{"title":"Inter-joint coordination variability decreases during dual-task treadmill running.","authors":"Hsiang-Ling Teng, Jo Armour Smith","doi":"10.1080/14763141.2025.2557401","DOIUrl":"https://doi.org/10.1080/14763141.2025.2557401","url":null,"abstract":"<p><p>This study examined the effects of dual-task (DT) running on lower extremity and trunk coordination variability and whether these effects differed across running speeds. Thirty-one asymptomatic recreational runners (18 males, 13 females; age 26.2 ± 6.9 years; BMI 23.6 ± 2.8 kg/m²) completed treadmill running trials under three task conditions: single-task (ST), DT withan easy cognitive task (DT-easy), and DT with a difficult cognitive task (DT-hard). Each condition included three speeds: 85%, 100%, and 115% of preferred speed. Coordination variability of lower extremity joints and trunk segments during stance was quantified using Vector Coding and Ellipse Area methods. Two-way repeated-measures ANOVAs showed significant main effects of task (<i>p</i> < 0.05), with lower coordination variability observed under DT-hard compared to ST conditions. Speed effects were also significant, with greater variability at slower speeds. No significant task-by-speed interactions were found, indicating that DT effects were consistent across speeds. These findings suggest runners exhibit reduced movement adaptability under cognitively demanding DT conditions. Evaluation and training protocols for runners may benefit from incorporating DT paradigms to better reflect real-world demands.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-19"},"PeriodicalIF":2.0,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145330740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A case study on the classification of somersault jumping motion characteristics in trampoline gymnasts using the TJ-index.","authors":"Masaharu Matsushima","doi":"10.1080/14763141.2025.2572769","DOIUrl":"https://doi.org/10.1080/14763141.2025.2572769","url":null,"abstract":"<p><p>The purpose of this study was to propose the TJ-index, which uses deflection distance and contact time as variables, as an index of somersault jumps in trampoline competitions, and to clarify the characteristics of the jumping motion of trampoline gymnasts as a case study. Ten participants, ranging from elite trampoline gymnasts to those at the national competition level, performed 10 consecutive backward somersaults and forward somersault half-twists in alternating sequence. A strong positive correlation was observed between the TJ-index and time of flight (<i>r</i> = 0.98, <i>p</i> < 0.01). The relationship between deflection distance and contact time, which together constitute the TJ-index, was classified into six types using Ward's cluster analysis method. Moreover, normalising deflection distance by body mass revealed individual jump characteristics. The bed's deflection distance may primarily result from either the gymnast's body mass or their active jumping motion. A strong negative correlation was observed between deflection distance per unit of body mass and contact time (<i>r</i> = -0.87, <i>p</i> < 0.01). These findings suggested the existence of body mass optimisation in trampoline gymnasts. The use of the TJ-index appears to have potential for identifying and classifying the jumping motion tendencies of trampoline gymnasts by type.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-14"},"PeriodicalIF":2.0,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145304321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jasper Wong, Hannah E Wyatt, Chris Whatman, Matt R Cross, Danielle Yang, Kelly Sheerin
{"title":"Evaluating agreement between a high-g and low-g accelerometer for measuring tibial acceleration across a range of running velocities.","authors":"Jasper Wong, Hannah E Wyatt, Chris Whatman, Matt R Cross, Danielle Yang, Kelly Sheerin","doi":"10.1080/14763141.2025.2569582","DOIUrl":"https://doi.org/10.1080/14763141.2025.2569582","url":null,"abstract":"<p><p>Modern inertial measurement units house multiple accelerometers with differing specifications. Previous studies have used both high-g and low-g accelerometers to measure peak tibial acceleration (TA) during running. This dual approach may introduce inconsistencies with data processing due to the different specifications. The purpose of this study was to evaluate the agreement between the high-g and low-g accelerometers in measuring peak axial and resultant TA across a range of running velocities. One hundred recreational runners ran on an athletics track at five self-selected velocities, ranging from very slow to very fast based on their comfortable training pace. Results indicated the difference in agreement between the high-g and low-g accelerometers was curvilinear, with bias shifting towards the high-g accelerometer at higher TA magnitudes. However, the predicted difference was small, only exceeding ±1 g when measuring axial TA approaching its maximum range (16 g). Based on the comparable performance of the high-g and low-g accelerometers, and the relatively high frequency of data clipping in the low-g accelerometer (209 of 495 trials; 42%), it is recommended to use the high-g accelerometer exclusively for measuring TA during running, simplifying data collection and processing requirements.