BRICS is the acronym for an international association of 5 major emerging national economies: Brazil, Russia, India, China, and South Africa.According to the World Economic Forum, the BRICS economies are the most com...BRICS is the acronym for an international association of 5 major emerging national economies: Brazil, Russia, India, China, and South Africa.According to the World Economic Forum, the BRICS economies are the most competitive among all cotmtries and are distinguished by their significant regional and global influence. The health and wellness of the people within these countries is a primary agenda item of these governments for connecting their fast economic growth and the need to provide a better quality of life. As of 2015, BRICS countries represent 〉3.6 billion people or one-half of the world population. All 5 countries are members of the top 25 countries of the world by population and 4 of these cotmtries make the top 10 on this list.展开更多
Objectives:Aerobic exercise training can increase skeletal muscle mitochondrial content.Supine exercise training with legs above the heart potentially augments these increases.However,the impact of supine exercise tra...Objectives:Aerobic exercise training can increase skeletal muscle mitochondrial content.Supine exercise training with legs above the heart potentially augments these increases.However,the impact of supine exercise training on mitochondrial biogenesis and cardiovascular adaptations remains unclear.Methods:In this single-centred,randomized,parallel arm trial,19 recreationally active individuals underwent seven sessions of either supine with legs up(SUP;n=9,6 females)or upright with legs down(UP;n=10,7 females)aerobic training on a recumbent bike at 71±7%and 71±2%of peak work rate(WRpeak),respectively.The study aimed to test the effects of training with decreased muscle oxygenation on indices of muscle mitochondrial remodelling.Secondary outcomes included exercise performance,muscle oxygenation,and cardiovascular responses.Results:Secondary outcomes revealed significant interaction effects for time to fatigue(TTF)and WRpeak in the SUP group during supine testing,suggesting enhanced exercise tolerance and performance.No between group interaction effects were observed for upright testing.No clear effects on mitochondrial biogenesis were observed based on expression of mitochondrial protein subunits and transcriptional regulators.Acutely,HRpeak was lower during the SUP Test compared to the UP Test.No central cardiovascular adaptations were observed following training.Conclusions:Our exploratory analyses showed that supine aerobic training more effectively improves supine exercise tolerance and performance compared with upright training,despite no differences in measured proteins related to mitochondrial biogenesis.Further research is needed to elucidate the mechanisms underlying these postural-specific training effects.Registration:clinicaltrials.gov:NCT04151095.展开更多
Background:Stretching has wide appeal,but there seems to exist some mismatch between its purported applications and what the evidence shows.There is compelling evidence for some stretching applications,but for others,...Background:Stretching has wide appeal,but there seems to exist some mismatch between its purported applications and what the evidence shows.There is compelling evidence for some stretching applications,but for others,the evidence seems heterogeneous or unsupportive.The discrepancies even affect some systematic reviews,possibly due to heterogeneous eligibility criteria and search strategies.This consensus paper seeks to unify the divergent findings on stretching and its implications for both athletic performance and clinical practices by delivering evidence-based recommendations.Methods:A panel of 20 experts with a blend of practical experience and scholarly knowledge was assembled.The panel meticulously reviewed existing systematic reviews,defined key terminologies(e.g.,consensus definitions for different stretching modes),and crafted guidelines using a Delphi consensus approach(minimum required agreement:80%).The analysis focused on 8 topics,including stretching's acute and chronic(long-term)effects on range of motion,strength performance,muscle hypertrophy,stiffness,injury prevention,muscle recovery,posture correction,and cardiovascular health.Results:There was consensus that chronic and acute stretching(a)improves range of motion(although alternatives exist)and(b)reduces muscle stiffness(which may not always be desirable);the panel also agreed that chronic stretching(c)may promote vascular health,but more research is warranted.In contrast,consensus was found that stretch training does not(a)contribute substantively to muscle growth,(b)serve as an allencompassing injury prevention strategy,(c)improve posture,or(d)acutely enhance post-exercise recovery.Conclusion:These recommendations provide guidance for athletes and practitioners,highlighting research gaps that should be addressed to more comprehensively understand the full scope of stretching effects.展开更多
