International Journal of Sports Science & Coaching最新文献

{"title":"Wearable technology metrics are associated with energy deficiency and psychological stress in elite swimmers","authors":"Emily A. Lundstrom, Mary Jane De Souza, Kristen J. Koltun, Nicole C.A. Strock, Hannah N. Canil, Nancy I. Williams","doi":"10.1177/17479541231206424","DOIUrl":"https://doi.org/10.1177/17479541231206424","url":null,"abstract":"Energy deficiency (ED) and psychological stress affect athlete health. Given the emerging capabilities of wearable technology, the purpose of this study was to explore associations of wearable technology metrics in relation to lab-based measures of ED and psychological stress. We investigated the associations between (a) wearable-derived heart rate variability (HRV), resting heart rate (RHR), exercise strain and recovery, and (b) laboratory-derived measures of metabolism (resting metabolic rate (RMR), total triiodothyronine (TT 3 )) and a validated stress assessment (Recovery-Stress Questionnaire for Athletes (RESTQ)-52 items) in NCAA swimmers ( n = 23, 10 male, 13 female) during heavy training. Swimmers were grouped by degree of metabolic adaption to ED using the ratio of actual-to-predicted RMR (utilizing the validated cutoff of <0.94) and by sex. Metabolically suppressed swimmers had lower HRV (81 ± 27 ms vs.110 ± 35 ms, p = 0.04). HRV correlated positively with RMR (kcal·kg LBM −1 ·day −1 ; where LBM stands for lean body mass) ( r = 0.45; p = 0.03). HRV was negatively correlated with sport-specific ( r = −0.46; p = 0.03) and total stress ( r = −0.46; p = 0.03). In males, HRV correlated negatively with general stress ( r = −0.72; p = 0.02) and total stress ( r = −0.74, p = 0.01) (RESTQ). Additionally, in males only, the strain was correlated positively with RESTQ recovery–stress balance ( r = 0.69; p = 0.03), and negatively correlated with general stress ( r = −0.81, p = 0.01), and sport stress ( r = −0.89, p < 0.01). No correlations between HRV, RHR, strain or recovery, and stress variables were observed in females. Associations between wearable technology measures of HRV, RHR, strain, and recovery with validated measures of ED and psychological stress should continue to be explored with a focus on underlying mechanisms and moderating influences of biological sex.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135414772","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}

{"title":"The pre-match talk: A multiple-method examination of youth-elite football coaches’ motivational content","authors":"Pablo E Raya-Castellano, Tomás García-Calvo, Miguel A López-Gajardo, Joaquín Martín Marzano-Felisatti, Juan J Pulido","doi":"10.1177/17479541231207254","DOIUrl":"https://doi.org/10.1177/17479541231207254","url":null,"abstract":"Pre-match meetings are popular scenes in team sports, with coaches typically gathering the full squad within the dressing room and sharing their thoughts before the warm-up and/or competition. Whilst researchers have outlined the effects of informational or emotional talks, little is known about the actual verbal strategies that coaches adopt to influence their players. Therefore, this study examined the motivational content of football coaches’ verbal behaviours and underpinning perceptions of pre-match talks’ delivery. Five coaches ( M age = 36.2 years) working at a La Liga academy were involved in six pre-match talks ( n = 30) and one semi-structured interview each. Talks were analysed using a two-stage coding process after adaptation of validated and motivationally relevant instruments, and interviews were assessed following thematic analysis procedures. Game strategy units were the most commonly employed topic across all coaches, which involved ‘neutral’ behaviours such as role description, game objective specification, and opposition statements. These were complemented with autonomy and competence supportive messages such as facilitating choices/opinions, offering rationales, supporting past performance, or ego-oriented and social climate support dimensions, depending on the coach. Data suggested that contextual factors could strengthen or attenuate the use of these verbal behaviours/dimensions. Build-up play contents were more likely to feature autonomy support game strategy comments than defending aspects, whereas lower-ranked and underdog opponents were associated with increased disapproving past performance and ego-involving statements compared to when facing higher-ranked opponents or playing derbies. Thus, it is suggested that the use of autonomy-, competence- and relatedness-supportive dimensions in addition to task-oriented messages should be reconsider by coaches if attempting to convey a need-supportive motivational climate.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135969579","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}

