2024 Wheelchair Compendium of Physical Activities:An update of activity codes and energy expenditure values

Purpose:This paper presents an update of the 2011 Wheelchair Compendium of Physical Activities designed for wheelchair users and is referred to as the 2024 Wheelchair Compendium.The Wheelchair Compendium aims to curate existing knowledge of the energy expenditure for wheelchair physical activities(PAs).Methods:A systematic review of the published energy expenditure of PA for wheelchair users was completed between 2011 and May 2023.We added these data to the 2011 Wheelchair Compendium data that was compiled previously in a systematic review through 2011.Results:A total of 47 studies were included,and 124 different wheelchair PA reported energy expenditure values ranging from 0.8 metabolic equivalents for wheelchair users(filing papers,light effort)to 11.8 metabolic equivalents for wheelchair users(Nordic sit skiing).Conclusion:In introducing the updated 2024 Wheelchair Compendium,we hope to bridge the resource gap and challenge the prevailing narratives that inadvertently exclude wheelchair users from physical fitness and health PAs.

Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older adults.MET values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older adults.Results:We identified 68 articles and extracted energy expenditure data on 427 PAs.From these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older adults.We developed a website to present the OA Compendium MET_(60+)values:https://pacompendium.com.Conclusion:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older adults.It is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice.

The influence of resistance exercise training prescription variables on skeletal muscle mass,strength,and physical function in healthy adults:An umbrella review

Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines,we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass(or its proxies),strength,and/or physical function in healthy adults aged>18 years.Results:We identified 44 systematic reviews that met our inclusion criteria.The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews;standardized effectiveness statements were generated.We found that RT was consistently a potent stimulus for increasing skeletal muscle mass(4/4 reviews provide some or sufficient evidence),strength(4/6 reviews provided some or sufficient evidence),and physical function(1/1 review provided some evidence).RT load(6/8 reviews provided some or sufficient evidence),weekly frequency(2/4 reviews provided some or sufficient evidence),volume(3/7 reviews provided some or sufficient evidence),and exercise order(1/1 review provided some evidence)impacted RT-induced increases in muscular strength.We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass,while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass.There was insufficient evidence to conclude that time of day,periodization,inter-set rest,set configuration,set end point,contraction velocity/time under tension,or exercise order(only pertaining to hypertrophy)influenced skeletal muscle adaptations.A paucity of data limited insights into the impact of RT prescription variables on physical function.Conclusion:Overall,RT increased muscle mass,strength,and physical function compared to no exercise.RT intensity(load)and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy.RT volume(number of sets)influenced muscular strength and hypertrophy.

There is more to the knee joint than just the quadriceps:A systematic review with meta-analysis and evidence gap map of hamstring strength,flexibility,and morphology in individuals with gradual-onset knee disorders

Background:Impairments in hamstring strength,flexibility,and morphology have been associated with altered knee biomechanics,pain,and function.Determining the presence of these impairments in individuals with gradual-onset knee disorders is important and may indicate targets for assessment and rehabilitation.This systematic review aimed to synthesize the literature to determine the presence of impairments in hamstring strength,flexibility,and morphology in individuals with gradual-onset knee disorders.Methods:Five databases(MEDLINE,Embase,CINAHL,SPORTDiscus,and Web of Science)were searched from inception to September 2022.Only studies comparing hamstring outcomes(e.g.,strength,flexibility,and/or morphology)between individuals with gradual-onset knee disorders and their unaffected limbs or pain-free controls were included.Meta-analyses for each knee disorder were performed.Outcome-level certainty was assessed using the Grading of Recommendations Assessment,Development,and Evaluation,and evidence gap maps were created.Results:Seventy-nine studies across 4 different gradual-onset knee disorders(i.e.,knee osteoarthritis(OA),patellofemoral pain(PFP),chondromalacia patellae,and patellar tendinopathy)were included.Individuals with knee OA presented with reduced hamstring strength compared to pain-free controls during isometric(standard mean difference(SMD)=-0.76,95%confidence interval(95%CI):-1.32 to-0.21)and concentric contractions(SMD=-0.97,95%CI:-1.49 to-0.45).Individuals with PFP presented with reduced hamstring strength compared to painfree controls during isometric(SMD=-0.48,95%CI:-0.82 to-0.14),concentric(SMD=-1.07,95%CI:-2.08 to-0.06),and eccentric contractions(SMD=-0.59,95%CI:-0.97 to-0.21).No differences were observed in individuals with patellar tendinopathy.Individuals with PFP presented with reduced hamstring flexibility when compared to pain-free controls(SMD=-0.76,95%CI:-1.15 to-0.36).Evidence gap maps identified insufficient evidence for chondromalacia patellae and hamstring morphology across all gradual-onset knee disorders.Conclusion:Our findings suggest that assessing and targeting impairments in hamstring strength and flexibility during rehabilitation may be recommended for individuals with knee OA or PFP.

