotation, forearm pronation, elbow extension and wrist flexion at impact were greater in the drive stroke than in the other strokes. The position of the racket at impact in the volley was significantly more anterior to the shoulder than in the other strokes, with a smaller trunk rotation angular velocity. Players used less shoulder internal/external rotation, forearm pronation/supination, elbow and wrist flexion/extension ranges-of-motions and angular velocities at impact in the drop stroke than in the other strokes. These findings provide useful insights into the technical differences that separate highly skilled from less-skilled players and provide a kinematic distinction between stroke types.


Assuntos
Destreza Motora/fisiologia , Esportes com Raquete/fisiologia , Tronco/fisiologia , Extremidade Superior/fisiologia , Adolescente , Fenômenos Biomecânicos , Cotovelo/fisiologia , Antebraço/fisiologia , Humanos , Masculino , Amplitude de Movimento Articular , Rotação , Ombro/fisiologia , Estudos de Tempo e Movimento , Punho/fisiologia , Adulto Jovem
16.
J Sports Sci ; 38(10): 1115-1123, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32223529

RESUMO

To maintain the accuracy of squash shots under varying conditions, such as the oncoming ball's velocity and trajectory, players must adjust their technique. Although differences in technique between skilled and less-skilled players have been studied, it is not yet understood how players vary their technique in a functional manner to maintain accuracy under varying conditions. This study compared 3-dimensional joint and racket kinematics and their variability between accurate and inaccurate squash forehand drives of 9 highly skilled and 9 less-skilled male athletes. During inaccurate shots, less-skilled players hit the ball with a more open racket, demonstrating a difference in this task-relevant parameter. No joint kinematic differences were found for accuracy for either group. Coordinated joint rotations at the elbow and wrist both displayed a "zeroing-in" effect, whereby movement variability was reduced from the initiation of propulsive joint rotation to a higher consistency at ball-impact; potentially highlighting the "functionality" of the variability prior to the impact that enabled consistent task-relevant parameters (racket orientation and velocity) under varying conditions. Further, highly skilled players demonstrated greater consistency of task-relevant parameters at impact than less-skilled players. These findings highlight the superior ability of highly skilled players to adjust their technique to achieve consistent task-relevant parameters and a successful shot.


Assuntos
Destreza Motora/fisiologia , Esportes com Raquete/fisiologia , Tronco/fisiologia , Extremidade Superior/fisiologia , Adulto , Fenômenos Biomecânicos , Cotovelo/fisiologia , Antebraço/fisiologia , Humanos , Masculino , Rotação , Ombro/fisiologia , Estudos de Tempo e Movimento , Punho/fisiologia , Adulto Jovem
17.
J Sports Sci ; 38(17): 1943-1952, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32546052

RESUMO

This study aimed to assess which combination of subjective and empirical data might help to identify the expertise level. A group of 10 expert coaches classified 40 participants in 5 different expertise groups based on the video footage of the rallies. The expertise levels were determined using a typology based on a continuum of 5 conative stages: (1) structural, (2) functional, (3) technical, (4) contextual, and (5) expertise. The video allowed empirical measurement of the duration of the rallies, and tri-axial accelerometers measured the intensity of the player's involvement. A principal component analysis showed that two dimensions explained 54.9% of the total variance in the data and that conative stage and empirical parameters during rallies (duration, intensity of the game) were correlated with axis 1, whereas duration and acceleration data between rallies were correlated with axis 2. A random forest algorithm showed that among the parameters considered, acceleration, duration of the rallies, and time between rallies could predict conative stages with a prediction accuracy above possibility. This study suggests that performance analysis benefits from the confrontation of subjective and objective data in order to design training plans according to the expertise level of the participants.


Assuntos
Desempenho Atlético/fisiologia , Aprendizado de Máquina , Esportes com Raquete/fisiologia , Acelerometria , Adolescente , Adulto , Algoritmos , Feminino , Humanos , Masculino , Destreza Motora/fisiologia , Análise de Componente Principal , Esportes com Raquete/classificação , Estudos de Tempo e Movimento , Adulto Jovem
18.
Sensors (Basel) ; 20(6)2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32183426

RESUMO

Racquet sports can provide positive benefits for human healthcare. A reliable detection device that can effectively distinguish movement with similar sub-features is therefore needed. In this paper, a racquet sports recognition wristband system and a multilayer hybrid clustering model are proposed to achieve reliable activity recognition and perform number counting. Additionally, a Bluetooth mesh network enables communication between a phone and wristband, and sets-up the connection between multiple devices. This allows users to track their exercise through the phone and share information with other players and referees. Considering the complexity of the classification algorithm and the user-friendliness of the measurement system, the improved multi-layer hybrid clustering model applies three-level K-means clustering to optimize feature extraction and segmentation and then uses the density-based spatial clustering of applications with noise (DBSCAN) algorithm to determine the feature center of different movements. The model can identify unlabeled and noisy data without data calibration and is suitable for smartwatches to recognize multiple racquet sports. The proposed system shows better recognition results and is verified in practical experiments.


