Gregory Roe, Thomas Sawczuk, James Tooby, Sam Hudson, Ryan White, Lois Mackay, Cameron Owen, Lindsay Starling, Matt Cross, Éanna Falvey, Sharief Hendricks, Simon Kemp, Karen Rasmussen, Clint Readhead, Danielle Salmon, Keith Stokes, Ross Tucker, Ben Jones
The aim of this study was to investigate the difference in head acceleration event (HAE) incidence between training and match-play in women's and men's players competing at the highest level of domestic rugby union globally. Players from Women's (Premiership Women's Rugby, Farah Palmer Cup) and Men's (Premiership Rugby, Currie Cup) rugby union competitions wore instrumented mouthguards during matches and training sessions during the 2022/2023 seasons. Peak linear (PLA) and angular (PAA) acceleration were calculated from each HAE and included within generalized linear mixed-effects models. The incidence of HAEs was significantly greater in match-play compared to training for all magnitude thresholds in both forwards and backs, despite players spending approximately 1.75-2.5 times more time in training. For all HAEs (PLA > 5 g and PAA > 400 rad/s2), incidence rate ratios (IRRs) for match versus training ranged from 2.80 (95% CI: 2.38-3.30; men's forwards) to 4.00 (3.31-4.84; women's forwards). At higher magnitude thresholds (PLA > 25 g; PAA > 2000 rad/s2), IRRs ranged from 3.64 (2.02-6.55; PAA > 2000 rad/s2 in men's backs) to 11.70 (6.50-21.08; PAA > 2000 rad/s2 in women's forwards). Similar trends were observed in each competition. Players experienced significantly more HAEs during match-play than training, particularly at higher magnitude thresholds. Where feasible, HAE mitigation strategies may have more scope for HAE reduction if targeted at match-play, particularly where higher magnitude HAEs are the primary concern. However, the number of HAEs associated with different training drills requires exploration to understand if HAEs can be reduced in training, alongside optimizing match performance (e.g., enhancing contact technique).
本研究旨在调查参加全球最高级别国内橄榄球联盟比赛的男女球员在训练和比赛中头部加速度事件 (HAE) 发生率的差异。在 2022/2023 赛季期间，参加女子橄榄球比赛（英超女子橄榄球赛、法拉-帕尔默杯）和男子橄榄球比赛（英超橄榄球赛、库里杯）的球员在比赛和训练期间佩戴了带仪器的护齿。根据每个 HAE 计算出峰值线性加速度 (PLA) 和角加速度 (PAA)，并将其纳入广义线性混合效应模型。就所有幅度阈值而言，前锋和后卫的 HAE 发生率在比赛中明显高于训练中，尽管球员在训练中花费的时间大约是比赛中的 1.75-2.5 倍。对于所有 HAEs（PLA > 5 g 和 PAA > 400 rad/s2），比赛与训练的发生率比（IRRs）从 2.80（95% CI：2.38-3.30；男子前锋）到 4.00（3.31-4.84；女子前锋）不等。在较高幅度阈值（PLA > 25 g；PAA > 2000 rad/s2）下，IRR 从 3.64（2.02-6.55；PAA > 2000 rad/s2，男子前锋）到 11.70（6.50-21.08；PAA > 2000 rad/s2，女子前锋）不等。在每场比赛中都观察到了类似的趋势。球员在比赛中出现的 HAE 明显多于训练中出现的 HAE，尤其是在幅度阈值较高的情况下。在可行的情况下，HAE 缓解策略如果以比赛为目标，可能会有更大的空间来减少 HAE，特别是在以较高幅度的 HAE 为主要关注点的情况下。不过，需要对与不同训练演习相关的 HAE 数量进行探讨，以了解在优化比赛表现（如加强接触技术）的同时，是否可以在训练中减少 HAE。
{"title":"Training and Match-Related Head Acceleration Events in Top Level Domestic Senior Women's and Men's Rugby Union: A Multi-League Instrumented Mouthguard Study.","authors":"Gregory Roe, Thomas Sawczuk, James Tooby, Sam Hudson, Ryan White, Lois Mackay, Cameron Owen, Lindsay Starling, Matt Cross, Éanna Falvey, Sharief Hendricks, Simon Kemp, Karen Rasmussen, Clint Readhead, Danielle Salmon, Keith Stokes, Ross Tucker, Ben Jones","doi":"10.1111/sms.14744","DOIUrl":"https://doi.org/10.1111/sms.14744","url":null,"abstract":"<p><p>The aim of this study was to investigate the difference in head acceleration event (HAE) incidence between training and match-play in women's and men's players competing at the highest level of domestic rugby union globally. Players from Women's (Premiership Women's Rugby, Farah Palmer Cup) and Men's (Premiership Rugby, Currie Cup) rugby union competitions wore instrumented mouthguards during matches and training sessions during the 2022/2023 seasons. Peak linear (PLA) and angular (PAA) acceleration were calculated from each HAE and included within generalized linear mixed-effects models. The incidence of HAEs was significantly greater in match-play compared to training for all magnitude thresholds in both forwards and backs, despite players spending approximately 1.75-2.5 times more time in training. For all HAEs (PLA > 5 g and PAA > 400 rad/s<sup>2</sup>), incidence rate ratios (IRRs) for match versus training ranged from 2.80 (95% CI: 2.38-3.30; men's forwards) to 4.00 (3.31-4.84; women's forwards). At higher magnitude thresholds (PLA > 25 g; PAA > 2000 rad/s<sup>2</sup>), IRRs ranged from 3.64 (2.02-6.55; PAA > 2000 rad/s<sup>2</sup> in men's backs) to 11.70 (6.50-21.08; PAA > 2000 rad/s<sup>2</sup> in women's forwards). Similar trends were observed in each competition. Players experienced significantly more HAEs during match-play than training, particularly at higher magnitude thresholds. Where feasible, HAE mitigation strategies may have more scope for HAE reduction if targeted at match-play, particularly where higher magnitude HAEs are the primary concern. However, the number of HAEs associated with different training drills requires exploration to understand if HAEs can be reduced in training, alongside optimizing match performance (e.g., enhancing contact technique).