The effectiveness of physical activity interventions on blood pressure in children and adolescents:A systematic review and network meta-analysis

Background:High blood pressure(BP)is a major contributor to mortality and cardiovascular diseases.Despite the known benefits of exercise for reducing BP,it is crucial to identify the most effective physical activity(PA)intervention.This systematic review and network meta-analysis(NMA)aimed to evaluate the available evidence on the effectiveness of various PA interventions for reducing BP and to determine their hierarchy based on their impact on BP.Methods:A search of PubMed,SPORTDiscus,PsycINFO,Web of Science,CINAHL,Cochrane,and Eric databases was conducted up to December 2022 for this systematic review and NMA.Randomized controlled trials and quasi-experimental studies targeting healthy children and adolescents aged 6-12 years old were included in this study.Only studies that compared controlled and intervention groups using PA or exercise as the major influence were included.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines.Three independent investigators performed the literature screening,data extraction,and risk of bias assessment.We used Bayesian arm-based NMA to synthesize the data.The primary outcomes were systolic BP and diastolic BP.We calculated the mean differences(MDs)in systolic BP and diastolic BP before and after treatment.Mean treatment differences were estimated using NMA and random-effect models.Results:We synthesized 27 studies involving 15,220 children and adolescents.PA combined with nutrition and behavior change was the most effective intervention for reducing both systolic BP and diastolic BP(MD=-8.64,95%credible interval(95%CI):-11.44 to-5.84;MD=-6.75,95%CI:-10.44 to-3.11),followed by interventions with multiple components(MD=-1.39,95%CI:-1.94 to-0.84;MD=-2.54,95%CI:-4.89 to-0.29).Conclusion:Our findings suggest that PA interventions incorporating nutrition and behavior change,followed by interventions with multiple components,are most effective for reducing both systolic BP and diastolic BP in children and adolescents.

Physical activity with or without dietary intervention for the prevention of cardiovascular diseases

We and others have published extensively on the benefits of physical activity(PA),exercise training,and cardiorespiratory fitness(CRF)to decrease the prevalence of cardiovascular diseases(CVDs)and CVD and all-cause morbidity and mortality.^(1-5)Both PA and CRF are important;however,CRF,which is mostly obtained through PA,although there is a genetic component,seems to be even more important than PA for predicting prognosis.^(1,4-6)Certainly,the wealth of data from across the world has indicated that increasing PA to enhance CRF while mitigating sedentary behavior would go a long way to lessen the world-wide obesity epidemic and reduce CVD and all-cause mortality.

Promoting public health through the 2024 Compendium of Physical Activities:Strategies for adults,older adults,and wheelchair users

Physical activity(PA)is fundamentally linked to public health,^(1)providing benefits including chronic disease prevention and treatment,^(2)mental health,^(3)musculoskeletal health,^(4)and healthy aging,^(5)along with socioeconomic advantages.^(6)These benefits highlight the importance of promoting PA for all populations.The recent publication of the Compendium of Physical Activities(Compendium)serves as a valuable resource,^(7)offering an updated and expanded guide for adults(ages 19-59)with tailored energy cost values for diverse populations.

Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week:An analysis with 707,616 adolescents

Background:Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity(MVPA).However,using only this cut-off could hide important information.For instance,from a population-level point of view,increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate levels.Also,including a more sensitive cut-point of≥1 days per week could be an additional strategy for identifying those with low access/opportunities for physical activity practice.Thus,the current study aims to estimate the prevalence of≥60 min of MVPA≥1 days per week among adolescents globally,and to describe any relevant gender inequalities.Methods:We used representative datasets from 146 countries/territories collected between 2003 and 2019.MVPA was self-reported.Participants were grouped into younger(≤14 years old)and older(>14 years old)adolescents.Crude Poisson regression models were used to identify the relative differences in≥60 min of MVPA≥1 days per week between boys and girls,and random-effects meta-analysis models were used to identify the pooled estimates.Analyses were stratified by country and region.Results:Approximately 80%of both younger and older adolescents reported≥60 min of MVPA≥1 days per week.This prevalence was≥94%in Europe and Central Asia and North America,while the estimates for the other regions were<77%.The prevalence of≥60 min of MVPA≥1 days per week was higher among boys than girls,with the largest differences occurring among the oldest adolescents(Prevalence ratio_(≤14y)=1.04(95%confidence interval(95%CI)):1.03-1.04)vs.Prevalence ratio_(>14y)=1.09(95%CI:1.08-1.10)).Conclusion:Approximately 8 out of 10 adolescents reported accumulating≥60 min of MVPA≥1 days per week,with notable differences between regions.Gender differences were observed in several countries,especially among the oldest adolescents.Priorities for physical activity promotion among adolescents should include increasing access/opportunities for physical activity among those who do not achieve≥60 min of MVPA≥1 days per week and reducing gender inequalities.

The protective effect of carnosic acid on dextran sulfate sodium-induced colitis based on metabolomics and gut microbiota analysis

Accumulating evidence suggests that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease(IBD).Carnosic acid(CA)is a major antioxidant component of rosemary and sage.Herein,we investigated the protective effects of dietary CA on dextran sodium sulfate(DSS)-induced colitis mouse model with an emphasis on its impact on the composition and metabolic function of gut microbiota.We found that CA effectively attenuated DSS-stimulated colitis in mice,as evidenced by reduced disease activity index(DAI),and systemic and colonic inflammation.Additionally,CA restored microbial diversity and improved the composition of gut microbiota in DSS-treated mice.Moreover,Spearman’s correlation coefficient showed a significant correlation between the fecal metabolites and the gut microbiota species.Changes in gut microbiota and the correlated metabolites might partially explain CA’s anti-inflammatory effects against colitis.Future clinical trials are needed to determine the therapeutic effects and mechanisms of CA on IBD in humans.

The expectancy-value theory:A meta-analysis of its application in physical education

Background:The purpose of motivating students is to enhance their learning achievement.The expectancy-value theory(EVT)has demonstrated its efficacy in motivating students in classrooms and in gymnasia.Understanding student motivation in physical education is needed.This metaanalysis review aimed to reveal the determinants and functions of EVT by evaluating the evidence in physical education research.Methods:We followed the Preferred Reporting Items for Systematic Review and Meta-Analyses(PRISMA)guidelines to identify and meta-analyze the current research literature published from January 2010 to December 2020 by generating and analyzing the effect sizes from the studies.Results:A total of 31 studies were included.The results show that social support,motivation of teachers and peers,and positive class climate can predict student EVT motivation.EVT motivation predicts student learning behaviors,situational interests,fitness performance,health behavior function,out-of-school physical activity,and physical skill development.Conclusion:EVT motivation could facilitate learning behaviors and situational interest development in the gymnasium.It might lead to fitness enhancement,health behavior change,out-of-school physical activity participation,and physical skill development.Fostering a learning environment with a mastery-centered and/or student autonomy approach where students perceived success and the task values can enhance and maximize student EVT motivation and learning achievement.