{"title":"Comprehensive preparation strategies for a world-class endurance athlete competing in major international competitions in hot environmental conditions: A case study","authors":"Amelia J Carr, Avish P Sharma, Megan LR Ross, Brent S Vallance","doi":"10.1177/17479541231194126","DOIUrl":"https://doi.org/10.1177/17479541231194126","url":null,"abstract":"Purpose To document a world-class race walking athlete's preparation for the 2019 International Association of Athletics Federations (IAAF) World Championships (Doha, Qatar), including periodized training, physiological data, cooling strategies and nutritional practices. Methods Physiological data (VO 2max , mL·kg −1 ·min −1 ; submaximal economy, mL·kg −1 ·min −1 ; and %VO 2max ), training volume (km) and intensity (min·km −1 ) were recorded (January–May 2019). Additional training strategies and interventions (altitude training, heat acclimation/acclimatization, cooling methods and pre- and during-race nutrition) were described (February–October 2019). Performances in IAAF-sanctioned 20 km races were also reported. Results The athlete's highest VO 2max result was 74.6 mL·kg −1 ·min −1 , and his highest 4 mmol·L −1 walking speed was 15.7 km·h −1 . The best submaximal economy measures (the lowest proportional oxygen use at 13 km·h −1 ) were 48.4 mL·kg −1 ·min −1 (65.2% VO 2max ). The best performance outcome was a bronze medal-winning performance at the 2019 IAAF World Championships (32°C; 77% RH). Six blocks of altitude training were performed (119 days). Five blocks of heat acclimatization training (127 days), one block of heat acclimation training (8 days) and two blocks of post-training passive heat sessions (16 days) were completed. Internal and external cooling strategies were used, and the athlete's nutritional intake focused on carbohydrate and fluid intake prior to and during races, pre-race supplementation with sodium bicarbonate using chronic and acute protocols, caffeine supplementation during races and pre-race hyperhydration. Conclusion The strategies used by this elite athlete included repeated heat acclimation, heat acclimatization, passive heat exposure, hypoxic training and heat mitigation strategies. Similar strategies may provide benefit to elite athletes preparing for major international competitions in hot conditions.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135095481","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}

{"title":"Integration of golf practise and strength and conditioning in golf: Insights from professional golf coaches","authors":"Alex Bliss, Ben Langdown","doi":"10.1177/17479541231199657","DOIUrl":"https://doi.org/10.1177/17479541231199657","url":null,"abstract":"Strength and conditioning (S&amp;C) interventions for golfers consistently demonstrate improvements in performance metrics such as clubhead speed. Golfers typically employ Professional Golfers’ Association (PGA) coaches to support technical and tactical development. These coaches need to ensure golfers balance S&amp;C training alongside competitions and technical golf practise, although no empirical data exist that demonstrates how this integration occurs practically. This study aimed to investigate the perceptions and practises of PGA Professional golf coaches and how S&amp;C is integrated into the golf year. Forty-three (male = 35; female = 8) PGA coaches completed a mixed-methods survey with questions on themes such as coaching approach, perceptions of S&amp;C, annual planning and goal setting. Results show that formal planning processes are highly variable or absent. The majority (n = 29; 70.7%) of PGA coaches stated they worked with an S&amp;C coach and see the role of the S&amp;C coach to support golfers with their input. However, when planning the season, 63.4% (n = 26) of coaches do so without input from the S&amp;C coach. These and other related disconnects between desire for S&amp;C intervention and inclusion of the S&amp;C coach in planning processes were evident throughout survey responses. There may be subsequent risks of conflict or misunderstanding between PGA coach, S&amp;C coach and golfer. It is recommended golf coaches, golfers and S&amp;C coaches work collaboratively as a multidisciplinary support team to ensure coordinated golfer support is obtained.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134944291","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}