</p>","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142473781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aim of this study was to investigate the difference in head acceleration event (HAE) incidence between training and match-play in women's and men's players competing at the highest level of domestic rugby union globally. Players from Women's (Premiership Women's Rugby, Farah Palmer Cup) and Men's (Premiership Rugby, Currie Cup) rugby union competitions wore instrumented mouthguards during matches and training sessions during the 2022/2023 seasons. Peak linear (PLA) and angular (PAA) acceleration were calculated from each HAE and included within generalized linear mixed-effects models. The incidence of HAEs was significantly greater in match-play compared to training for all magnitude thresholds in both forwards and backs, despite players spending approximately 1.75-2.5 times more time in training. For all HAEs (PLA > 5 g and PAA > 400 rad/s2), incidence rate ratios (IRRs) for match versus training ranged from 2.80 (95% CI: 2.38-3.30; men's forwards) to 4.00 (3.31-4.84; women's forwards). At higher magnitude thresholds (PLA > 25 g; PAA > 2000 rad/s2), IRRs ranged from 3.64 (2.02-6.55; PAA > 2000 rad/s2 in men's backs) to 11.70 (6.50-21.08; PAA > 2000 rad/s2 in women's forwards). Similar trends were observed in each competition. Players experienced significantly more HAEs during match-play than training, particularly at higher magnitude thresholds. Where feasible, HAE mitigation strategies may have more scope for HAE reduction if targeted at match-play, particularly where higher magnitude HAEs are the primary concern. However, the number of HAEs associated with different training drills requires exploration to understand if HAEs can be reduced in training, alongside optimizing match performance (e.g., enhancing contact technique).
本研究旨在调查参加全球最高级别国内橄榄球联盟比赛的男女球员在训练和比赛中头部加速度事件 (HAE) 发生率的差异。在 2022/2023 赛季期间，参加女子橄榄球比赛（英超女子橄榄球赛、法拉-帕尔默杯）和男子橄榄球比赛（英超橄榄球赛、库里杯）的球员在比赛和训练期间佩戴了带仪器的护齿。根据每个 HAE 计算出峰值线性加速度 (PLA) 和角加速度 (PAA)，并将其纳入广义线性混合效应模型。就所有幅度阈值而言，前锋和后卫的 HAE 发生率在比赛中明显高于训练中，尽管球员在训练中花费的时间大约是比赛中的 1.75-2.5 倍。对于所有 HAEs（PLA > 5 g 和 PAA > 400 rad/s2），比赛与训练的发生率比（IRRs）从 2.80（95% CI：2.38-3.30；男子前锋）到 4.00（3.31-4.84；女子前锋）不等。在较高幅度阈值（PLA > 25 g；PAA > 2000 rad/s2）下，IRR 从 3.64（2.02-6.55；PAA > 2000 rad/s2，男子前锋）到 11.70（6.50-21.08；PAA > 2000 rad/s2，女子前锋）不等。在每场比赛中都观察到了类似的趋势。球员在比赛中出现的 HAE 明显多于训练中出现的 HAE，尤其是在幅度阈值较高的情况下。在可行的情况下，HAE 缓解策略如果以比赛为目标，可能会有更大的空间来减少 HAE，特别是在以较高幅度的 HAE 为主要关注点的情况下。不过，需要对与不同训练演习相关的 HAE 数量进行探讨，以了解在优化比赛表现（如加强接触技术）的同时，是否可以在训练中减少 HAE。
{"title":"Training and Match-Related Head Acceleration Events in Top Level Domestic Senior Women's and Men's Rugby Union: A Multi-League Instrumented Mouthguard Study.","authors":"Gregory Roe,Thomas Sawczuk,James Tooby,Sam Hudson,Ryan White,Lois Mackay,Cameron Owen,Lindsay Starling,Matt Cross,Éanna Falvey,Sharief Hendricks,Simon Kemp,Karen Rasmussen,Clint Readhead,Danielle Salmon,Keith Stokes,Ross Tucker,Ben Jones","doi":"10.1111/sms.14744","DOIUrl":"https://doi.org/10.1111/sms.14744","url":null,"abstract":"The aim of this study was to investigate the difference in head acceleration event (HAE) incidence between training and match-play in women's and men's players competing at the highest level of domestic rugby union globally. Players from Women's (Premiership Women's Rugby, Farah Palmer Cup) and Men's (Premiership Rugby, Currie Cup) rugby union competitions wore instrumented mouthguards during matches and training sessions during the 2022/2023 seasons. Peak linear (PLA) and angular (PAA) acceleration were calculated from each HAE and included within generalized linear mixed-effects models. The incidence of HAEs was significantly greater in match-play compared to training for all magnitude thresholds in both forwards and backs, despite players spending approximately 1.75-2.5 times more time in training. For all HAEs (PLA > 5 g and PAA > 400 rad/s2), incidence rate ratios (IRRs) for match versus training ranged from 2.80 (95% CI: 2.38-3.30; men's forwards) to 4.00 (3.31-4.84; women's forwards). At higher magnitude thresholds (PLA > 25 g; PAA > 2000 rad/s2), IRRs ranged from 3.64 (2.02-6.55; PAA > 2000 rad/s2 in men's backs) to 11.70 (6.50-21.08; PAA > 2000 rad/s2 in women's forwards). Similar trends were observed in each competition. Players experienced significantly more HAEs during match-play than training, particularly at higher magnitude thresholds. Where feasible, HAE mitigation strategies may have more scope for HAE reduction if targeted at match-play, particularly where higher magnitude HAEs are the primary concern. However, the number of HAEs associated with different training drills requires exploration to understand if HAEs can be reduced in training, alongside optimizing match performance (e.g., enhancing contact technique).","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142486317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Bai,Ryan Burns,Conrad Ma,Azilee Curl,Jim Hudziak,William E Copeland
Physical activity (PA) is a critical factor in maintaining mental health, particularly among college students who are vulnerable to stress, anxiety, and mood disturbances. The COVID-19 pandemic introduced unprecedented disruptions to daily routines. The purpose of this cohort study was to examine the longitudinal PA behaviors before and during COVID-19 using device-based assessment in a sample of college students. The participants were a convenience sample of 1-year college students from the University of Vermont Wellness Environment study. A daily survey was distributed to the participants every night on a study app measured three mental health outcomes of mood, anxiety, and stress for 16 weeks. Participants wore Apple Watches to monitor PA. A total of 167 participants completed at least 50% of daily surveys and had 20 days of valid Apple Watch data, which resulted in 11 387 participant-days' of