Pub Date : 2024-02-01DOI: 10.1177/17479541231219969
Niklas Karlsson, Anders Lunander
The baton exchanges are undoubtedly the most critical parts of the 4 × 100 m relay race. Timing of the outgoing runner is critical. In this paper we analyze the race as a minimization problem under uncertainty. We formulate a stochastic model in which the outgoing runner at the baton exchange cannot perfectly assess the incoming runner's exact location relatively a checkmark position, and therefore potentially misjudges the right moment to start running. Also, the team members’ daily shape is subject to uncertainty. To understand the effect of these two random variables—incoming runners’ distance to checkmark and the daily shape of the running team—we conduct a simulation study to investigate the trade-off between the team's expected race time and their probability of being disqualified due to overrunning the takeover zone. Conditioning on a low disqualification probability, the difference in expected race time is shown to be substantial between teams with different variation in distance assessment and forecasting running performance, respectively.
{"title":"A stochastic analysis of the 4 × 100 m relay","authors":"Niklas Karlsson, Anders Lunander","doi":"10.1177/17479541231219969","DOIUrl":"https://doi.org/10.1177/17479541231219969","url":null,"abstract":"The baton exchanges are undoubtedly the most critical parts of the 4 × 100 m relay race. Timing of the outgoing runner is critical. In this paper we analyze the race as a minimization problem under uncertainty. We formulate a stochastic model in which the outgoing runner at the baton exchange cannot perfectly assess the incoming runner's exact location relatively a checkmark position, and therefore potentially misjudges the right moment to start running. Also, the team members’ daily shape is subject to uncertainty. To understand the effect of these two random variables—incoming runners’ distance to checkmark and the daily shape of the running team—we conduct a simulation study to investigate the trade-off between the team's expected race time and their probability of being disqualified due to overrunning the takeover zone. Conditioning on a low disqualification probability, the difference in expected race time is shown to be substantial between teams with different variation in distance assessment and forecasting running performance, respectively.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"213 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139956147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-01DOI: 10.1177/17479541241228059
Alexandru Nicolae Ungureanu, Corrado Lupo, Matteo Contardo, Paolo Riccardo Brustio
Despite the recent popularity of padel tennis and extensive scientific research on technical and tactical performance, anthropometric, biomechanical, and physiological characteristics, there is still a lack of long-term retrospective investigation. Therefore, this study aimed to analyze key performance indicators (KPIs) to provide the changes in these indicators over a decade spanning from 2011 to 2021. The sample included 45 (i.e. 100 sets; 957 games; 5743 points; and 54,918 shots) professional men's matches (Padel Pro Tour and World Padel Tour finals and semifinals) from three different sports seasons (2011, 2016, and 2021). KPIs related to time motion and technical and tactical analysis (i.e. unforced errors and winner shots) were examined. A series of linear mixed models was performed to investigate difference among competition years (2011, 2016, and 2021). Comparing the evolution of the game across the observed decade, it emerged a more progressive intense game (more explosive and rapid playing actions), decreasing number of shots per point (8.8 vs 9.5), and an increasing number of shots per minute (44.2 vs 40.0). Further, an increase in the importance of efficiency in overhead shots (unforced errors from bandeja/vibora +116% from 2011 to 2016) and responding to serve shots (unforced errors from serve return +17% from 2011 to 2021) emerged. Therefore, the present findings are able to highlight the evolution playing of professional padel (i.e. fewer shots per point, shorter effective playing time, decreased average point durations, higher number of shots per minute), thus providing references to potential valuable training plans.