Exercise and oncology:The role of physical activity in disease prevention and health promotion

The field of exercise-oncology has evolved significantly over the past 30 years.Numerous studies have examined the role of structured exercise interventions—often incorporating aerobic or resistance training at moderate-to-vigorous intensities,sometimes in conjunction with multi-modal strategies—for individuals living with and beyond cancer.

Effects of personalized exercise prescriptions and social media delivered through mobile health on cancer survivors’physical activity and quality of life

Purpose This study aimed to examine the effects of a multi-component mobile health intervention(wearable,apps,and social media)on cancer survivors’(CS')physical activity(PA),quality of life,and PA determinants compared to exercise prescription only,social media only,and attention control conditions.Methods A total of 126 CS(age=60.37±7.41 years,mean±SD)were recruited from the United States.The study duration was 6 months and participants were randomly placed into 4 groups.All participants received a Fitbit tracker and were instructed to install its companion app to monitor their daily PA.They(1)received previously established weekly personalized exercise prescriptions via email,(2)received weekly Facebook health education and interacted with one another,(3)received both Conditions 1 and 2,or(4)were part of the control condition,meaning they adopted usual care.CS PA daily steps,quality of life(i.e.,physical health and mental health),and PA determinants(e.g.,self-efficacy,social support)were measured at baseline,3 months,and 6 months.Results The final sample size included 123 CS.The results revealed only the multi-component condition had greater improvements in PA daily steps than the control condition post-intervention(95%confidence interval(95%CI):368–2951;p<0.05).Similarly,those in the multi-component condition had significantly greater increased physical health than the control condition(95%CI:–0.41 to–0.01;p<0.05)over time.In addition,the social media condition had significantly greater increased perceived social support than the control condition(95%CI:0.01–0.93;p<0.05).No other significant differences on outcomes were identified.Conclusion The study findings suggest that the implementation of a multi-component mobile health intervention had positive effects on CS PA steps and physical health.Also,offering social media intervention has the potential to improve CS perceived social support.

Validation of the Chinese Version of the Affective Exercise Experiences Questionnaire (AFFEXX-C)

Despite the well-established benefits of regular physical activity(PA)on health,a large proportion of the world population does not achieve the recommended level of regular PA.Although affective experiences toward PA may play a key role to foster a sustained engagement in PA,they have been largely overlooked and crudely measured in the existing studies.To address this shortcoming,the Affective Exercise Experiences(AFFEXX)questionnaire has been developed to measure such experiences.Specifically,this questionnaire was developped to assess the following three domains:antecedent appraisals(e.g.,liking vs.disliking exercise in groups),core affective exercise experiences(i.e.,pleasure vs.displeasure,energy vs.tiredness,and calmness vs.tension),and exercise motivation(i.e.,attraction vs.antipathy toward exercise).The current study aimed to validate a Chinese version of the AFFEXX questionnaire(AFFEXX-C).In study 1,722 Chinese college students provided data for analyses of factorial,convergent,discriminant,criterion validity,and test-retest reliability of the AFFEXX-C.In addition,1,300 college students were recruited in study 2 to further validate its structural model.Results showed that the AFFEXX-C demonstrates a goodfit and reliability.Additionally,results further supported the hypothesized model based on previous research:antecedent appraisals predicted core affective exercise experiences,which in turn predicted attraction-antipathy toward physical exercise.The AFFEXX-C was found to be a reliable and valid measure of affective exercise experiences in a population of Chinese college students.