observations. Changes in average daily moderate-to-vigorous physical activity (MVPA) and step counts were examined week-over-week from an 8-week period before COVID to an 8-week period during COVID using cluster-robust piecewise regression (16-weeks total). Linear mixed models examined the association between PA and mental health outcomes, while also examining the moderating influence of COVID phase. Significantly lower MVPA was observed from the end of pre-COVID to start of COVID by -18.2 min/day (p < 0.001) and significantly fewer steps/day was observed from end of pre-COVID to start of COVID by -3277 steps/day (p < 0.001). An MVPA "catch-up" effect was observed as there were small but positive week-over-week improvements during COVID for MVPA (b = 1.32 min/day, p < 0.001). The influence of COVID-19 phases had a notable impact on the relationships between PA/exercise and mental health outcomes. A discernible trend emerged, indicating stronger connections during the COVID period for anxiety and stress compared to the pre-COVID era. Interestingly, the moderating effect of COVID was opposite for mood and exercise. The COVID-19 pandemic led to a dramatic decline in PA among college students, coinciding with a period of heightened stress and anxiety. Despite a slight recovery in PA levels during the pandemic, the strengthened association between exercise and anxiety/stress during this time underscores the vital role of PA in promoting mental health. These findings highlight the importance of implementing behavior change strategies to maintain and promote student wellbeing.
{"title":"Tracking Well-Being: A Comprehensive Analysis of Physical Activity and Mental Health in College Students Across COVID-19 Phases Using Ecological Momentary Assessment.","authors":"Yang Bai,Ryan Burns,Conrad Ma,Azilee Curl,Jim Hudziak,William E Copeland","doi":"10.1111/sms.14738","DOIUrl":"https://doi.org/10.1111/sms.14738","url":null,"abstract":"Physical activity (PA) is a critical factor in maintaining mental health, particularly among college students who are vulnerable to stress, anxiety, and mood disturbances. The COVID-19 pandemic introduced unprecedented disruptions to daily routines. The purpose of this cohort study was to examine the longitudinal PA behaviors before and during COVID-19 using device-based assessment in a sample of college students. The participants were a convenience sample of 1-year college students from the University of Vermont Wellness Environment study. A daily survey was distributed to the participants every night on a study app measured three mental health outcomes of mood, anxiety, and stress for 16 weeks. Participants wore Apple Watches to monitor PA. A total of 167 participants completed at least 50% of daily surveys and had 20 days of valid Apple Watch data, which resulted in 11 387 participant-days' of observations. Changes in average daily moderate-to-vigorous physical activity (MVPA) and step counts were examined week-over-week from an 8-week period before COVID to an 8-week period during COVID using cluster-robust piecewise regression (16-weeks total). Linear mixed models examined the association between PA and mental health outcomes, while also examining the moderating influence of COVID phase. Significantly lower MVPA was observed from the end of pre-COVID to start of COVID by -18.2 min/day (p < 0.001) and significantly fewer steps/day was observed from end of pre-COVID to start of COVID by -3277 steps/day (p < 0.001). An MVPA \"catch-up\" effect was observed as there were small but positive week-over-week improvements during COVID for MVPA (b = 1.32 min/day, p < 0.001). The influence of COVID-19 phases had a notable impact on the relationships between PA/exercise and mental health outcomes. A discernible trend emerged, indicating stronger connections during the COVID period for anxiety and stress compared to the pre-COVID era. Interestingly, the moderating effect of COVID was opposite for mood and exercise. The COVID-19 pandemic led to a dramatic decline in PA among college students, coinciding with a period of heightened stress and anxiety. Despite a slight recovery in PA levels during the pandemic, the strengthened association between exercise and anxiety/stress during this time underscores the vital role of PA in promoting mental health. These findings highlight the importance of implementing behavior change strategies to maintain and promote student wellbeing.","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Søren Jessen, Júlia Prats Quesada, Andrea Di Credico, Roger Moreno-Justicia, Richard Wilson, Glenn Jacobson, Jens Bangsbo, Atul S Deshmukh, Morten Hostrup
Skeletal muscle mass plays a pivotal role in metabolic function, but conditions such as bed rest or injury often render resistance training impractical. The beta2-adrenergic receptor has been highlighted as a potential target to promote muscle hypertrophy and treat atrophic conditions. Here, we investigate the proteomic changes associated with beta2-adrenergic-mediated muscle hypertrophy, using resistance training as a hypertrophic comparator. We utilize MS-based proteomics to map skeletal muscle proteome remodeling in response to beta2-adrenergic stimulation or resistance training as well as cell model validation. We report that beta2-adrenergic stimulation mimics multiple features of resistance training in proteome-wide remodeling, comprising systematic upregulation of ribosomal subunits and concomitant downregulation of