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1.
J Sports Sci ; 42(2): 146-159, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38433654

RESUMO

Swing bowling can influence the outcome of cricket matches, but technique characteristics and coaching practices have not been investigated at an elite level. This study aimed to provide insight into the perceived technique parameters, coaching practices and variables contributing to conventional new ball swing bowling in elite cricket. Six Australian Test match fast bowlers and six Australian international and national-level coaches were interviewed. A reflexive thematic analysis of interview transcripts generated themes associated with swing bowling. Most bowlers reported their technique allows them to naturally create either inswing or outswing, with technique variations used to create swing in the opposite direction. To increase delivery effectiveness, bowlers and coaches recommended pitching the ball closer to the batter in length and varying release positions along the crease. Coaches recommended making individualised technique adjustments, but suggested all bowlers could benefit from maintaining balance and forward momentum to create a consistent release position in repeated deliveries. This study could inform training strategies to alter techniques and improve swing bowling performance. Future research should investigate the physical qualities of fast bowlers and use biomechanical analyses to provide a deeper understanding of swing bowling.


Assuntos
Críquete , Esportes , Humanos , Austrália , Movimento (Física) , Fenômenos Biomecânicos
2.
Eur J Appl Physiol ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418703

RESUMO

PURPOSE: Understanding the test-retest reliability of physiological responses to load carriage influences the interpretation of those results. The aim of this study was to determine the test-retest reliability of physiological measures during loaded treadmill walking at 5.5 km h-1 using the MetaMax 3B. METHODS: Fifteen Australian Army soldiers (9 male, 6 female) repeated two 12-min bouts of treadmill walking at 5.5 km h-1 in both a 7.2 kg Control condition (MetaMax 3B, replica rifle) and a 23.2 kg Patrol condition (Control condition plus vest) across three sessions, separated by one week. Expired respiratory gases and heart rate were continuously collected, with the final 3 min of data analysed. Ratings of Perceived Exertion and Omnibus-Resistance Exercise Scale were taken following each trial. Reliability was quantified by coefficient of variation (CV), intra-class correlation coefficients (ICC), smallest worthwhile change (SWC), and standard error of the measurement. RESULTS: Metabolic and cardiovascular variables were highly reliable (≤ 5% CV; excellent-moderate ICC), while the respiratory variables demonstrated moderate reliability (< 8% CV; good-moderate ICC) across both conditions. Perceptual ratings had poorer reliability during the Control condition (12-45% CV; poor ICC) than the Patrol condition (7-16% CV; good ICC). CONCLUSIONS: The test-retest reliability of metabolic and cardiovascular variables was high and relatively consistent during load carriage. Respiratory responses demonstrated moderate test-retest reliability; however, as the SWC differed with load carriage tasks, such data should be interpreted independently across loads. Perceptual measures demonstrated poor to moderate reliability during load carriage, and it is recommended that they only be employed as secondary measures.

3.
Sports Biomech ; : 1-17, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38190250

RESUMO

Compression garments are commonly used during athletic tasks. However, the effect of compression garments on balance, sprinting, jumping and change of direction performance requires further investigation. In the current study, 24 recreationally active participants (12 males, 12 females, age 27 ± 3 years) completed single-leg balance tasks, countermovement jumps, drop jumps, 10 m straight line sprints and change of direction tasks wearing either compression tights (COMP) or regular exercise tights (CON). There was a significant main effect of the condition for 10 m sprint time (p = 0.03, d = -0.18) and change of direction time (p = 0.03, d = -0.20) in favour of COMP. In addition, there was a significant, small difference (p = 0.05, d = -0.30) in ellipse area and a small (p = 0.16, d = 0.21) difference in balance time in favour of COMP during a single-leg balance task. There were no significant differences between trials for any of the other balance or jump tests (p > 0.05). The application of compression tights during exercise may offer small benefits to the performance of balance and change of direction tasks, though these benefits are likely within the typical error of measurement for the tests used.