{"title":"Decoding the decade: Analyzing the evolution of technical and tactical performance in elite padel tennis (2011–2021)","authors":"Alexandru Nicolae Ungureanu, Corrado Lupo, Matteo Contardo, Paolo Riccardo Brustio","doi":"10.1177/17479541241228059","DOIUrl":"https://doi.org/10.1177/17479541241228059","url":null,"abstract":"Despite the recent popularity of padel tennis and extensive scientific research on technical and tactical performance, anthropometric, biomechanical, and physiological characteristics, there is still a lack of long-term retrospective investigation. Therefore, this study aimed to analyze key performance indicators (KPIs) to provide the changes in these indicators over a decade spanning from 2011 to 2021. The sample included 45 (i.e. 100 sets; 957 games; 5743 points; and 54,918 shots) professional men's matches (Padel Pro Tour and World Padel Tour finals and semifinals) from three different sports seasons (2011, 2016, and 2021). KPIs related to time motion and technical and tactical analysis (i.e. unforced errors and winner shots) were examined. A series of linear mixed models was performed to investigate difference among competition years (2011, 2016, and 2021). Comparing the evolution of the game across the observed decade, it emerged a more progressive intense game (more explosive and rapid playing actions), decreasing number of shots per point (8.8 vs 9.5), and an increasing number of shots per minute (44.2 vs 40.0). Further, an increase in the importance of efficiency in overhead shots (unforced errors from bandeja/vibora +116% from 2011 to 2016) and responding to serve shots (unforced errors from serve return +17% from 2011 to 2021) emerged. Therefore, the present findings are able to highlight the evolution playing of professional padel (i.e. fewer shots per point, shorter effective playing time, decreased average point durations, higher number of shots per minute), thus providing references to potential valuable training plans.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"55 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139956269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-31DOI: 10.1177/17479541241227329
Riaan van Tonder, James Craig Brown, Sean Surmon, Pierre Viviers, Wilbur Kraak, Keith A Stokes, Sharief Hendricks, Wayne Derman, Marelise Badenhorst
This study aimed to investigate the perceptions of key stakeholder groups, i.e. coaches, players, and referees, of a reduced maximum legal tackle height law variation trial in a collegiate amateur rugby competition. A pragmatic qualitative approach was used. Eighteen semi-structured interviews were performed. Thematic analysis was used to analyse the data. Three main law trial-related themes and four additional contextual themes were identified. The most important contextual factors include perceptions of resource scarcity of the implementation context, deficient concussion knowledge and lack of education among all stakeholder groups, tackle technique deficiencies, and an entrenched culture of a dismissive attitude towards serious injuries and non-disclosure of concussion by players. Real-world challenges such as inconsistent sanctioning during gameplay, multi-tackler tackles, and player fatigue underscore the gap between the theoretical knowledge of the law and the complex, dynamic nature of its execution. Furthermore, deeply ingrained issues like entrenched tackle techniques, the quality of coaching, and prevailing attitudes towards concussion compounded these challenges, indicating a need for a more comprehensive approach to bridge the divide between understanding and implementation. Despite these challenges, several participants felt the law variation was still more effective than the existing law; and that it created more awareness around concussion, while sending a clear message that player welfare is being taken seriously. Collectively these factors indicate the difficulty of addressing a complex problem such as concussion, with a law variation intervention in a challenging (resource-constrained) setting.