The impact of height-adjustable desks and classroom prompts on classroom sitting time,social,and motivational factors among adolescents

Purpose:This quasi-experimental study examined the impact of height-adjustable desks in combination with prompts to break up prolonged sitting time during class time and identified social and motivational factors associated with breaking up sitting time among adolescents.Teachers’perceptions of strategies were also examined.Methods:Over 17 weeks,1 classroom in a government secondary school in Melbourne,Australia,was equipped with 27 height-adjustable desks and prompts(posters and desk stickers)to break up classroom sitting time.Teachers received professional development in the use of the desks and prompts.One group of adolescents(n=55)had 2-5 lessons/week using the height-adjustable desks in an intervention classroom,and a comparison group matched by year level and subject(n=50)was taught in traditional“seated”classrooms.Adolescents wore an activPAL monitor at baseline(T0),4 weeks(T1),and 17 weeks(T2)and completed a survey at T0 and T2.Six teachers participated in interviews at T2.Effect sizes were calculated(d).Results:Linear mixed models found that,compared to the traditional“seated”classrooms,the adolescents in the intervention classroom had significantly lower sitting time(T1:-9.7 min/lesson,d=-0.96;T2:-6.7 min/lesson,d=-0.70)and time spent in sitting bouts>15 min(T2:-11.2 min/lesson,d=-0.62),and had significantly higher standing time(T1:7.3 min/lesson,d=0.84;T2:5.8 min/lesson,d=0.91),number of breaks from sitting(T1:1.3 breaks/lesson,d=0.49;T2:1.8 breaks/lesson,d=0.67),and stepping time(T1:2.5 min/lesson,d=0.66).Intervention classroom adolescents reported greater habit strength(d=0.58),self-efficacy for breaking up sitting time(d=0.75),and indicated that having a teacher/classmate remind them to stand as helpful(d=0.50).Conclusion:This intervention shows promise for targeting sitting behaviors in the classroom and indicates that incorporating social and motivational strategies may further enhance outcomes.

Effects of contact/collision sport history on gait in early-to mid-adulthood

Background:To determine the effect of contact/collision sport participation on measures of single-task(ST)and dual-task(DT)gait among early-to middle-aged adults.Methods:The study recruited 113 adults(34.88±11.80 years,(mean±SD);53.0%female)representing 4 groups.Groups included(a)former non-contact/collision athletes and non-athletes who are not physically active(n=28);(b)former non-contact/collision athletes who are physically active(n=29);(c)former contact/collision sport athletes who participated in high-risk sports and are physically active(n=29);and(d)former rugby players with prolonged repetitive head impact exposure history who are physically active(n=27).Gait parameters were collected using inertial measurement units during ST and DT gait.DT cost was calculated for all gait parameters(double support,gait speed,and stride length).Groups were compared first using one-way analysis of covariance.Then a multiple regression was performed for participants in the highrisk sport athletes and repetitive head impact exposure athletes groups only to predict gait outcomes from contact/collision sport career duration.Results:There were no significant differences between groups on any ST,DT,or DT cost outcomes(p>0.05).Contact/collision sport duration did not predict any ST,DT,or DT cost gait outcomes.Conclusion:Years and history of contact/collision sport participation does not appear to negatively affect or predict neurobehavioral function in early-to mid-adulthood among physically active individuals.

The resistive range of motion exercise training in Duchenne muscular dystrophy:a case study

Background:To determine the effectiveness of resistive range of motion exercises in improving muscle strength and functional abilities in Duchenne muscular dystrophy.The study was also aimed to determine if resistive range of motion exercises can slow down the progression of the disease.Methods:A seven-year-old male child was diagnosed with Duchenne muscle dystrophy presented to outpatient physiotherapy clinic.The patient was presented with difficulty in stair climbing,sitting up from the floor,fatigue,and muscle weakness specifically weakness in the proximal limb muscles.The progressive resistive range of motion training was implemented for four years to improve muscle strength and functional abilities.The medical research council grading scale,north ambulatory assessment scale,and creatine kinase were used to evaluate muscle strength,functional abilities,and creatine kinase levels.Results:The muscular strength and functional abilities did not improve after four years of exercise training.The creatine kinase levels were decreased over the period of four years.Conclusion:Resistive range of motion exercises are helpful in maintaining the muscular strength and functional abilities in Duchenne muscular dystrophy.