4.
J Sports Sci ; 41(8): 788-795, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37537860

RESUMO

Coaches use physically constraining tools to supplement their coaching when developing sport-specific skills, however, their effectiveness is unknown. This scoping review aimed to understand the efficacy of physically constraining tools used in racket, stick, and club sports for grip-specific skill development. This scoping review followed the Joanna Briggs Institute methodology and PRISMA guidelines. Peer-reviewed research, including quasi-experimental, true-experimental, case studies, and grey literature were considered. Peer-reviewed sources were searched on Web of Science, Medline, and SPORTDiscus until October 6th, 2022. Exclusion criteria were (1) not original peer-reviewed research; (2) disabled participants or used for rehabilitation; or (3) not available in English. Data extracted were the type of tool, research foci, measures, and outcomes of the tool's efficacy. Zero peer-reviewed sources were identified on the efficacy of using physically constraining tools for grip-specific skill development. Common trends identified from the excluded sources were explored to provide a basis for the importance of using physically constraining tools for grip-specific skill development. Many tools are used in coaching despite their unclear efficacy, however, the current results can guide future work to assess the acute and longitudinal effects of using these tools, specifically within the development and performance of sport-specific skills.


Assuntos
Esportes , Humanos , Suplementos Nutricionais
5.
Scand J Med Sci Sports ; 33(10): 2039-2045, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37430459

RESUMO

Acquisition evaluations are expensive, have a high time liability, and tend to prioritize engineering requirements over human factors and good experimental design. Shooting serials usually consist of static prone shooting to minimize movement variability, increase reliability of accuracy and timing data or use a single data point to make acquisition decisions. To better understand the number of trials required to achieve representative performance of accuracy and timing, 60 shots from the standing unsupported position while cyclically moving the weapon from the low ready to shoot was utilized. Intra-class correlations, standard error of measurement, minimal detectable change, and sequential averaging analysis (SAA) were used to evaluate the variables of radial error, shot interval, x-bias and y-bias over the 60 shots. The number of trials required to achieve an intraclass correlation of greater than 0.8 ranged from 2 (shot interval) to 58 (y-bias), whereas SAA varied between 3 (x-bias) and 43 (shot interval) trials. When averaging 10 shots at a time, the moving intraclass correlation remained above 0.8 for radial error and y-bias between 7 and 15 shots, shot interval from the second shot, but x-bias never reached 0.8. The number of trials required to satisfy each reliability method was inconsistent, in line with previous literature. Given the limitations identified in the literature as well as practical considerations such as the preference for prioritizing radial error reasonable performance stability can be achieved after 15 shots, and using the moving intraclass correlation results it is recommended that the first six shots are discarded with the following nine shots used for analysis.


Assuntos
Armas de Fogo , Movimento , Humanos , Reprodutibilidade dos Testes , Posição Ortostática
6.
Sports Med Open ; 9(1): 38, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37256515

RESUMO

Representative learning design (RLD) in sport is a well-established concept in both theory and practice. The goal of RLD is to faithfully replicate competition environments in training settings to benefit improvement in athletic performance. There is currently little research that considers how representative an activity needs to be to facilitate learning transfer, and how that level of representativeness might fluctuate between activities or sessions, and across competitive cycles. Similarly, there is no existing research that specifically considers the elevated workload (in cognitive and physical load) of highly representative training, and the potential impacts of chronic overuse of these highly demanding activities. This paper addresses these limitations, making a case for the application of RLD that considers the level of representativeness (fidelity) and the demands placed on athletes (load) from both a cognitive and physical perspective. This paper also suggests several categorisations of training activities that are based on their relative representativeness, level of imposed demands, and the intended outcomes of the activity with reference to the perception-action cycle. The two core concepts of fidelity and load are combined for a new approach to representative training that allows practitioners to balance the benefits of representative training with the risks of imposing excessive load on athletes.