{"title":"Stakeholder perceptions of a tackle law variation to reduce concussion incidence in community rugby union: A qualitative study","authors":"Riaan van Tonder, James Craig Brown, Sean Surmon, Pierre Viviers, Wilbur Kraak, Keith A Stokes, Sharief Hendricks, Wayne Derman, Marelise Badenhorst","doi":"10.1177/17479541241227329","DOIUrl":"https://doi.org/10.1177/17479541241227329","url":null,"abstract":"This study aimed to investigate the perceptions of key stakeholder groups, i.e. coaches, players, and referees, of a reduced maximum legal tackle height law variation trial in a collegiate amateur rugby competition. A pragmatic qualitative approach was used. Eighteen semi-structured interviews were performed. Thematic analysis was used to analyse the data. Three main law trial-related themes and four additional contextual themes were identified. The most important contextual factors include perceptions of resource scarcity of the implementation context, deficient concussion knowledge and lack of education among all stakeholder groups, tackle technique deficiencies, and an entrenched culture of a dismissive attitude towards serious injuries and non-disclosure of concussion by players. Real-world challenges such as inconsistent sanctioning during gameplay, multi-tackler tackles, and player fatigue underscore the gap between the theoretical knowledge of the law and the complex, dynamic nature of its execution. Furthermore, deeply ingrained issues like entrenched tackle techniques, the quality of coaching, and prevailing attitudes towards concussion compounded these challenges, indicating a need for a more comprehensive approach to bridge the divide between understanding and implementation. Despite these challenges, several participants felt the law variation was still more effective than the existing law; and that it created more awareness around concussion, while sending a clear message that player welfare is being taken seriously. Collectively these factors indicate the difficulty of addressing a complex problem such as concussion, with a law variation intervention in a challenging (resource-constrained) setting.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"2014 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139956165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-31DOI: 10.1177/17479541231226413
Drumond Gilo da Silva, Rodrigo Fabio Bezerra da Silva, Petrus Gantois, Vitor Bertoli Nascimento, Fábio Yuzo Nakamura, Fabiano de Souza Fonseca
BackgroundThe perception of bar velocity loss (PVL) can be used as an alternative method for autoregulating intraset repetitions during velocity-based training. This study analyzed the accuracy and reliability of the PVL as a method to autoregulate the intraset repetitions using a moderate velocity loss (VL) threshold (15–30%).MethodsA total of 22 resistance-trained men were familiarized with the PVL in a single session. Test–retest was performed in two sessions 1 week apart, in which participants completed three sets of bench press and back squat at 40, 60, and 80% 1 repetition maximum (1RM). Participants stopped the sets when they reached a moderate VL zone using their PVL. Accuracy was assessed by analyzing whether the mean VL (actual) and the lower and upper limits of the confidence interval (CI) (95%) of each set were within the established VL range and quantifying the relative frequency of correctly interrupted sets. Test–retest reliability was examined by the intraclass correlation coefficient and coefficient of variation.ResultsPVL showed acceptable accuracy in both exercises at 60 and 80% 1RM (50–65% success rate) and retest for all loads (53–76% success rate). Similar PVL percentages were observed between most of the sets for the test and retest ( p > 0.05). Accuracy improved during the retest, especially for bench press (40% 1RM) and back squat (40 and 80% 1RM). PVL was not reliable in the test–retest comparison.ConclusionPVL can be a strategy with acceptable accuracy to autoregulate the intraset repetitions in a moderate zone (VL15–30%), but its reliability does not appear satisfactory after one familiarization session.
{"title":"Accuracy and reliability of perception of bar velocity loss for autoregulation in resistance exercise","authors":"Drumond Gilo da Silva, Rodrigo Fabio Bezerra da Silva, Petrus Gantois, Vitor Bertoli Nascimento, Fábio Yuzo Nakamura, Fabiano de Souza Fonseca","doi":"10.1177/17479541231226413","DOIUrl":"https://doi.org/10.1177/17479541231226413","url":null,"abstract":"BackgroundThe perception of bar velocity loss (PVL) can be used as an alternative method for autoregulating intraset repetitions during velocity-based training. This study analyzed the accuracy and reliability of the PVL as a method to autoregulate the intraset repetitions using a moderate velocity loss (VL) threshold (15–30%).MethodsA total of 22 resistance-trained men were familiarized with the PVL in a single session. Test–retest was performed in two sessions 1 week apart, in which participants completed three sets of bench press and back squat at 40, 60, and 80% 1 repetition maximum (1RM). Participants stopped the sets when they reached a moderate VL zone using their PVL. Accuracy was assessed by analyzing whether the mean VL (actual) and the lower and upper limits of the confidence interval (CI) (95%) of each set were within the established VL range and quantifying the relative frequency of correctly interrupted sets. Test–retest reliability was examined by the intraclass correlation coefficient and coefficient of variation.ResultsPVL showed acceptable accuracy in both exercises at 60 and 80% 1RM (50–65% success rate) and retest for all loads (53–76% success rate). Similar PVL percentages were observed between most of the sets for the test and retest ( p > 0.05). Accuracy improved during the retest, especially for bench press (40% 1RM) and back squat (40 and 80% 1RM). PVL was not reliable in the test–retest comparison.ConclusionPVL can be a strategy with acceptable accuracy to autoregulate the intraset repetitions in a moderate zone (VL15–30%), but its reliability does not appear satisfactory after one familiarization session.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"242 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139956148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-10DOI: 10.1177/17479541231210979