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-13"},"PeriodicalIF":2.0,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145276475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oussama Jlassi, Ethan W C Wilkie, Matthew Kelly, Philippe J Renaud, David J Pearsall, Shawn M Robbins, Philippe C Dixon
{"title":"Machine learning-based classification of ice hockey skating tasks using kinematic data.","authors":"Oussama Jlassi, Ethan W C Wilkie, Matthew Kelly, Philippe J Renaud, David J Pearsall, Shawn M Robbins, Philippe C Dixon","doi":"10.1080/14763141.2025.2569580","DOIUrl":"https://doi.org/10.1080/14763141.2025.2569580","url":null,"abstract":"<p><p>This study evaluates the ability of body segment kinematic data to identify skating tasks in ice hockey using machine learning models and compares the performance of models trained on different body segments. We employed XGBoost, Support Vector Machine and Random Forest models to classify four primary ice-hockey skating tasks: forward skating start and strides, skating stop & go, and skating into a wrist shot. Trunk, pelvis, thigh, shank, and foot segment centre of mass linear accelerations were derived from retro-reflective markers and used as inputs for feature engineering. The models were trained and evaluated using a 10-fold cross-validation stratified by participant. Overall, the machine learning models demonstrated strong performance, with mean accuracy scores ranging from 86.5% to 98.9%. The pelvis yielded the best overall performance, followed by the trunk and foot, whereas the thigh segment generally exhibited lower accuracies across models. These results indicate that prediction performance depends on the body segment kinematic data used as input. This study highlights the potential of body segment kinematic data for automated identification of ice hockey skating tasks, providing insights into sports analytics and player performance assessment.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-14"},"PeriodicalIF":2.0,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145253565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Training junior tennis players to increase knee flexion improves their service performance.","authors":"Joana Ferreira Hornestam, Thales Rezende Souza, Fabrício Anício Magalhães, Mickäel Begon, Bruce Elliott, Sérgio Teixeira Fonseca","doi":"10.1080/14763141.2025.2568220","DOIUrl":"https://doi.org/10.1080/14763141.2025.2568220","url":null,"abstract":"<p><p>This study aimed to assess whether training to increase knee flexion during the tennis serve improves performance and to explore the associated biomechanical changes across the body. Twenty junior tennis players were randomly allocated into control (standard in-season training) and training groups (received training to increase knee flexion during serve). Inertial sensors tracked full body and racket kinematics during five serves performed in pre- and post-training assessments. Racket velocity, impact height, and lower- and upper-body kinematics were compared. Training increased serve knee flexion by 31° (<i>p</i> < 0.001), leading to a 1.38 km/h increase racket velocity (<i>p</i> = 0.036) without affecting impact height (<i>p</i> = 0.331). Additionally, training increased: range of front leg knee extension (MD = 23.46°, <i>p</i> < 0.001) and extension velocity (MD = 54.28°/s, <i>p</i> = 0.008), hip range of motion (front: MD = 53.60°/s, <i>p</i> = 0.003; back: MD = 57.28°/s, <i>p</i> = 0.015), pelvis upward velocity (MD = 0.27 m/s, <i>p</i> < 0.001), and trunk contralateral flexion velocity (MD = 23.18°/s, <i>p</i> = 0.025). No main effects were found for shoulder internal rotation (<i>p</i> = 0.304) and elbow extension (<i>p</i> = 0.214) velocities. No changes were observed in the control group other than a decreased trunk contralateral flexion velocity (MD = -28.98°/s, <i>p</i> = 0.007). Specific training can, therefore, increase serve knee flexion. This study highlights that specific training to increase knee flexion can enhance serve performance by increasing racket velocity, without increasing upper limb joint contribution.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-16"},"PeriodicalIF":2.0,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145253513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael J Hiley, Paul Hall, Maurice R Yeadon, Gareth Irwin