7.
PLoS One ; 18(3): e0277901, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36857370

RESUMO

Youth footballers need to be developed to meet the technical, tactical, and physical demands of professional level competition, ensuring that the transition between competition levels is successful. To quantify the physical demands, peak match intensities have been measured across football competition tiers, with team formations and tactical approaches shown to influence these physical demands. To date, no research has directly compared the physical demands of elite youth and professional footballers from a single club utilising common formations and tactical approaches. The current study quantified the total match and peak match running demands of youth and professional footballers from a single Australian A-League club. GPS data were collected across a single season from both a professional (n = 19; total observations = 199; mean ± SD; 26.7 ± 4.0 years) and elite youth (n = 21; total observations = 59; 17.9 ± 1.3 years) team. Total match demands and peak match running demands (1-10 min) were quantified for measures of total distance, high-speed distance [>19.8 km·h-1] and average acceleration. Linear mixed models and effect sizes identified differences between competition levels. No differences existed between competition levels for any total match physical performance metric. Peak total and high-speed distances demands were similar between competitions for all moving average durations. Interestingly, peak average acceleration demands were lower (SMD = 0.63-0.69) in the youth players across all moving average durations. The data suggest that the development of acceleration and repeat effort capacities is crucial in youth players for them to transition into professional competition.


Assuntos
Futebol Americano , Futebol , Humanos , Adolescente , Austrália , Aceleração , Modelos Lineares
8.
Biol Sport ; 40(1): 311-319, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36636178

RESUMO

Temporal changes in the total running demands of professional football competition have been well documented, with absolute running demands decreasing in the second half. However, it is unclear whether the peak match running demands demonstrate a similar decline. A total of 508 GPS files were collected from 44 players, across 68 matches of the Australian A-League. GPS files were split into the 1st and 2nd half, with the peak running demands of each half quantified across 10 moving average durations (1-10 min) for three measures of running performance (total distance, high-speed distance [> 19.8 km · h-1] and average acceleration). Players were categorised based on positional groups: attacking midfielder (AM), central defender (CD), defensive midfielder (DM), striker (STR), wide defender (WD) and winger (WNG). Linear mixed models and effect sizes were used to identify differences between positional groups and halves. Peak running demands were lower in the second half for STR across all three reported metrics (ES = 0.60-0.84), with peak average acceleration lower in the second half for DM, WD and WNG (ES = 0.60-0.70). Irrespective of match half, AM covered greater peak total distances than CD, STR, WD and WIN (ES = 0.60-2.08). Peak high-speed distances were greater across both halves for WIN than CD, DM and STR (ES = 0.78-1.61). Finally, STR had lower peak average acceleration than all positional groups across both halves (ES = 0.60-1.12). These results may help evaluate implemented strategies that attempt to mitigate reductions in second half running performance and inform position specific training practices.

9.
Gait Posture ; 100: 236-242, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36640597

RESUMO

BACKGROUND: Load carriage is a fundamental requirement for military personnel that commonly results in lower-limb injuries. Coupling variability represents a potential injury mechanism for such repetitive tasks and its unknown whether external loads and biological sex affect coupling variability during load carriage. RESEARCH QUESTION: Is there a sex-by-load interaction during load carriage at self-selected walking speeds? METHODS: Twenty-six participants (13 males, 13 females) completed three 10-minute treadmill-based trials wearing body-borne external load (0 %BM, 20 %BM, and 40 %BM) at load-specific self-selected walking speeds. A Vicon motion capture system tracked markers with a lower-body direct-kinematic model calculating sagittal-plane segment kinematics of the thigh, shank, and foot across 19 strides. Continuous relative phase standard deviation (CRPv) provided a measure of coupling variability for each coupling angle (Thigh-Shank and Shank-Foot). The CRPv for each load and sex was compared using statistical parametric mapping repeated measures ANOVA and paired t tests. RESULTS: Significant sex-by-load interactions were reported for the Thigh-Shank coupling. Males demonstrated no significant load differences in CRPv, however, females displayed significantly higher CRPv in the 40 %BM than the 0 %BM condition. A significant main effect of load was observed in the Shank-Foot coupling, with the 40 %BM having significantly greater CRPv than the other load conditions. SIGNIFICANCE: Both biological sex and external loads significantly affected CRPv during load carriage at self-selected walking speeds. Females demonstrated greater CRPv at the heavier loads, suggesting that the perturbation from the heavier mass increases coupling variability, which may also be amplified by a greater total passive load due to their relatively higher adipose tissue compared to males. The consistent CRPv in males suggests that higher relative loads may be required to change coupling variability. Collectively, these results suggest that external load affects the coupling variability of males and females differently, providing potential for injury screening and monitoring programs.