Leonardo Lamas, Matthew Heiner, Mario Ferreira, Arthur Moura, Wellington Rangel, Gilbert Fellingham, Victor Lage
No-gi Brazilian jiu-jitsu is a grappling-based combat sport performed without the jiu-jitsu uniform. It’s fast-growing popularity has been influenced by the contributions to competitors’ performance in mixed martial arts tournaments. This study aimed to analyze the frequency of actions, the transitions between them, and their reward–risk balance—the probability of submitting minus the probability of being submitted—among top-level competitors. Data encompassed all 93 matches (90 competitors) of the World Submission Fighting Championship-2019. Reliability was assessed by two experts (sports scientists, more than 10 years as no-gi Brazilian jiu-jitsu competitors). Data analyses used Bayesian methods for inference. Posterior distributions of the mean frequencies of actions indicate that the main actions (e.g. takedown, sweep, and back-take) tended to occur less than once per competitor in each match, except by the submission attempt (point estimate of 1.03 per match). The highest estimates for the transition probabilities between match actions were within-competitor—a guard pass action to another guard pass action (0.30); between-competitors—a takedown attempt to a submission attempt (0.15). Most of the actions presented positive reward-risk balance, particularly for the back-take, which showed the highest probability of direct transition to submission (0.45). The dynamic analysis of no-gi Brazilian jiu-jitsu matches evidenced some preferential actions’ transitions associated with winning. Findings should enhance the accuracy of performance prediction and provide evidence-based recommendations for coaches.
{"title":"No-gi Brazilian jiu-jitsu: A Markovian analysis of elite-level combat dynamics","authors":"Leonardo Lamas, Matthew Heiner, Mario Ferreira, Arthur Moura, Wellington Rangel, Gilbert Fellingham, Victor Lage","doi":"10.1177/17479541231210979","DOIUrl":"https://doi.org/10.1177/17479541231210979","url":null,"abstract":"No-gi Brazilian jiu-jitsu is a grappling-based combat sport performed without the jiu-jitsu uniform. It’s fast-growing popularity has been influenced by the contributions to competitors’ performance in mixed martial arts tournaments. This study aimed to analyze the frequency of actions, the transitions between them, and their reward–risk balance—the probability of submitting minus the probability of being submitted—among top-level competitors. Data encompassed all 93 matches (90 competitors) of the World Submission Fighting Championship-2019. Reliability was assessed by two experts (sports scientists, more than 10 years as no-gi Brazilian jiu-jitsu competitors). Data analyses used Bayesian methods for inference. Posterior distributions of the mean frequencies of actions indicate that the main actions (e.g. takedown, sweep, and back-take) tended to occur less than once per competitor in each match, except by the submission attempt (point estimate of 1.03 per match). The highest estimates for the transition probabilities between match actions were within-competitor—a guard pass action to another guard pass action (0.30); between-competitors—a takedown attempt to a submission attempt (0.15). Most of the actions presented positive reward-risk balance, particularly for the back-take, which showed the highest probability of direct transition to submission (0.45). The dynamic analysis of no-gi Brazilian jiu-jitsu matches evidenced some preferential actions’ transitions associated with winning. Findings should enhance the accuracy of performance prediction and provide evidence-based recommendations for coaches.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"116 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135137788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-07DOI: 10.1177/17479541231200526
Túlio Bernardo Macedo Alfano Moura, Juliane Cristine Leme, Fábio Yuzo Nakamura, Jefferson Rosa Cardoso, Felipe Arruda Moura
Sprint studies present several variables and methodologies for biomechanical analysis in different phases of running. The variability in the analysis of the sample and distance covered may impede the application of the results in track and field athletes. The objective of this systematic review was to characterize the determinant biomechanical variables analyzed in the literature in each sprint phase. Four electronic databases were used (MEDLINE, Web of Science, SportDiscus, and Scopus). Only biomechanical studies with track and field athletes were selected. After the identification, screening, and eligibility process, 109 studies were included for qualitative synthesis and analyzed by the risk of bias assessment. The studies were classified in different sprint phases, according to the sprint task described by the authors (sprint start = 27, acceleration = 32, constant speed = 8, deceleration = 4, and not specified = 38). Factors such as the center of mass position, contact time, force applied on the rear block, and athletes’ ability to generate high amounts of force in the shortest possible time influence the sprint start performance. The acceleration phase is characterized by step frequency and step length transition, propulsive force, and minimization of braking force. Consequently, directing the resulting force as vertically as possible in the braking phase and as horizontally as possible in the anterior direction during the propulsive phase is important during the constant speed phase. In the deceleration phase, the decrease in step frequency and the increase in contact time may influence speed maintenance and, consequently, the result.