{"title":"Application of the coaching biomechanics interface: which technique should I choose?","authors":"Michael J Hiley, Paul Hall, Maurice R Yeadon, Gareth Irwin","doi":"10.1080/14763141.2025.2552179","DOIUrl":"https://doi.org/10.1080/14763141.2025.2552179","url":null,"abstract":"<p><p>The undersomersault (Felge) is one of the key family of skills on the parallel bars in men's artistic gymnastics. At the highest level of competition, two distinct techniques, termed here 'deep pike' and 'hips close', are used to perform the skill. The aim of the present study was to determine the relative performance benefits of each technique in order to provide coaches with information to facilitate technique selection and gymnast preparation. A combination of kinematic analysis of Olympic performances and technique optimisation using computer simulation modelling was used to address this aim. The kinematic analysis found that both techniques had similar performance outcomes in terms of generating horizontal and vertical velocity at release, confirming that both techniques were fit for purpose. Results from the optimisation study found that the 'deep pike' had an advantage in generating vertical velocity, due to more time to perform work, and being more forgiving in terms of generating a larger release window for acceptable performance, whilst the 'hips close' technique was associated with requiring less effort (sum of joint torques squared). As the 'deep pike' requires more effort and a larger range of hip flexibility, choosing this technique will have implications for gymnast preparation.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-17"},"PeriodicalIF":2.0,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145245595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Biomechanical analysis of the knee joint during sidestepping: a fully immersive virtual reality approach to football defending scenarios.","authors":"Andy Man Kit Lei, Kuangyou Bruce Cheng","doi":"10.1080/14763141.2025.2568217","DOIUrl":"https://doi.org/10.1080/14763141.2025.2568217","url":null,"abstract":"<p><p>Traditional sidestepping experiment often relies on simplified visual stimuli that lack ecological validity. This study aimed to develop a fully immersive, football-specific virtual reality (VR) system to examine knee biomechanics during sidestepping in response to realistic visual stimuli. Twelve male collegiate footballers performed unanticipated sidestepping in response to a virtual footballer avatar executing either non-deceptive (VF-ND) or deceptive (VF-D) dribbling. Despite similar approach velocity and stance time, participants exhibited greater knee flexion angles and abduction and internal rotation moments in VF-D trials. Secondary analyses compared the results with previously reported arrow-preplanned (A-PP) and arrow-unplanned (A-UP) trials from the same participants. Approaching velocity decreased, and stance time increased in the following order: A-PP, VF-ND, VF-D and A-UP. Knee flexion angles and abduction moments increased, while peak internal rotation moments decreased in the same order. These findings suggested that the VR-based approach imposed more realistic visuospatial and temporal constraints than traditional methods, enhancing ecological validity. As in real environment, players in VR can perceive subtle cues, distinguish deceptive from non-deceptive actions and adapt their movements accordingly. Practitioners should design their protocols to resemble real-world scenarios as closely as possible and interpret the biomechanical outcomes cautiously when comparing across different visual stimuli.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-22"},"PeriodicalIF":2.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145234202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
André V Brito, Diogo Carvalho, Mayara Silva, Francisco Ferreira, João Paulo Vilas-Boas, Jaime Fernandez-Fernandez, Ricardo J Fernandes
{"title":"The effect of a prolonged tennis serve game on shoulder function, speed and precision.","authors":"André V Brito, Diogo Carvalho, Mayara Silva, Francisco Ferreira, João Paulo Vilas-Boas, Jaime Fernandez-Fernandez, Ricardo J Fernandes","doi":"10.1080/14763141.2025.2552172","DOIUrl":"https://doi.org/10.1080/14763141.2025.2552172","url":null,"abstract":"<p><p>Due to the constant high physical strain on tennis players during a match, the effect of a prolonged serve game on torque, power and work of the shoulder external and internal rotations, as well as on serve speed and precision, was investigated. Eighteen male competitive tennis players performed shoulder external and internal rotations (90º of abduction) at 180 and 300º/s on an isokinetic