Effectiveness of progressive resistance training in improving muscle strength in myasthenia gravis:a single subject study design

Background:To investigate the effectiveness of the progressive resistance training(PRT)using thera band in improving muscle strength in myasthenia gravis(MG).Methods:In this prospective study,12 MG patients with generalised stable disease performed progressive resistance training with thera band for four times per week for 24 weeks.The isometric muscle force of shoulder abductors,biceps brachii and knee extensors using handheld dynamometer,Myasthenia Gravis Composite(MGC)score,Quantitative myasthenia gravis score(QMG),were assessed before and after the training period.Results:Progressive resistance training was well tolerated,and the isometric muscle strength was significantly improved in shoulder abductors,biceps brachii and knee extensors(P<0.05).The disease course(QMG and MGC)was slowed down and improved(P<0.05).Conclusion:Progressive resistance training is effective in improving muscle strength specifically in most affected muscles in MG.

Speed and surface steepness affect internal tibial loading during running

Background:Internal tibial loading is influenced by modifiable factors with implications for the risk of stress injury.Runners encounter varied surface steepness(gradients)when running outdoors and may adapt their speed according to the gradient.This study aimed to quantify tibial bending moments and stress at the anterior and posterior peripheries when running at different speeds on surfaces of different gradients.Methods:Twenty recreational runners ran on a treadmill at 3 different speeds(2.5 m/s,3.0 m/s,and 3.5 m/s)and gradients(level:0%;uphill:+5%,+10%,and+15%;downhill:-5%,-10%,and-15%).Force and marker data were collected synchronously throughout.Bending moments were estimated at the distal third centroid of the tibia about the medial-lateral axis by ensuring static equilibrium at each 1%of stance.Stress was derived from bending moments at the anterior and posterior peripheries by modeling the tibia as a hollow ellipse.Two-way repeated-measures analysis of variance were conducted using both functional and discrete statistical analyses.Results:There were significant main effects for running speed and gradient on peak bending moments and peak anterior and posterior stress.Higher running speeds resulted in greater tibial loading.Running uphill at+10%and+15%resulted in greater tibial loading than level running.Running downhill at-10%and-15%resulted in reduced tibial loading compared to level running.There was no difference between+5%or-5%and level running.Conclusion:Running at faster speeds and uphill on gradients≥+10%increased internal tibial loading,whereas slower running and downhill running on gradients≥-10%reduced internal loading.Adapting running speed according to the gradient could be a protective mechanism,providing runners with a strategy to minimize the risk of tibial stress injuries.

Differences between lower extremity joint running kinetics captured by marker-based and markerless systems were speed dependent

Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as running.Applied studies using markerless systems in clinical and sports settings are still lacking.Thus,the present study compared running biomechanics estimated by marker-based and markerless systems.Given running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating study.Methods:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic methods.Time series analysis and statistical parametric mapping were used to determine system differences.Results:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most cases.Conclusion:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused attention.Based on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless vs.marker-based systems.The differences were amplified by running speed.

Reactive oxygen species promote endurance exercise-induced adaptations in skeletal muscles

The discovery that contracting skeletal muscle generates reactive oxygen species(ROS)was first reported over 40 years ago.The prevailing view in the 1980s was that exercise-induced ROS production promotes oxidation of proteins and lipids resulting in muscle damage.However,a paradigm shift occurred in the 1990s as growing research revealed that ROS are signaling molecules,capable of activating transcriptional activators/coactivators and promoting exercise-induced muscle adaptation.Growing evidence supports the notion that reduction-oxidation(redox)signaling pathways play an important role in the muscle remodeling that occurs in response to endurance exercise training.This review examines the specific role that redox signaling plays in this endurance exercise-induced skeletal muscle adaptation.We begin with a discussion of the primary sites of ROS production in contracting muscle fibers followed by a summary of the antioxidant enzymes involved in the regulation of ROS levels in the cell.We then discuss which redox-sensitive signaling pathways promote endurance exercise-induced muscle adaptation and debate the strength of the evidence supporting the notion that redox signaling plays an essential role in muscle adaptation to endurance exercise training.In hopes of stimulating future research,we highlight several important unanswered questions in this field.