mitochondrial proteins. Approximately 20% of proteins were regulated in both conditions, comprising proteins involved in steroid metabolism (AKR1C1, AKR1C2, AKRC1C3), protein-folding (SERPINB1), and extracellular matrix organization (COL1A1, COL1A2). Among overall most significantly upregulated proteins were kelch-like family members (KLHL) 40 and 41. In follow-up experiments, we identify KLHL41 as having novel implications for beta2-adrenergic-mediated muscle hypertrophy. Treating C2C12 cells with beta2-agonist for 96 h increased myotube diameter by 48% (p < 0.001). This anabolic effect was abolished by prior knockdown of KLHL41. Using siRNA, KLHL41 abundance was decreased by 60%, and the anabolic response to beta2-agonist was diminished (+ 15%, i.e., greater in the presence of KLHL41, knock-down × treatment: p = 0.004). In conclusion, protein-wide remodeling induced by beta2-adrenergic stimulation mimics multiple features of resistance training, and thus the beta2-adrenergic receptor may be a target with therapeutic potential in the treatment of muscle wasting conditions without imposing mechanical load.
{"title":"Beta<sub>2</sub>-Adrenergic Stimulation Induces Resistance Training-Like Adaptations in Human Skeletal Muscle: Potential Role of KLHL41.","authors":"Søren Jessen, Júlia Prats Quesada, Andrea Di Credico, Roger Moreno-Justicia, Richard Wilson, Glenn Jacobson, Jens Bangsbo, Atul S Deshmukh, Morten Hostrup","doi":"10.1111/sms.14736","DOIUrl":"10.1111/sms.14736","url":null,"abstract":"<p><p>Skeletal muscle mass plays a pivotal role in metabolic function, but conditions such as bed rest or injury often render resistance training impractical. The beta<sub>2</sub>-adrenergic receptor has been highlighted as a potential target to promote muscle hypertrophy and treat atrophic conditions. Here, we investigate the proteomic changes associated with beta<sub>2</sub>-adrenergic-mediated muscle hypertrophy, using resistance training as a hypertrophic comparator. We utilize MS-based proteomics to map skeletal muscle proteome remodeling in response to beta<sub>2</sub>-adrenergic stimulation or resistance training as well as cell model validation. We report that beta<sub>2</sub>-adrenergic stimulation mimics multiple features of resistance training in proteome-wide remodeling, comprising systematic upregulation of ribosomal subunits and concomitant downregulation of mitochondrial proteins. Approximately 20% of proteins were regulated in both conditions, comprising proteins involved in steroid metabolism (AKR1C1, AKR1C2, AKRC1C3), protein-folding (SERPINB1), and extracellular matrix organization (COL1A1, COL1A2). Among overall most significantly upregulated proteins were kelch-like family members (KLHL) 40 and 41. In follow-up experiments, we identify KLHL41 as having novel implications for beta<sub>2</sub>-adrenergic-mediated muscle hypertrophy. Treating C2C12 cells with beta<sub>2</sub>-agonist for 96 h increased myotube diameter by 48% (p < 0.001). This anabolic effect was abolished by prior knockdown of KLHL41. Using siRNA, KLHL41 abundance was decreased by 60%, and the anabolic response to beta<sub>2</sub>-agonist was diminished (+ 15%, i.e., greater in the presence of KLHL41, knock-down × treatment: p = 0.004). In conclusion, protein-wide remodeling induced by beta<sub>2</sub>-adrenergic stimulation mimics multiple features of resistance training, and thus the beta<sub>2</sub>-adrenergic receptor may be a target with therapeutic potential in the treatment of muscle wasting conditions without imposing mechanical load.</p>","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142375897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Simon Walker, Meghan Tanel, Sakari Vekki, Dawson J. Kidgell, Stuart N. Baker
The StartReact test, increasingly popular for assessing cortico‐reticular functioning, is a valid method to influence the firing of reticulospinal tract neurons noninvasively. However, there remains limited evidence on how different stimuli employed in the StartReact test impact motor output in humans. The present study tested elbow flexor responses of 33 adults (aged 26–48 years) to visual stimuli only (LED light), audio‐visual (80 dB) stimuli, and startle‐inducing audio‐visual (120 dB) stimuli sitting with the arm supinated in an electromechanical dynamometer. Surface electromyogram (EMG) recorded muscle activity from the right biceps brachii muscle. Participants were presented with 20 stimuli for each of the three conditions in pseudorandom order with interstimulus intervals of ~8 s. Reaction times were calculated from the stimulus trigger to the initial rise in the EMG signal above 7 × SD from baseline. Rate of torque development (RTD) and EMG signals were recorded throughout and analyzed over their initial 50 ms and 100 ms time‐windows. Reaction times were reduced from visual (169 ± 23) to audio‐visual (140 ± 23) and further reduced to startle‐inducing audio‐visual stimuli (108 ± 19, p < 0.001). While RTD and EMG were consistently greatest following startle‐inducing stimuli (p < 0.001), they were also enhanced following all audio‐visual stimuli over 100 ms (p < 0.05). It appears that startle‐inducing audio‐visual stimuli result in shorter reaction times, increased RTD, and enhanced muscle activity within the initial 50 ms, likely from subcortical upregulation. However, the 100 ms time‐window suggests cortical upregulation following all audio‐visual stimuli considering the longer transmission times.