{"title":"Does game-based training replicate match inside-50 entries in elite Australian Rules football?","authors":"Olivia Wallace, Will Vickery, Lyndell Bruce","doi":"10.1177/17479541231204114","DOIUrl":"https://doi.org/10.1177/17479541231204114","url":null,"abstract":"The purpose of this research was to determine if the training design of an elite Australian Rules football team replicated match conditions for inside-50 entries. Notational analyses of one professional Australian Rules football club's training and match footage were conducted for every disposal that entered the inside-50 during either game-based training or matches. Analysed variables included how the ball was received, time in possession and location. Statistical analyses were undertaken using Mann–Whitney tests, a multivariate analysis of variance and a decision tree analysis. Significant differences were identified between game-based training and competition matches for 34 of the 54 inside-50 entry variables. Of these 34 variables, 10 showed a strong effect between session types. When examining the efficiency of inside-50 entries, only effective disposals produced a significant difference between training and matches, with no differences for neutral and ineffective disposals. The session type, how the ball was received, decision (e.g., kick vs. handball) and pressure acts were the most important contributors to effective inside-50 entry disposal efficiency. The results suggest this professional Australian Rules team does not participate in training sessions that reflect inside-50 match conditions. This study may provide a framework for elite Australian Rules teams on which to structure their inside-50 training.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135352633","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}

{"title":"An investigation of data-driven player positional roles within the Australian Football League Women's competition using technical skill match-play data","authors":"Braedan van der Vegt, Adrian Gepp, Justin Keogh, Jessica B. Farley","doi":"10.1177/17479541231203895","DOIUrl":"https://doi.org/10.1177/17479541231203895","url":null,"abstract":"Understanding player positional roles are important for match-play tactics, player recruitment, talent identification, and development by providing a greater understanding of what each positional role constitutes. Currently, no analysis of competition technical skill data exists by player position in the Australian Football League Women's (AFLW) competition. The primary aim of the research was to use data-driven techniques to observe what positions and roles characterise AFLW match-play using detailed technical skill action data of players. A secondary aim was to comment on the application of clustering methods to achieve more interpretable, reflective positional clustering. A two-stage, unsupervised clustering approach was applied to meet these aims. Data cleaning resulted in 165 variables across 1296 player seasons in the 2019–2022 AFLW seasons which was used for clustering. First-stage clustering found four positions following a common convention (forwards, midfielders, defenders, and rucks). Second-stage clustering found roles within positions, resulting in a further 13 clusters with three forwards, three midfielders, four defenders, and three ruck positional roles. Key variables across all positions and roles included the field location of actions, number of contested possessions, clearances, interceptions, hitouts, inside 50s, and rebound 50s. Unsupervised clustering allowed the discovery of new roles rather than being constrained to pre-defined existing classifications of previous literature. This research assists coaches and practitioners by identifying key game actions players need to perform in match-play by position, which can assist in player recruitment, player development, and identifying appropriate match-play styles and tactics, while also defining new roles and suggestions of how to best use available data.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134974996","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}

{"title":"Feasibility and acceptability of a new shoulder-specific warm-up programme to prevent injuries in community youth rugby union as compared to the FIFA 11+","authors":"Vincent R. Singh, Keith Stokes, Carly D. Mckay","doi":"10.1177/17479541231192170","DOIUrl":"https://doi.org/10.1177/17479541231192170","url":null,"abstract":"Injury prevention exercise programmes (IPEPs) are efficacious, though there is no IPEP specifically designed to reduce shoulder injuries in rugby. This study aimed to determine the feasibility and acceptability of the Rugby Active Shoulder Injury Prevention (RASIP) programme. Three community rugby union clubs participated in a 12-week pilot study (players, n = 51; coaches, n = 7). Two teams were randomly allocated to the RASIP programme and one to the FIFA 11+ (IPEP) intervention. Feasibility was examined by players’ adherence to the IPEP, and acceptability was described by players’ and coaches’ perceptions of the IPEP. On average, more players were exposed to 11+ training sessions (100%) than the RASIP programme (19 out of 36 players, 53%). Higher percentage of exercises was completed over the season in the 11+ (97%) than the RASIP programme (58%). Across both groups, there were different approaches followed in delivering the allocated intervention. The coach-led, prescriptively followed 11+ IPEP was better at achieving higher adherence with exercises. Coaches were concerned of not having enough time in their sessions to include the IPEP. This pilot study has shown that the intervention is feasible to deliver and is acceptable with improvements recommended by community stakeholders, coaches and players in a community youth rugby setting.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136308025","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}