短跑研究为跑步不同阶段的生物力学分析提供了几个变量和方法。样本分析和覆盖距离的可变性可能会阻碍结果在田径运动员中的应用。本系统综述的目的是表征每个冲刺阶段文献中分析的决定性生物力学变量。使用了四个电子数据库(MEDLINE, Web of Science, SportDiscus和Scopus)。只选择了田径运动员的生物力学研究。经过鉴定、筛选和入选过程，纳入109项研究进行定性综合，并进行偏倚风险评估分析。根据作者描述的冲刺任务(冲刺开始= 27，加速= 32，匀速= 8，减速= 4，未指定= 38)，将研究分为不同的冲刺阶段。诸如重心位置、接触时间、施加在后块上的力以及运动员在尽可能短的时间内产生大量力的能力等因素都会影响短跑起跑的表现。加速阶段的特点是步进频率和步长过渡、推进力和制动力的最小化。因此，在恒速阶段，在制动阶段尽可能垂直地引导所产生的力，在推进阶段尽可能在前方向水平地引导所产生的力是很重要的。在减速阶段，步进频率的降低和接触时间的增加可能会影响速度保持，从而影响结果。
{"title":"Determinant biomechanical variables for each sprint phase performance in track and field: A systematic review","authors":"Túlio Bernardo Macedo Alfano Moura, Juliane Cristine Leme, Fábio Yuzo Nakamura, Jefferson Rosa Cardoso, Felipe Arruda Moura","doi":"10.1177/17479541231200526","DOIUrl":"https://doi.org/10.1177/17479541231200526","url":null,"abstract":"Sprint studies present several variables and methodologies for biomechanical analysis in different phases of running. The variability in the analysis of the sample and distance covered may impede the application of the results in track and field athletes. The objective of this systematic review was to characterize the determinant biomechanical variables analyzed in the literature in each sprint phase. Four electronic databases were used (MEDLINE, Web of Science, SportDiscus, and Scopus). Only biomechanical studies with track and field athletes were selected. After the identification, screening, and eligibility process, 109 studies were included for qualitative synthesis and analyzed by the risk of bias assessment. The studies were classified in different sprint phases, according to the sprint task described by the authors (sprint start = 27, acceleration = 32, constant speed = 8, deceleration = 4, and not specified = 38). Factors such as the center of mass position, contact time, force applied on the rear block, and athletes’ ability to generate high amounts of force in the shortest possible time influence the sprint start performance. The acceleration phase is characterized by step frequency and step length transition, propulsive force, and minimization of braking force. Consequently, directing the resulting force as vertically as possible in the braking phase and as horizontally as possible in the anterior direction during the propulsive phase is important during the constant speed phase. In the deceleration phase, the decrease in step frequency and the increase in contact time may influence speed maintenance and, consequently, the result.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"6 22","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135540479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-07DOI: 10.1177/17479541231211679
Lukáš Slovák, Javad Sarvestan, Fatemeh Alaei, Takehiro Iwatsuki, David Zahradník
The performance assessment of relevant biomechanical factors is essential for appropriate age-related training progression in volleyball spike (VS). This study aimed to investigate the differences in upper limbs’ (a) range of motion (ROM), (b) angular velocities, and (c) muscular activity during VS among under 16- (U-16), under 18- (U-18), and under 20- (U-20) year-old female volleyball players. The kinematic variables of the spike performances were recorded using six optoelectronic cameras (Vicon Motion system, UK). Additionally, the wireless Trigno system (Delsys, USA) was used to record the electromyographic signals. The one-way ANOVA (1d SPM analysis) exhibited a significantly greater wrist internal rotation ( p < .001), wrist adduction velocity (p < .001), and palmaris longus activity ( p < .001) in the acceleration phase in U-20, compared to the U-16 group. Additionally, the U-20 and the U-18 players portrayed a significantly greater shoulder external rotation ( p < .001) and internal angular velocity ( p = .035) relative to the U-16 group. A significantly greater pectoralis major (p < .001), biceps brachii ( p < .001), and anterior deltoid ( p < .001) activity was observed in the U-20 group, compared to younger groups. This study suggests that older players employ more upper limb muscular activities during spike with the presence of blocks, which enables them to hit the ball with greater velocities and direct the ball in their desired direction through increased wrist ROMs.