{"title":"The Effects of the StartReact on Reaction Time, Rate of Force Development, and Muscle Activity in Biceps Brachii","authors":"Simon Walker, Meghan Tanel, Sakari Vekki, Dawson J. Kidgell, Stuart N. Baker","doi":"10.1111/sms.14733","DOIUrl":"https://doi.org/10.1111/sms.14733","url":null,"abstract":"The StartReact test, increasingly popular for assessing cortico‐reticular functioning, is a valid method to influence the firing of reticulospinal tract neurons noninvasively. However, there remains limited evidence on how different stimuli employed in the StartReact test impact motor output in humans. The present study tested elbow flexor responses of 33 adults (aged 26–48 years) to visual stimuli only (LED light), audio‐visual (80 dB) stimuli, and startle‐inducing audio‐visual (120 dB) stimuli sitting with the arm supinated in an electromechanical dynamometer. Surface electromyogram (EMG) recorded muscle activity from the right biceps brachii muscle. Participants were presented with 20 stimuli for each of the three conditions in pseudorandom order with interstimulus intervals of ~8 s. Reaction times were calculated from the stimulus trigger to the initial rise in the EMG signal above 7 × SD from baseline. Rate of torque development (RTD) and EMG signals were recorded throughout and analyzed over their initial 50 ms and 100 ms time‐windows. Reaction times were reduced from visual (169 ± 23) to audio‐visual (140 ± 23) and further reduced to startle‐inducing audio‐visual stimuli (108 ± 19, <jats:italic>p</jats:italic> < 0.001). While RTD and EMG were consistently greatest following startle‐inducing stimuli (<jats:italic>p</jats:italic> < 0.001), they were also enhanced following all audio‐visual stimuli over 100 ms (<jats:italic>p</jats:italic> < 0.05). It appears that startle‐inducing audio‐visual stimuli result in shorter reaction times, increased RTD, and enhanced muscle activity within the initial 50 ms, likely from subcortical upregulation. However, the 100 ms time‐window suggests cortical upregulation following all audio‐visual stimuli considering the longer transmission times.","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stephanie L. Lazarczuk, Tyler J. Collings, Andrea H. Hams, Ryan G. Timmins, Anthony J. Shield, Rod S. Barrett, Matthew N. Bourne
Targeted resistance training stimulates hamstring muscle hypertrophy, but its effect on tendon‐aponeurosis geometry is unknown. This study examined changes in hamstring muscle, free tendon, and aponeurosis geometry following a 10 week Nordic or hip extension exercise intervention. Thirty recreationally active males were randomly allocated (n = 10 per group) to a Nordic, hip extension, or control group. Magnetic resonance imaging of both thighs was acquired pre‐ and post‐intervention. Changes in free tendon and aponeurosis volume for each hamstring muscle, biceps femoris long head (BFlh) aponeurosis interface area and muscle volume‐to‐interface area ratio were compared between groups. Regional changes in muscle CSA were examined via statistical parametric mapping. The change in semimembranosus free tendon volume was greater for the Nordic than control group (mean difference = 0.06 cm3, 95% CI = 0.02–0.11 cm3). No significant between‐group differences existed for other hamstring free tendons or aponeuroses. There were no between‐group differences in change in BFlh interface area. Change in BFlh muscle volume‐to‐interface area ratio was greater in the hip extension than Nordic (mean difference = 0.10, 95% CI = 0.007–0.19, p = 0.03) and control (mean difference = 0.12, 95% CI = 0.03–0.22, p = 0.009) groups. Change in muscle CSA following training was greatest in the mid‐portion of semitendinosus for both intervention groups, and the mid‐portion of BFlh for the hip extension group. There was limited evidence for tendon‐aponeurosis hypertrophy after 10 weeks of training with the Nordic or hip extension exercises. For the BFlh, neither intervention altered the interface area although hip extension training stimulated an increase in the muscle volume‐to‐interface area ratio, which may have implications for localized tissue strains. Alternative muscle‐tendon loading strategies appear necessary to stimulate hamstring tendon adaptations.
