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.

ChatGPT and exercise prescription:Human vs.machine or human plus machine?

The power of artificial intelligence(AI)to create stories,music,art,and other creative projects has been demonstrated and criticized over recent decades in media,mainly because of the idea that AI will replace human jobs.Most recently,in November 2022,reactions to Chat Generative Pre-training Transformer(ChatGPT)release for public use reverberated in news and social media headlines,while its users exceeded100 million in just a few weeks.ChatGPT is a natural language processing program created by AI non-profit OpenAI Inc.

Effect of resistance training volume on body adiposity,metabolic risk,and inflammation in postmenopausal and older females:Systematic review and meta-analysis of randomized controlled trials

Purpose:This meta-analytical study aimed to explore the effects of resistance training(RT) volume on body adiposity,metabolic risk,and inflammation in postmenopausal and older females.Methods:A systematic search was performed for randomized controlled trials in PubMed,Scopus,Web of Science,and SciELO.Randomized controlled trials with postmenopausal and older females that compared RT effects on body adiposity,metabolic risk,and inflammation with a control group(CG) were included.Independent reviewers selected the studies,extracted the data,and performed the risk of bias and certainty of the evidence(Grading of Recommendations,Assessment,Development,and Evaluation(GRADE)) evaluations.Total body and abdominal adiposity,blood lipids,glucose,and C-reactive protein were included for meta-analysis.A random-effects model,standardized mean difference(Hedges’ g),and 95% confidence interval(95%CI) were used for meta-analysis.Results:Twenty randomized controlled trials(overall risk of bias:some concerns;GRADE:low to very low) with overweight/obese postmenopausal and older females were included.RT groups were divided into low-volume RT(LVRT,~44 sets/week) and high-volume RT(HVRT,~77 sets/week).Both RT groups presented improved body adiposity,metabolic risk,and inflammation when compared to CG.However,HVRT demonstrated higher effect sizes than LVRT for glucose(HVRT=-1.19;95%CI:-1.63 to-0.74;LVRT=-0.78;95%CI:-1.15 to-0.41) and C-reactive protein(HVRT=-1.00;95%CI:-1.32 to-0.67;LVRT=-0.34;95%CI,-0.63 to-0.04)) when compared to CG.Conclusion:Compared to CG,HVRT protocols elicit greater improvements in metabolic risk and inflammation outcomes than LVRT in overweight/obese postmenopausal and older females.

Liver Histology after Chronic Use of Alcohol and Exercise Training in Rats

Objectives： To investigate the effects of physical training on the liver morphology and morphometry after chronic use of alcohol in rats. Methods： Twenty-four Wistar rats were housed in cages with controlled environment and randomly divided into four groups according to treatment received. In the initial treatment, alcohol was administered to SA （sedentary alcohol） and EA （exercise alcohol） groups. After four weeks, physical training program was held on a treadmill with EA and EC （exercise control） groups. Area, perimeter, maximum and minimum diameter and form factor of nucleus and cytoplasm of hepatocytes were analyzed. Key findings： Micro-vesicular fatty degeneration, predominantly pericentrolobular, of mild to moderate intensity, was found especially in animals treated with alcohol. EC group showed nucleus area greater than the nucleus area of EA and SA groups. The form factor was lower in the EC group than in the EA group. EA group showed maximum cytoplasm diameter is smaller than in SC （sedentary control） group. Conclusions： Physical training for two weeks was not enough to suppress histopathologic changes in the liver caused by chronic use of alcohol in rats. Chronic use of alcohol seems to have minimized the beneficial effect of physical training in the nucleus area of hepatocytes.

T10 Test as an Alternative Method to Assess Critical Speed and its Potential Application to Runners

Exercise intensity is usually prescribed based on a metabolic marker,such as maximum oxygen uptake or maximal lactate steady state.Those markers,however,face some difficulties regarding their practical applicability to the general popula-tion.The critical speed emerges as an alternative parameter to determine aerobic exercise intensities through maximal tests using ergometers or field tests,demanding few resources.We evaluated the fidelity of test to predict critical speed and if this parameter could be used to prescribe intensity in aerobic exercise.One hundred recreational runners performed the T10 test and a conventional critical speed test to define running speeds.Out of them,44 runners proceed continuous and interval races.The critical speed assessed from T10 test was then compared to critical speed measured by three maximal runs in the track field(1200 m,2400 m,and 3600 m).We found a strong correlation(r=0.91)and did not find statistical differences(t=1.8,P=0.90)between critical speed assessed by T10(3.89±0.49 m/s)and field-test(3.85±0.51 m/s).T10 is also better associated with running and interval running speeds than metabolic markers.T10 test can be used as a valid alternative method to assess critical speed and to prescribe runs.