{"title":"Upper limb biomechanical differences in volleyball spikes among young female players","authors":"Lukáš Slovák, Javad Sarvestan, Fatemeh Alaei, Takehiro Iwatsuki, David Zahradník","doi":"10.1177/17479541231211679","DOIUrl":"https://doi.org/10.1177/17479541231211679","url":null,"abstract":"The performance assessment of relevant biomechanical factors is essential for appropriate age-related training progression in volleyball spike (VS). This study aimed to investigate the differences in upper limbs’ (a) range of motion (ROM), (b) angular velocities, and (c) muscular activity during VS among under 16- (U-16), under 18- (U-18), and under 20- (U-20) year-old female volleyball players. The kinematic variables of the spike performances were recorded using six optoelectronic cameras (Vicon Motion system, UK). Additionally, the wireless Trigno system (Delsys, USA) was used to record the electromyographic signals. The one-way ANOVA (1d SPM analysis) exhibited a significantly greater wrist internal rotation ( p < .001), wrist adduction velocity (p < .001), and palmaris longus activity ( p < .001) in the acceleration phase in U-20, compared to the U-16 group. Additionally, the U-20 and the U-18 players portrayed a significantly greater shoulder external rotation ( p < .001) and internal angular velocity ( p = .035) relative to the U-16 group. A significantly greater pectoralis major (p < .001), biceps brachii ( p < .001), and anterior deltoid ( p < .001) activity was observed in the U-20 group, compared to younger groups. This study suggests that older players employ more upper limb muscular activities during spike with the presence of blocks, which enables them to hit the ball with greater velocities and direct the ball in their desired direction through increased wrist ROMs.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"73 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135539543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-07DOI: 10.1177/17479541231211667
Ana Fernández de Ossó, Javier Pecci, Horacio Sánchez-Trigo, Diego Muñoz, Adrián Escudero-Tena, Juan León
Padel is a complex racket sport with a wide variety of technical actions and tactical possibilities. The aim was to compare the duration of the rallies, the number of shots, the shot frequency and the shot frequency between elite and amateur padel players of different genders, which is necessary to guide the training process. The results show that the duration of the rally is longer in elite padel than in amateur padel, both in men ( p < 0.001) and in women ( p < 0.001). In addition, according to gender, greater in women's padel than in men's padel, both in elite ( p < 0.001) and amateur ( p < 0.001). The number of shots per point is greater in elite padel than in amateur padel, both in men ( p < 0.001) and in women ( p < 0.001). Furthermore, according to gender, greater in women’s padel than in men’s padel in elite padel ( p < 0.001) and no significant differences were found in amateur padel ( p = 0.800). The shot frequency is longer in elite padel ( X̅: 0.87) than amateur padel ( X̅: 0.82) and in men padel ( X̅: 0.86) than women padel ( X̅: 0.82), although no significant differences were found. Finally, the player on the right tends to hits the ball less than the player on the left (except women elite players). These results are highly relevant for coaches, as they allow them to guide training processes and quantify the specific workloads of the match based on the gender and level of the players.