{"title":"Hamstring Muscle‐Tendon Geometric Adaptations to Resistance Training Using the Hip Extension and Nordic Hamstring Exercises","authors":"Stephanie L. Lazarczuk, Tyler J. Collings, Andrea H. Hams, Ryan G. Timmins, Anthony J. Shield, Rod S. Barrett, Matthew N. Bourne","doi":"10.1111/sms.14728","DOIUrl":"https://doi.org/10.1111/sms.14728","url":null,"abstract":"Targeted resistance training stimulates hamstring muscle hypertrophy, but its effect on tendon‐aponeurosis geometry is unknown. This study examined changes in hamstring muscle, free tendon, and aponeurosis geometry following a 10 week Nordic or hip extension exercise intervention. Thirty recreationally active males were randomly allocated (<jats:italic>n</jats:italic> = 10 per group) to a Nordic, hip extension, or control group. Magnetic resonance imaging of both thighs was acquired pre‐ and post‐intervention. Changes in free tendon and aponeurosis volume for each hamstring muscle, biceps femoris long head (BFlh) aponeurosis interface area and muscle volume‐to‐interface area ratio were compared between groups. Regional changes in muscle CSA were examined via statistical parametric mapping. The change in semimembranosus free tendon volume was greater for the Nordic than control group (mean difference = 0.06 cm<jats:sup>3</jats:sup>, 95% CI = 0.02–0.11 cm<jats:sup>3</jats:sup>). No significant between‐group differences existed for other hamstring free tendons or aponeuroses. There were no between‐group differences in change in BFlh interface area. Change in BFlh muscle volume‐to‐interface area ratio was greater in the hip extension than Nordic (mean difference = 0.10, 95% CI = 0.007–0.19, <jats:italic>p</jats:italic> = 0.03) and control (mean difference = 0.12, 95% CI = 0.03–0.22, <jats:italic>p</jats:italic> = 0.009) groups. Change in muscle CSA following training was greatest in the mid‐portion of semitendinosus for both intervention groups, and the mid‐portion of BFlh for the hip extension group. There was limited evidence for tendon‐aponeurosis hypertrophy after 10 weeks of training with the Nordic or hip extension exercises. For the BFlh, neither intervention altered the interface area although hip extension training stimulated an increase in the muscle volume‐to‐interface area ratio, which may have implications for localized tissue strains. Alternative muscle‐tendon loading strategies appear necessary to stimulate hamstring tendon adaptations.","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142275560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael A. Girdwood, Kay M. Crossley, Brooke E. Patterson, Ebonie K. Rio, Timothy S. Whitehead, Hayden G. Morris, Adam G. Culvenor
We aimed to report the trajectory of self‐reported outcomes up to 11 years post‐ACLR. We also explored the relationship between hop performance at 1 year and: (i) future self‐reported knee outcomes; and (ii) risk of subsequent knee events. 124 participants (43 women, mean age 31 ± 8 years) were recruited at 1 year following hamstring‐autograft ACLR. Hop performance was assessed with single‐forward and side‐hop tests. Follow‐up was completed at 3 (n = 114), 5 (n = 89) and 11 years (n = 72) post‐ACLR. Self‐reported outcomes were assessed at each follow‐up with the Knee injury Osteoarthritis Outcome Score (KOOS) pain and quality of life (QOL) subscales. Generalized linear mixed models estimated the relationship between hop performance and self‐reported outcomes. Subsequent knee events (new injury/surgery) to either knee were recorded, with the relationship between hop performance and risk of subsequent knee events analyzed with Cox proportional hazards. Self‐reported knee outcomes were stable (mean change < 10 points) across all timepoints but with major within‐sample variability. There was a modest relationship between greater hop performance at 1 year and better future KOOS‐pain (average marginal effect [AME] % improvement with + 1 cm single forward hop = 0.06% [95% CI 0.02–0.10]). A nonlinear spline relationship showed better single‐forward hop performance was associated with better KOOS‐QOL for scores < 108 cm, not present for higher hop scores > 108 cm. There were 21 index and 11 contralateral subsequent knee events. Hop performance was not related to risk of a subsequent knee event (hazard ratio index knee 0.99 [95% CI 0.98–1.02]). In conclusion, self‐reported knee pain and quality of life were generally stable across the 11‐year follow‐up period. Greater hop performance at 1‐year post‐ACLR was related to better self‐reported knee outcomes up to 11‐year follow‐up (of questionable clinical importance), but not associated with the risk of subsequent knee injury/surgery.