Assuntos
, Extremidade Inferior , Masculino , Feminino , Humanos , Coxa da Perna , Perna (Membro) , Fenômenos Biomecânicos , Suporte de Carga , Caminhada , Marcha
10.
J Strength Cond Res ; 37(1): 161-166, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36515601

RESUMO

ABSTRACT: Peek, RJ, Carey, DL, Middleton, KJ, Gastin, PB, and Clarke, AC. Association between position-specific impact and movement characteristics of professional rugby union players during game play. J Strength Cond Res 37(1): 161-166, 2023-The aim of this study was to understand the association between impact and movement characteristics during whole game and peak 1- to 10-minute rolling windows in professional rugby union. Maximal impact (impacts·min-1) and corresponding running (m·min-1) characteristics as well as maximal running (m·min-1) and corresponding impact (impacts·min-1) characteristics were obtained for 160 athletes from 4 teams across the 2018 and 2019 Super Rugby seasons. A linear mixed-effects model reported a positive association between whole-game running and impacts, where greater impact characteristics corresponded with greater running characteristics. The average 1-minute peak running characteristics (150-160 m·min-1) typically occurred when no impacts occurred. The average 1-minute peak impact characteristics (4-6 impacts·min-1) corresponded with an average relative distance of 90-100 m·min-1. Worst case scenario observed impact characteristics as large as 15 impacts·min-1 with a corresponding relative distance of 140 m·min-1. When training for peak period characteristics, running may be completed in isolation; however, peak impacts often occur in conjunction with moderate to high running movements. Given running and impact characteristics can appear concurrently within game play, this highlights the need to train them accordingly. As such, when prescribing training drills to replicate the peak characteristics in rugby union, consideration should be taken for both running and impact characteristics.


Assuntos
Desempenho Atlético , Futebol Americano , Corrida , Humanos , Rugby , Movimento , Sistemas de Informação Geográfica
11.
Sci Med Footb ; 7(3): 229-234, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35839520

RESUMO

INTRODUCTION: There is limited research on the on-field performance of previously concussed athletes. The aim of this exploratory study was to investigate athlete technical performance pre- and post-concussion in Australian Football. METHODS: Using publicly available data, male athletes who sustained a concussion during the 2016-19 professional Australian Football League seasons were analysed across five games pre- and post-concussion (concussion events n = 41, age 25.4 ± 3.5 years; control n = 39, age 25.2 ± 3.6 years). Mean technical performance metrics (goals, time-on-ground percentage, kicks, ground ball and disposal efficiency, contested marks) over the five games pre- and post-concussion, as well as within-athlete performance variability measures (standard deviation and coefficient of variation) were analysed. RESULTS: Results showed no significant group-by-time interactions, nor effect of time (pre-post) for any technical performance metric. Similarly, the within-athlete standard deviation and coefficient of variation of technical performance metrics showed no group-by-time interaction, nor effect for time. CONCLUSION: This retrospective study has shown that athlete performance averaged over five games is not affected post-concussion in elite men's Australian Football. Further prospective studies controlling for contextual match factors based on opposition and environmental conditions may be required to identify potential in-game technical performance changes following return-to-play from concussion.