{"title":"Differences between genders and competitive levels on technical-tactical parameters in padel: Implications for training","authors":"Ana Fernández de Ossó, Javier Pecci, Horacio Sánchez-Trigo, Diego Muñoz, Adrián Escudero-Tena, Juan León","doi":"10.1177/17479541231211667","DOIUrl":"https://doi.org/10.1177/17479541231211667","url":null,"abstract":"Padel is a complex racket sport with a wide variety of technical actions and tactical possibilities. The aim was to compare the duration of the rallies, the number of shots, the shot frequency and the shot frequency between elite and amateur padel players of different genders, which is necessary to guide the training process. The results show that the duration of the rally is longer in elite padel than in amateur padel, both in men ( p < 0.001) and in women ( p < 0.001). In addition, according to gender, greater in women's padel than in men's padel, both in elite ( p < 0.001) and amateur ( p < 0.001). The number of shots per point is greater in elite padel than in amateur padel, both in men ( p < 0.001) and in women ( p < 0.001). Furthermore, according to gender, greater in women’s padel than in men’s padel in elite padel ( p < 0.001) and no significant differences were found in amateur padel ( p = 0.800). The shot frequency is longer in elite padel ( X̅: 0.87) than amateur padel ( X̅: 0.82) and in men padel ( X̅: 0.86) than women padel ( X̅: 0.82), although no significant differences were found. Finally, the player on the right tends to hits the ball less than the player on the left (except women elite players). These results are highly relevant for coaches, as they allow them to guide training processes and quantify the specific workloads of the match based on the gender and level of the players.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"64 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135540127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-05DOI: 10.1177/17479541231206682
Mitchell F Aarons, Will Vickery, Lyndell Bruce, Chris M Young, Dan B Dwyer
Elite sport coaches are often expected to make high-stakes decisions in time-constrained environments, such as during matches. The quality or efficiency of these decisions is bound by context-specific constraints on their decision-making. Artificial intelligence-based tools could alleviate some of these constraints. In Australian football, it is not yet known what these context-specific constraints are, nor is there any understanding of the thoughts and perception of elite Australian football coaches towards the use of artificial intelligence to support their decision-making. This study is the first to explore these issues in the context of elite Australian football and aims to inform the effective design and integration of tools to support the in-match decision-making of coaches in a manner that is welcomed by coaches. Using semi-structured interviews with elite Australian football coaches ( n = 6) and reflexive thematic analysis, two domains were explored: ‘barriers to decision-making’ and ‘thoughts and perceptions of a decision support system (DSS)’. Coaches discussed seven ‘cognitive’ and ‘environmental’ barriers, some of which may be addressed using artificial intelligence. Meanwhile, four themes were generated for the second domain, namely ‘willingness to adopt’, ‘expectation’, ‘concern and criticism’, and ‘DSS role’. The findings enable practitioners to design tools that are intended to address some of these barriers, while also providing insights into important considerations for the implementation and design of these tools that may increase the likelihood of achieving the endorsement of elite coaches and their support staff.