{"title":"Importance of fundamental movement skills to predict technical skills in youth grassroots soccer: A machine learning approach","authors":"Michael J. Duncan, Emma L. J. Eyre, Neil Clarke, Abdul Hamid, Yanguo Jing","doi":"10.1177/17479541231202015","DOIUrl":"https://doi.org/10.1177/17479541231202015","url":null,"abstract":"This study determined the contributors to soccer technical skills in grassroots youth soccer players using a machine learning approach. One hundred and sixty-two boys aged 7 to 14 (mean ± SD = 10.5 ± 2.1) years, who were regularly engaged in grassroots soccer undertook assessments of anthropometry and maturity offset (the time from age at peak height velocity (APHV)), fundamental movement skills (FMS), perceived physical competence, and physical fitness and technical soccer skill using the University of Ghent dribbling test. Coaches rated player's overall soccer skills for their age. Statistical analysis was undertaken, using machine learning models to predict technical skills from the other variables. A stepwise recursive feature elimination with a 5-fold cross-validation method was used to eliminate the worst-performing features and both L1 and L2 regularisation were evaluated during the process. Five models (linear, ridge, lasso, random forest, and boosted trees) were then used in a heuristic approach using a small subset of suitable algorithms to achieve a reasonable level of accuracy within a reasonable time frame to make predictions and compare them to a test set to understand the predictive capabilities of the models. Results from the machine learning analysis indicated that the total FMS score (0 to 50) was the most important feature in predicting technical soccer skills followed by coach rating of child skills for their age, years of playing experience and APHV. Using a random forest, technical skills could be predicted with 99% accuracy in boys who play grassroots soccer, with FMS being the most important contributor.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135016244","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}

{"title":"Talent development in childhood: Early specialization or sampling? From an either… or… question to a 2 × 2 × 3 question cuboid","authors":"Bryan Charbonnet, Achim Conzelmann","doi":"10.1177/17479541231197225","DOIUrl":"https://doi.org/10.1177/17479541231197225","url":null,"abstract":"A central, yet still unresolved, question about optimal youth talent development asks whether children should specialize and train systematically in one sport— early specialization—or gain different playful experiences in several sports— early sampling. Based upon theoretical considerations, we problematize dichotomous discussions and offer a complex 2 × 2 × 3 question cuboid differentiating between two goals (performance in adulthood and positive youth development), two continuum-based dimensions (task-specificity and exercise mode), and three perspectives (nomothetic, group-specific, and idiographic). Accordingly, resolving the question about optimal youth talent development involves assembling answers derived from 12 different questions. Through our theoretical contribution, we identified several nomothetic principles offering stakeholders initial recommendations and orientations to estimate the appropriate need for high task-specificity and exercise mode in relation to each goal. We suggest adapting these recommendations according to group-specific characteristics, such as sport and age, and idiographic fine-tuning according to children's biopsychosocial characteristics.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135061245","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}

{"title":"Analysing match-related performance indicators in Super Rugby Competitions: A study of the 2017–2019 seasons","authors":"Mark Nicholls, Derik Coetzee, Robert Schall, Wilbur Kraak","doi":"10.1177/17479541231198211","DOIUrl":"https://doi.org/10.1177/17479541231198211","url":null,"abstract":"Understanding the factors that contribute to success or failure in Super Rugby is paramount for teams aiming to achieve positive results. This study compares winning and losing teams by analysing match-related performance indicators from 2017 to 2019, offering valuable insights for coaches, players, and performance analysts. Significantly, winning teams exhibited notable disparities in their attacking play, surpassing losing teams in total tries (4.5 vs. 2.4), offloads (12.5 vs. 11.2), number of kicks (22.2 vs. 19.4), and line breaks (3.1 vs. 2.2) ( p < .0001 for all). Moreover, defensive performance emerged as a crucial factor, with winning teams demonstrating higher tackle completion rates (89.3 vs. 87.9) ( p < .0001) and an increased number of breakdown turnovers won (0.8 vs. 0.6) ( p = .0518) compared to losing teams. These findings illuminate distinct performance characteristics that can assist coaches, players, and analysts in optimising tactical analysis, player development, and overall performance. Despite the COVID-19 disruption in 2020 and teams transitioning to other competitions, the research remains relevant due to the expected persistence of fundamental game aspects and performance indicators. This adaptability enables informed decision-making, leading to improved performance and a competitive advantage in the current Super Rugby competition.","PeriodicalId":47767,"journal":{"name":"International Journal of Sports Science & Coaching","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134970533","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}