Assuntos
Concussão Encefálica , Humanos , Masculino , Adulto Jovem , Adulto , Estudos Retrospectivos , Estudos Prospectivos , Austrália/epidemiologia , Concussão Encefálica/epidemiologia , Esportes de Equipe
12.
Ergonomics ; 66(9): 1246-1254, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36326486

RESUMO

Gait stability in soldiers can be affected by task constraints that may lead to injuries. This study determined the effects of weapon handling and speed on gait stability in seventeen soldiers walking on a treadmill with and without a replica weapon at self-selected (SS), 3.5 km·h-1, 5.5 km·h-1, and 6.5 km·h-1 while carrying a 23-kg load. Local dynamic stability was measured using accelerometry at the sacrum (LDESAC) and sternum (LDESTR). No significant weapon and speed interaction were found. A significant effect of speed for the LDESAC, and a significant effect of speed and weapon for the LDESTR were found. Per plane analyses showed that the weapon effect was consistent across all directions for the LDESTR but not for LDESAC. Weapon handling increased trunk but did not affect pelvis stability. Speed decreased stability when walking slower than SS and increased when faster. These findings can inform injury prevention strategies in the military. Practitioner summary: We determined the effects of two constraints in soldier's walking stability, weapon handling and speed, measured at the trunk and sacrum. No constraints interactions were found, however, lower stability when walking slow and greater stability with the weapon at the trunk can inform preventive strategies in military training.


Assuntos
Militares , Humanos , Marcha , Caminhada , Pelve , Fenômenos Biomecânicos
13.
Sports Biomech ; : 1-14, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266941

RESUMO

Foot strikes of the pace-bowling delivery stride produce large ground reaction forces, which may be linked to injury, yet the biomechanics of the follow-through are unknown. This study assessed tibial accelerations across the delivery and follow-through foot strikes in pace bowlers and evaluated relationships between these measures and five common pace-bowling intensity metrics. Fifteen sub-elite male pace bowlers performed deliveries at warm-up, match, and maximal intensities. Tibial accelerations were measured using tibial-mounted inertial measurement units and recorded at back- and front-foot initial and re-contacts. A trunk-worn global navigation satellite system unit measured PlayerLoad™, run-up speed, and distance. Ball speed and perceived exertion measures were also recorded. A linear mixed model showed statistical significance of prescribed intensities (p < .001) and foot strike for tibial acceleration (p < .001). Tibial accelerations showed positive increases with changes in prescribed intensity (p < .05). The greatest magnitude of tibial acceleration was found at back foot re-contact (mean ± SD; 1139 ± 319 m/s2). Repeated-measures correlations of tibial acceleration between foot contacts were weak (r = 0.2-0.4). The greatest magnitude of tibial acceleration reported at back foot re-contact may have implications for injury incidence, representing an important avenue for future pace bowling research.

14.
Biol Sport ; 39(4): 985-994, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36247961

RESUMO

The peak match running demands of football (soccer) have been quantified across time durations of 1-10 min, however, little is known as to when the peak match running demands occur within match play. Data were collected from 44 elite footballers, across 68 fixtures (Files = 413, mean ± SD; 11 ± 8 observations per player, range; 1-33), with peak match running demands quantified for each playing half at ten incremental rolling average durations (1 min rolling averages, 2 min rolling averages, etc.). Data were assessed if players completed the full match. Three measures of running performance were assessed total distance (TD), high-speed distance (> 19.8 km · h-1) (HSD) and average acceleration (AveAcc)], with the in-game commencement time of the peak running demands recorded. Descriptive statistics and normality were calculated for each rolling average duration, with the self-containment of shorter rolling average epochs within longer epochs also assessed (e.g. Do the 1 min peak running demands occur within the 10 min peak running demands). Peak TD and AveAcc demands occurred early in each half (median time = 7-17 min and 6-16 min, respectively). Conversely, peak HSD covered was uniformly distributed (Skewness = 0-0.5, Kurtosis = 1.7-2.0). There were low-moderate levels of self-containment for each peak match running period (10-51%), dependent upon metric. Peak match running demands for TD and AveAcc occurred at similar stages of a match where TD and acceleration volumes are typically greatest, whereas peak HSD demands appeared more unpredictable. These timings may help inform training prescriptions in preparation of athletes for competition.