{"title":"Barriers to coach decision-making during Australian football matches and how it can be supported by artificial intelligence","authors":"Mitchell F Aarons, Will Vickery, Lyndell Bruce, Chris M Young, Dan B Dwyer","doi":"10.1177/17479541231206682","DOIUrl":"https://doi.org/10.1177/17479541231206682","url":null,"abstract":"Elite sport coaches are often expected to make high-stakes decisions in time-constrained environments, such as during matches. The quality or efficiency of these decisions is bound by context-specific constraints on their decision-making. Artificial intelligence-based tools could alleviate some of these constraints. In Australian football, it is not yet known what these context-specific constraints are, nor is there any understanding of the thoughts and perception of elite Australian football coaches towards the use of artificial intelligence to support their decision-making. This study is the first to explore these issues in the context of elite Australian football and aims to inform the effective design and integration of tools to support the in-match decision-making of coaches in a manner that is welcomed by coaches. Using semi-structured interviews with elite Australian football coaches ( n = 6) and reflexive thematic analysis, two domains were explored: ‘barriers to decision-making’ and ‘thoughts and perceptions of a decision support system (DSS)’. Coaches discussed seven ‘cognitive’ and ‘environmental’ barriers, some of which may be addressed using artificial intelligence. Meanwhile, four themes were generated for the second domain, namely ‘willingness to adopt’, ‘expectation’, ‘concern and criticism’, and ‘DSS role’. The findings enable practitioners to design tools that are intended to address some of these barriers, while also providing insights into important considerations for the implementation and design of these tools that may increase the likelihood of achieving the endorsement of elite coaches and their support staff.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"57 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135725968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-30DOI: 10.1177/17479541231205473
Sam Barraclough, David Piggott, Kevin Till, Adam Kerr, Stacey Emmonds
Important decisions surrounding talent identification (TID), talent development (TD) and (de)selection within elite youth soccer are often grounded in the subjective opinions of coaches. These opinions often stem from coaches’ observations of player performance, which have been shown to be susceptible to several biases. Additionally, previous research has failed to establish specific criteria on which such opinions are based, aside from a coach's own intuition and practical experience. This study aimed to create a communal language and aligned criteria for the specific purpose of evaluating players’ performances. Semi-structured interviews were undertaken with nine experienced coaches (13.6 ± 10.8 years) from a professional UK soccer academy to identify coaches’ perceptions of key position-specific soccer actions, performed during differing moments of the game, for evaluating individual match performance. Thematic analysis of the interview data permitted the extraction of several themes , posited to encompass the position-specific soccer actions highlighted by the coaches. Themes for outfield positions included attacking skills; defending skills; movements to receive, create or exploit space; receiving and releasing skills; support play; end product; press, recover to the ball, man or space; and tactical understanding. Goalkeeper themes included tactical understanding, positioning relative to the ball, danger, teammates and opponents, play forward, support play, choice of action and range of distribution. This study highlights an applied approach of creating a shared mental model for appraising player performances, which can facilitate discussion and knowledge exchange between coaches and practitioners, with the intention of improving decision-making around TID, TD and (de)selection decisions.
{"title":"Creating a shared mental model of performance: Coaches’ perspectives of key position-specific soccer actions","authors":"Sam Barraclough, David Piggott, Kevin Till, Adam Kerr, Stacey Emmonds","doi":"10.1177/17479541231205473","DOIUrl":"https://doi.org/10.1177/17479541231205473","url":null,"abstract":"Important decisions surrounding talent identification (TID), talent development (TD) and (de)selection within elite youth soccer are often grounded in the subjective opinions of coaches. These opinions often stem from coaches’ observations of player performance, which have been shown to be susceptible to several biases. Additionally, previous research has failed to establish specific criteria on which such opinions are based, aside from a coach's own intuition and practical experience. This study aimed to create a communal language and aligned criteria for the specific purpose of evaluating players’ performances. Semi-structured interviews were undertaken with nine experienced coaches (13.6 ± 10.8 years) from a professional UK soccer academy to identify coaches’ perceptions of key position-specific soccer actions, performed during differing moments of the game, for evaluating individual match performance. Thematic analysis of the interview data permitted the extraction of several themes , posited to encompass the position-specific soccer actions highlighted by the coaches. Themes for outfield positions included attacking skills; defending skills; movements to receive, create or exploit space; receiving and releasing skills; support play; end product; press, recover to the ball, man or space; and tactical understanding. Goalkeeper themes included tactical understanding, positioning relative to the ball, danger, teammates and opponents, play forward, support play, choice of action and range of distribution. This study highlights an applied approach of creating a shared mental model for appraising player performances, which can facilitate discussion and knowledge exchange between coaches and practitioners, with the intention of improving decision-making around TID, TD and (de)selection decisions.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":"98-100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136068115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：