dynamometer before and after 12 points with one flat serve plus forehands and simulated backhands. When comparing pre and post moments, torque and power decreased in external (0.41 ± 0.07 vs 0.39 ± 0.06 N.m/kg and 71.1 ± 27.3 vs 59.7 ± 27.1 W) and internal (0.54 ± 0.10 vs 0.50 ± 0.13 N.m/kg and 91.7 ± 30.7 vs 80.1 ± 38.1 W) rotations at 300º/s, with <i>p</i> ≤ 0.05. Serve speed decreased after the fifth and sixth point (142.0 ± 20.1 vs 132.5 ± 15.3 km/h) and between clusters 1-6 and 7-12 (141.7 ± 15.5 vs 134.9 ± 12.4 km/h), with <i>p</i> ≤ 0.01. Serve precision decreased at the fifth and eighth points, with the highest score recorded at the end of the game. Training should focus on improving players ability to maintain performance during consecutive points, enhancing technical proficiency.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-20"},"PeriodicalIF":2.0,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145201886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Seyyed Hadi Asghari, Alexei Wong, Paul Comfort, Seyed Javad Mirghani, Shohreh Sharifian, Mahbanou Ghaderi
{"title":"Comparing the impact of hip thrust versus squat training on lower limb performance in sub-elite athletes: a systematic review and meta-analysis.","authors":"Seyyed Hadi Asghari, Alexei Wong, Paul Comfort, Seyed Javad Mirghani, Shohreh Sharifian, Mahbanou Ghaderi","doi":"10.1080/14763141.2025.2553700","DOIUrl":"https://doi.org/10.1080/14763141.2025.2553700","url":null,"abstract":"<p><p>The aim of this systematic review and meta-analysis was to compare the effects of squat (SQ) and hip thrust (HT) training on performance in lower body athletic tasks, across different groups. A comprehensive search was conducted up to 31 May 2024, using PubMed, Web of Science, Scopus, Google Scholar, and Embase. SQ training was found to significantly improve vertical jump height (VJH) but greater than the HT. Neither SQ nor HT training had a significant impact on horizontal jump distance (HJD), short sprint time (SST), short sprint performance (SSP) or change of direction (COD) performance. In 12 to 16 sessions subgroup, SQ training significantly improved VJH, showing a medium ES. However, in other subgroups, neither SQ nor HT exercises produced significant improvements in HJD, SSP, SST, or COD performance. Subgroup analyses corroborated these findings. Squat exercises are more effective in developing VJH, while alternatively, no conclusive preference can be made between the exercises for enhancing HJD, SSP, and SST markers. Neither exercise had a discernible impact on COD performance. Future research should focus on conducting higher-quality studies to better elucidate the specific effects of SQ and HT training, or a combination of the two exercises, on various performance metrics.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-20"},"PeriodicalIF":2.0,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145132258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J Freeston, S G J Hardy, E Ho, P Sinclair, S Chalmers, M Hollings, J T Andersen
{"title":"Accuracy of a bat-mounted sensor for the measurement of bat speed among elite female cricket players.","authors":"J Freeston, S G J Hardy, E Ho, P Sinclair, S Chalmers, M Hollings, J T Andersen","doi":"10.1080/14763141.2025.2549136","DOIUrl":"https://doi.org/10.1080/14763141.2025.2549136","url":null,"abstract":"<p><p>Currently, there are no validated field-based measures of bat speed in cricket. This study sought to validate a baseball bat-mounted sensor for use in cricketers. Nine professional female cricketers (19.9 ± 2.8 years, 166.6 ± 4.8 cm, 68.7 ± 8.6 kg) performed 40 swings across four shot types (Cut, Drive, Pull, Slog-Sweep). Bat speed from a bat-mounted sensor was compared to optical motion capture (MoCap). Bat speed differed between shot types and ranged from 52.8 to 87.9 km/h. Device accuracy was determined by Bland-Altman bias and precision. The Drive shot had the smallest bias (-1.0 km/h; 1.4%), followed by the Slog-Sweep (2.0 km/h; 2.7%), Pull (2.0 km/h; 2.8%) then Cut shot, (2.5 km/h; 3.9%). The Cut shot had the greatest precision (2.7 km/h; 4.1%), followed by Pull (3.4 km/h; 4.7%), Slog-Sweep (4.0 km/h; 5.3%) and Drive (4.4 km/h; 6.3%). Kendall's tau analysis showed that proportional errors increased with higher bat speeds for all shots except Pull, (<i>p</i> < 0.05). The evidence supports use of the sensor for bat speed among female cricket players for all shots between speeds of 52.8-87.9 km/h. Caution is warranted for additional shot types, and speeds outside the explored range.</p>","PeriodicalId":49482,"journal":{"name":"Sports Biomechanics","volume":" ","pages":"1-12"},"PeriodicalIF":2.0,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145114818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}