15.
Biol Sport ; 39(4): 833-838, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36247963

RESUMO

Peak match running intensities have recently been introduced to quantify the peak running demands of football competition, across incremental time intervals, to inform training practices. However, their between-match variation is yet to be comprehensively reported, limiting the ability to determine meaningful changes in peak match running intensities. The current study aimed to quantify the between-match variability in peak match running intensities across discrete moving average durations (1-10 min). GPS data were collected from 44 elite football players across 68 matches (mean ± SD; 13 ± 10 observations per player). For inclusion players must have completed 70mins of a match across a minimum of two matches. Performance metrics included total and high-speed (> 19.8 km · h-1) running distances and average acceleration (m · s-2), expressed relative to time. For each metric, the coefficient of variation and smallest worthwhile difference were calculated. The peak match running intensity data was similar to previously reported data from various football competitions. The between-match CV of relative total distance ranged between 6.8-7.3%, with the CV for average acceleration and relative high-speed running being 5.4-5.8% and 20.6-29.8%, respectively. The greater variability observed for relative high-speed running is likely reflective of the varying constraints and contextual factors that differ between matches. The reported between-match variability helps to provide context when interpreting match performance and prescribing training drills using peak match running intensity data.

16.
Sports Biomech ; : 1-16, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35968770

RESUMO

To assess the validity and between-unit agreement of velocity monitoring devices during incrementally-loaded countermovement jumps (CMJ), 16 males (24.0 ± 3.5 yr) completed 12 CMJs on a force plate (FP). Performance variables were collected through two linear position transducers (GymAware [GA]) and four accelerometer-based devices (two PUSH units, two Bar Sensei units). Pearson correlations (r) and coefficients of variation (CV) demonstrated strong to very-strong relationships (r = 0.60-0.88) and poor agreement (CV = 11.7-25.3%) between FP and GA, and moderate to very-strong relationships (r = 0.31-0.81) and poor agreement (CV = 10.1-24.2%) between FP and PUSH. Between-unit comparisons demonstrated moderate to very-strong relationships (r = 0.50-0.88) with poor agreement (CV = 10.8-26.6%) for GA, and very weak to very-strong relationships (r = 0.01-0.87) with moderate to poor agreement (CV = 9.1-24.1%) for PUSH. Bar Sensei units were excluded from analyses. Loaded CMJ data collected with either device displayed poor agreement with a FP. Velocity monitoring devices demonstrate poor validity across all loads; however, GA demonstrated strong between-unit agreement. A FP should be utilised to accurately assess CMJ performance at all times.

17.
J Sci Med Sport ; 25(9): 776-782, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35662534

RESUMO

OBJECTIVES: This study identifies the distribution (as a percentage of the positional peak) and occurrence (within a half) of 1-min movement characteristics (m·min-1) and contact-based events (impact·min-1) during professional rugby union game play. DESIGN: Within 95 rugby union games, players wore global positioning system (GPS) devices (n = 1422 player-game files, 160 athletes). One-minute rolling-window averages were calculated with the maximum and mean value being recorded for each dependent variable; relative distance (m·min-1) and impacts (impact·min-1), then standardised by the positional peak mean. METHODS: The distribution of these variables accumulated in 10% increments of the peak were determined as was their occurrence throughout a playing half for each positional group. RESULTS: The greatest distribution of game play (%) was observed at ~30-39% of the positional peak for movement and with no impacts. The greatest occurrence of maximum positional peak 1-min movement periods occurred at the beginning of each half and declined as the half went on. Peak impact characteristics, however, were found to be more sporadic across a half. CONCLUSIONS: These findings suggest that the distribution of positional peak 1-min movement (80-100%+) and peak impacts (4+) were <5% of overall game play, and observed <2% of total occurrences. This highlights that practitioners should alter training drills by time, volume, and intensity in order to replicate the peak intensities of game play.