{"title":"People Are More Variable Than Their Hop Test Would Suggest: Hop Performance and Self‐Reported Outcomes Over 11 Years Following ACL Reconstruction","authors":"Michael A. Girdwood, Kay M. Crossley, Brooke E. Patterson, Ebonie K. Rio, Timothy S. Whitehead, Hayden G. Morris, Adam G. Culvenor","doi":"10.1111/sms.14727","DOIUrl":"https://doi.org/10.1111/sms.14727","url":null,"abstract":"We aimed to report the trajectory of self‐reported outcomes up to 11 years post‐ACLR. We also explored the relationship between hop performance at 1 year and: (i) future self‐reported knee outcomes; and (ii) risk of subsequent knee events. 124 participants (43 women, mean age 31 ± 8 years) were recruited at 1 year following hamstring‐autograft ACLR. Hop performance was assessed with single‐forward and side‐hop tests. Follow‐up was completed at 3 (<jats:italic>n</jats:italic> = 114), 5 (<jats:italic>n</jats:italic> = 89) and 11 years (<jats:italic>n</jats:italic> = 72) post‐ACLR. Self‐reported outcomes were assessed at each follow‐up with the Knee injury Osteoarthritis Outcome Score (KOOS) pain and quality of life (QOL) subscales. Generalized linear mixed models estimated the relationship between hop performance and self‐reported outcomes. Subsequent knee events (new injury/surgery) to either knee were recorded, with the relationship between hop performance and risk of subsequent knee events analyzed with Cox proportional hazards. Self‐reported knee outcomes were stable (mean change < 10 points) across all timepoints but with major within‐sample variability. There was a modest relationship between greater hop performance at 1 year and better future KOOS‐pain (average marginal effect [AME] % improvement with + 1 cm single forward hop = 0.06% [95% CI 0.02–0.10]). A nonlinear spline relationship showed better single‐forward hop performance was associated with better KOOS‐QOL for scores < 108 cm, not present for higher hop scores > 108 cm. There were 21 index and 11 contralateral subsequent knee events. Hop performance was not related to risk of a subsequent knee event (hazard ratio index knee 0.99 [95% CI 0.98–1.02]). In conclusion, self‐reported knee pain and quality of life were generally stable across the 11‐year follow‐up period. Greater hop performance at 1‐year post‐ACLR was related to better self‐reported knee outcomes up to 11‐year follow‐up (of questionable clinical importance), but not associated with the risk of subsequent knee injury/surgery.","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Patrick Vallance, Dawson J. Kidgell, Bill Vicenzino, Ashlyn K. Frazer, Alessandro Garofolini, Peter Malliaras
Patellar tendinopathy (PT) typically affects jumping‐sport athletes with functional impairments frequently observed. Alterations to the functional organization of corticomotor neurons within the motor cortex that project to working muscles are evident in some musculoskeletal conditions and linked to functional impairments. We aimed to determine if functional organization of corticomotor neuron projections differs between athletes with PT and asymptomatic controls, and if organization is associated with neuromuscular control. We used a cross‐sectional design, and the setting was Monash Biomedical Imaging. Basketball and volleyball athletes with (n = 8) and without PT (n = 8) completed knee extension and ankle dorsiflexion force matching tasks while undergoing fMRI. We determined functional organization via identification of the location of peak corticomotor neuron activation during respective tasks (expressed in X, Y, and Z coordinates) and calculated force matching accuracy for both tasks to quantify neuromuscular control. We observed significant interactions between group and coordinate plane for functional organization of corticomotor projections to knee extensors (p < 0.001) and ankle dorsiflexors (p = 0.016). Compared to controls, PT group peak corticomotor activation during the knee extension task was 9.6 mm medial (p < 0.001) and 5.2 mm posterior (p = 0.036), and during the ankle dorsiflexion task 8.2 mm inferior (p = 0.024). In the PT group, more posterior Y coordinate peak activation location during the knee extension task was associated with greater task accuracy (r = 0.749, p = 0.034). Functional organization of corticomotor neurons differed in jumping athletes with PT compared to controls. Links between functional organization and neuromuscular control in the PT group suggest organizational differences may be relevant to knee extension neuromuscular control preservation.
{"title":"The Functional Organization of Corticomotor Neurons Within the Motor Cortex Differs Among Basketball and Volleyball Athletes With Patellar Tendinopathy Compared to Asymptomatic Controls","authors":"Patrick Vallance, Dawson J. Kidgell, Bill Vicenzino, Ashlyn K. Frazer, Alessandro Garofolini, Peter Malliaras","doi":"10.1111/sms.14726","DOIUrl":"https://doi.org/10.1111/sms.14726","url":null,"abstract":"Patellar tendinopathy (PT) typically affects jumping‐sport athletes with functional impairments frequently observed. Alterations to the functional organization of corticomotor neurons within the motor cortex that project to working muscles are evident in some musculoskeletal conditions and linked to functional impairments. We aimed to determine if functional organization of corticomotor neuron projections differs between athletes with PT and asymptomatic controls, and if organization is associated with neuromuscular control. We used a cross‐sectional design, and the setting was Monash Biomedical Imaging. Basketball and volleyball athletes with (<jats:italic>n</jats:italic> = 8) and without PT (<jats:italic>n</jats:italic> = 8) completed knee extension and ankle dorsiflexion force matching tasks while undergoing fMRI. We determined functional organization via identification of the location of peak corticomotor neuron activation during respective tasks (expressed in X, Y, and Z coordinates) and calculated force matching accuracy for both tasks to quantify neuromuscular control. We observed significant interactions between group and coordinate plane for functional organization of corticomotor projections to knee extensors (<jats:italic>p</jats:italic> < 0.001) and ankle dorsiflexors (<jats:italic>p</jats:italic> = 0.016). Compared to controls, PT group peak corticomotor activation during the knee extension task was 9.6 mm medial (<jats:italic>p</jats:italic> < 0.001) and 5.2 mm posterior (<jats:italic>p</jats:italic> = 0.036), and during the ankle dorsiflexion task 8.2 mm inferior (<jats:italic>p</jats:italic> = 0.024). In the PT group, more posterior Y coordinate peak activation location during the knee extension task was associated with greater task accuracy (<jats:italic>r</jats:italic> = 0.749, <jats:italic>p</jats:italic> = 0.034). Functional organization of corticomotor neurons differed in jumping athletes with PT compared to controls. Links between functional organization and neuromuscular control in the PT group suggest organizational differences may be relevant to knee extension neuromuscular control preservation.","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Le Wei, Matthew N. Ahmadi, Raaj Kishore Biswas, Stewart G. Trost, Emmanuel Stamatakis
Step cadence‐based and machine‐learning (ML) methods have been used to classify physical activity (PA) intensity in health‐related research. This study examined the association of intensity‐specific PA duration with all‐cause (ACM) and CVD mortality using the cadence‐based and ML methods in 68 561 UK Biobank participants wearing wrist‐worn accelerometers. The two‐stage‐ML method categorized activity type and then intensity. The one‐level‐cadence‐method (1LC) derived intensity‐specific duration using all detected steps (including standing utilitarian steps) and cadence thresholds of ≥100 steps/min (moderate intensity) and ≥130 steps/min (vigorous intensity). The two‐level‐cadence‐method (2LC) detected ambulatory steps (i.e., walking and running) and then applied the same cadence thresholds. The 2LC exhibited the most pronounced association at the lower end of duration spectrum. For example, the 2LC showed the smallest minimum moderate‐to‐vigorous‐PA (MVPA) duration (amount associated with 50% of optimal risk reduction) with similar corresponding ACM hazard ratio (HR) to other methods (2LC: 2.8 min/day [95% CI: 2.6, 2.8], HR: 0.83 [95% CI: 0.78, 0.88]; 1LC, 11.1[10.8, 11.4], 0.80 [0.76, 0.85]; ML, 14.9 [14.6, 15.2], 0.82 [0.76, 0.87]). The ML elicited the greatest mortality risk reduction. For example, the medians and corresponding HR in VPA‐ACM association: 2LC, 2.0 min/day [95% CI: 2.0, 2.0], HR, 0.69 [95% CI: 0.61, 0.79]; 1LC, 6.9 [6.9, 7.0], 0.68 [0.60, 0.77]; ML, 3.2 [3.2, 3.2], 0.53 [0.44, 0.64]. After standardizing durations, the ML exhibited the most pronounced associations. For example, the standardized minimum durations in MPA‐CVD mortality association were: 2LC, −0.77; 1LC, −0.85; ML, −0.94; with corresponding HR of 0.82 [0.72, 0.92], 0.79 [0.69, 0.90], and 0.77 [0.69, 0.85], respectively. The 2LC exhibited the most pronounced association with all‐cause and CVD mortality at the lower end of the duration spectrum. The ML method provided the most pronounced association with all‐cause and CVD mortality, thus might be appropriate for estimating health benefits of moderate and vigorous intensity PA in observational studies.
{"title":"Comparing Cadence vs. Machine Learning Based Physical Activity Intensity Classifications: Variations in the Associations of Physical Activity With Mortality","authors":"Le Wei, Matthew N. Ahmadi, Raaj Kishore Biswas, Stewart G. Trost, Emmanuel Stamatakis","doi":"10.1111/sms.14719","DOIUrl":"https://doi.org/10.1111/sms.14719","url":null,"abstract":"Step cadence‐based and machine‐learning (ML) methods have been used to classify physical activity (PA) intensity in health‐related research. This study examined the association of intensity‐specific PA duration with all‐cause (ACM) and CVD mortality using the cadence‐based and ML methods in 68 561 UK Biobank participants wearing wrist‐worn accelerometers. The two‐stage‐ML method categorized activity type and then intensity. The one‐level‐cadence‐method (1LC) derived intensity‐specific duration using all detected steps (including standing utilitarian steps) and cadence thresholds of ≥100 steps/min (moderate intensity) and ≥130 steps/min (vigorous intensity). The two‐level‐cadence‐method (2LC) detected ambulatory steps (i.e., walking and running) and then applied the same cadence thresholds. The 2LC exhibited the most pronounced association at the lower end of duration spectrum. For example, the 2LC showed the smallest minimum moderate‐to‐vigorous‐PA (MVPA) duration (amount associated with 50% of optimal risk reduction) with similar corresponding ACM hazard ratio (HR) to other methods (2LC: 2.8 min/day [95% CI: 2.6, 2.8], HR: 0.83 [95% CI: 0.78, 0.88]; 1LC, 11.1[10.8, 11.4], 0.80 [0.76, 0.85]; ML, 14.9 [14.6, 15.2], 0.82 [0.76, 0.87]). The ML elicited the greatest mortality risk reduction. For example, the medians and corresponding HR in VPA‐ACM association: 2LC, 2.0 min/day [95% CI: 2.0, 2.0], HR, 0.69 [95% CI: 0.61, 0.79]; 1LC, 6.9 [6.9, 7.0], 0.68 [0.60, 0.77]; ML, 3.2 [3.2, 3.2], 0.53 [0.44, 0.64]. After standardizing durations, the ML exhibited the most pronounced associations. For example, the standardized minimum durations in MPA‐CVD mortality association were: 2LC, −0.77; 1LC, −0.85; ML, −0.94; with corresponding HR of 0.82 [0.72, 0.92], 0.79 [0.69, 0.90], and 0.77 [0.69, 0.85], respectively. The 2LC exhibited the most pronounced association with all‐cause and CVD mortality at the lower end of the duration spectrum. The ML method provided the most pronounced association with all‐cause and CVD mortality, thus might be appropriate for estimating health benefits of moderate and vigorous intensity PA in observational studies.","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142166241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to \"Lateral Knee Snapping in an Elite Judo Athlete: 'Sono-Acrobatics' of the Popliteus Tendon\".","authors":"","doi":"10.1111/sms.14724","DOIUrl":"https://doi.org/10.1111/sms.14724","url":null,"abstract":"","PeriodicalId":21466,"journal":{"name":"Scandinavian Journal of Medicine & Science in Sports","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142154879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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