Assuntos
Exercício Físico/fisiologia , Esportes com Raquete/classificação , Esportes com Raquete/fisiologia , Dispositivos Eletrônicos Vestíveis , Acelerometria/instrumentação , Adulto , Algoritmos , Análise por Conglomerados , Desenho de Equipamento , Feminino , Humanos , Internet das Coisas , Aprendizado de Máquina , Masculino , Processamento de Sinais Assistido por Computador , Punho/fisiologia , Adulto Jovem
19.
J Strength Cond Res ; 34(6): 1547-1554, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31453933

RESUMO

Kumahara, H, Ohta, C, Nabeshima, E, Nakayama, A, Mine, S, and Yamato, T. Dietary intake and energy expenditure during two different phases of athletic training in female collegiate lacrosse players. J Strength Cond Res 34(6): 1547-1554, 2020-This study aims to investigate the state of nutrient intake and energy expenditure (EE) among various phases of periodization in female collegiate lacrosse players. A total of 17 Japanese female collegiate lacrosse players (age: 20.0 ± 0.9 years) were enrolled in this study. Physical activity (PA) and dietary intake were assessed over each 1-week period during the training preparatory phase (P-phase) and transition phase (T-phase). The exercise training-related EE (EEE) and EE associated with other daily living activities (i.e., nonexercise activity thermogenesis [NEAT]), were measured using accelerometers and heart rate (HR) monitoring using the flex-HR method. The total daily EE during the P-phase was significantly higher than that of the T-phase (2,168 ± 248 vs. 1744 ± 138 kcal·d; p < 0.01); however, no significant differences were observed in the total energy intake. Moreover, EEE during the P-phase was significantly higher than that of the T-phase, whereas no significant difference was found in NEAT. Furthermore, no significant differences were noted in any macronutrient intake variable observed between the 2 phases (protein:fat:carbohydrate ratio: 12.6 ± 1.5:32.9 ± 3.9:54.1 ± 5.1% in the P-phase vs. 12.1 ± 1.7:30.7 ± 3.9:55.7 ± 5.2% in the T-phase). The carbohydrate and protein intake were below recommended levels during the P-phase. Conversely, the saturated fatty acid ratio was higher than the dietary goals for disease prevention. Based on the changes in the PA volume observed during different training phases, female collegiate lacrosse players did not attain optimal nutrient intake required for optimal athletic performance and health.


Assuntos
Desempenho Atlético/fisiologia , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Esportes com Raquete/fisiologia , Acelerometria , Atletas , Dieta , Feminino , Humanos , Universidades , Adulto Jovem
20.
J Strength Cond Res ; 34(1): 203-211, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29239991

RESUMO

Phomsoupha, M and Laffaye, G. Multiple repeated-sprint ability test with four changes of direction for badminton players (part 2): predicting skill level with anthropometry, strength, shuttlecock, and displacement velocity. J Strength Cond Res 34(1): 203-211, 2020-The goal of this study was: (a) to assess general and specific lower and upper limb force, shuttlecock velocity, displacement ability, and the anthropometric characteristics of badminton players at 5 skill levels, and (b) to predict individual players' number of points. We divided 83 participants into groups of novice (n = 15), intermediate (n = 16), skilled (n = 23), highly skilled (n = 14), and elite (n = 15) players. The number of points scored for each player performing tournaments (excluding novices) during the entire season was used as a continuous and dependent variable after logarithmic transformation for correlational study. Anthropometric measurements of height, mass, percentage of fat, and muscle were recorded, along with shuttlecock maximal velocity during smashes. Upper limb power and lower limb force were recorded during jumps and handgrip strength. We also assessed players' ability to move quickly around the court through an on-court multiple repetition-sprint ability in badminton (MRSAB) test with 4 changes of direction. All variables were combined in a multiple regression model. The main findings were that the major contributor to skill level is shuttlecock velocity (r = 0.86), the time taken to move during the MRSAB test (r = 0.85) and the squat jump height (r = 0.53). Anthropometric factors contribute only a little to the individual score point (2%). Finally, the multiple regression model reveals that log(number of points) = 4.91 + 0.042 × shuttle velocity - 0.029 × MRSABTime - 0.001 × squat jump height, with r = 0.86 and a relative respective contribution of each variable of 86, 13, and 1%.


Assuntos
Desempenho Atlético/fisiologia , Esportes com Raquete/fisiologia , Adulto , Antropometria , Desempenho Atlético/estatística & dados numéricos , Estatura , Peso Corporal , Teste de Esforço , Força da Mão , Humanos , Extremidade Inferior/fisiologia , Corrida , Extremidade Superior/fisiologia , Adulto Jovem
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