Assuntos
Desempenho Atlético , Futebol Americano , Corrida , Sistemas de Informação Geográfica , Humanos , Masculino , Movimento , Rugby
18.
Sports Biomech ; : 1-20, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35730365

RESUMO

The purpose of this study was to compare the upper limb kinematic chain of tennis players using either an eastern or continental non-dominant grip position during the forward swing of the double-handed backhand stroke. Sixteen right-handed tennis players performed backhands using two non-dominant grip positions (eastern and continental), aiming for two cross-court zones (deep and short). Trajectory data were captured using sixty reflective markers attached to the upper limb and racket using a 12-camera Vicon motion capture system (250 Hz). Peak angular velocity was significantly greater for multiple joint rotations at the dominant shoulder and entire non-dominant limb in the eastern grip. Subsequently, greater peak racket head angular velocity and post-impact ball speed were generated by the eastern grip, while shot accuracy was similar between grip types. There was delayed dominant shoulder peak adduction angular velocity for the continental grip, possibly due to a lack of skill familiarity causing changes in coordinative patterns. Collectively, the non-dominant grip position appears to influence proximal and distal upper limb movement. Future research should explore upper limb segment coordination comparing preferred and non-preferred double-handed backhand techniques and complete inter-disciplinary investigations to understand what grip positions are most effective for individuals to learn double-handed backhands.

19.
J Sports Sci ; 40(11): 1214-1219, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35501668

RESUMO

The aim of this study was to determine whether there are differences in the accuracy and consistency of repeated lawn bowl deliveries between different bowling conditions and to describe the bias of bowls that missed the target (jack). Twenty-seven elite lawn bowl athletes were recruited to partake in the study. Participants delivered 16 bowls in four conditions: (i) forehand and (ii) backhand towards a target 23 metres away and (iii) forehand and (iv) backhand towards a target 27 metres away. The resting position of each bowl relative to the jack was described in terms of absolute displacement, width displacement and length displacement. For each participant and each condition, the average absolute displacement of deliveries was calculated as a measure of accuracy; the average width and length displacement was used to describe the bias of deliveries; and the bivariate variable error of absolute displacement was calculated as a measure of consistency. The forehand towards a target 23 metres away was significantly less accurate and consistent when compared with other conditions. There was a bias for greater width displacement of both forehand deliveries (p < 0.001). Analysing lawn bowls in this detail provides specific areas for coaching to improve lawn bowling performance.


Assuntos
Esportes , Atletas , Fenômenos Biomecânicos , Humanos
20.
J Sports Sci ; 40(16): 1772-1800, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35446231

RESUMO

The application of acceleration and deceleration data as a measure of an athlete's physical performance is common practice in team sports. Acceleration and deceleration are monitored with athlete tracking technologies during training and games to quantify training load, prevent injury and enhance performance. However, inconsistencies exist throughout the literature in the reported methodological procedures used to quantify acceleration and deceleration. The object of this review was to systematically map and provide a summary of the methodological procedures being used on acceleration and deceleration data obtained from athlete tracking technologies in team sports and describe the applications of the data. Systematic searches of multiple databases were undertaken. To be included, studies must have investigated full body acceleration and/or deceleration data of athlete tracking technologies. The search identified 276 eligible studies. Most studies (60%) did not provide information on how the data was derived and what sequence of steps were taken to clean the data. Acceleration and deceleration data were commonly applied to quantify and describe movement demands using effort metrics. This scoping review identified research gaps in the methodological procedures and deriving and cleaning techniques that warrant future research focussing on their effect on acceleration and deceleration data.


Assuntos
Corrida , Esportes de Equipe , Humanos , Desaceleração , Sistemas de Informação Geográfica , Aceleração , Atletas
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