Myalgic encephalomyelitis/chronic fatigue syndrome-an insidious disease:The recent COVID-19 pandemic has brought substantial attention to the overlapping symptoms between long COVID and myalgic encephalomyelitis/chron...Myalgic encephalomyelitis/chronic fatigue syndrome-an insidious disease:The recent COVID-19 pandemic has brought substantial attention to the overlapping symptoms between long COVID and myalgic encephalomyelitis/chronic fatigue syndrome(ME/CFS),a chronic and poorly understood neurological disorder(Shankar et al.,2024).展开更多
Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a ...Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a myriad of factors during exercise, termed "myokines". The purpose of this study was to examine the effects of high-intensity interval training(HIIT) on the acute regulation of the mRNA expression of several myokines, including the prototypical myokine interleukin-6(IL-6), and recently identified myokines fibronectin type III domain-containing protein 5(FNDC5)(irisin) and meteorin-like protein(METRNL).Methods: Both before and after a 20-day period of twice-daily high-volume HIIT, 9 healthy males(20.5 ± 1.5 years performed a standardized bout of high-intensity interval exercise(HIIE; 5 × 4 min at ~80% pretraining peak power output) with skeletal muscle biopsy samples(vastus lateralis) obtained at rest, immediately following exercise, and at 3 h recovery.Results: Before training, a single bout of HIIE increased IL-6(p < 0.05) and METRNL(p < 0.05) mRNA expression measured at 3 h recovery when compared to rest. Following 20 days of HIIT, IL-6 and FNDC5 mRNA were increased at 3 h recovery from the standardized HIIE bout when compared to rest(both p < 0.05). Resting METRNL and FNDC5 mRNA expression were higher following training(p < 0.05), and there was an overall increase in FNDC5 mRNA post-training(main effect of training, p < 0.05).Conclusion: In human skeletal muscle(1) an acute bout of HIIE can induce upregulation of skeletal muscle IL-6 mRNA both before and after a period of intensified HIIT;(2) Resting and overall FNDC5 mRNA expression is increased by 20 days of HIIT; and(3) METRNL mRNA expression is responsive to both acute HIIE and short-term intense HIIT. Future studies are needed to confirm these findings at the protein and secretion level in humans.展开更多
AIM To examine the effect of combined exercise on colonic transit time(CTT) in admitted psychiatric patients. METHODS Over a 6-mo period, consecutive in patients with mental illness were recruited from the Somang Hosp...AIM To examine the effect of combined exercise on colonic transit time(CTT) in admitted psychiatric patients. METHODS Over a 6-mo period, consecutive in patients with mental illness were recruited from the Somang Hospital Psychiatry Unit. A combined exercise program that included 60 min per day of exercise 3 d per week for 12 wk was performed. Physical fitness and CTT of the patients were measured twice before and twice after the exercise program. CTT was measured using a multiple marker technique with a radio-opaque marker. Changes in the exercising patients' CTT and weight-,cardiovascular-and fitness-related parameters were statistically assessed.RESULTS After the 12-wk combined exercise intervention, decreased intestinal transit time was observed in all CTTs of the exercise group, including the right CTT(exercise: 15.6 ± 15.2 vs 9.2 ± 11.9, control: 13.1 ± 10.4 vs 10.9 ± 18.7), left CTT(exercise: 19.7 ± 23.5 vs 10.4 ± 13.2, control: 19.2 ± 19.0 vs 16.9 ± 19.8), recto-sigmoid CTT(exercise: 14.3 ± 16.7 vs 6.7 ± 7.9, control: 15.0 ± 14.4 vs 19.3 ± 30.3), and total colonic transit time(TCTT)(exercise: 50.2 ± 38.1 vs 27.1 ± 28.0, control: 47.4 ± 34.6 vs 47.3 ± 47.3). After the 12-wk combined exercise period, TCTT was significantly shortened in the exercise group compared with that in the control group. In addition to eating habits, water intake, and fiber intake, the increased physical activity level as a result of the 12-wk combined exercise program reduced the CTT.展开更多
Purpose: The purpose of this study was to examine, using meta-analytic measures, the evidence regarding the optimal exercise intensity at which improvements in speed of cognitive function are triggered. Specifically,...Purpose: The purpose of this study was to examine, using meta-analytic measures, the evidence regarding the optimal exercise intensity at which improvements in speed of cognitive function are triggered. Specifically, it was hypothesized that the catecholamine, lactate, and ventilatory thresholds is the point at which significant improvements in speed of cognitive function are observed. Methods: We compared mean effect sizes for threshold studies and for those studies where exercise intensity was classed as moderate (40%-- 79% VO2 or equivalent) but in which the thresholds were not measured. Results: Random effects meta-analysis showed significant, moderate, mean effect sizes for studies at the threshold (g = 0.58, Z = 2.98, p 〈 0.003) and for those during moderate intensity exercise but in which the threshold was not measured ( g = 0.54, Z = 5.0l, p 〈 0.001). There was no significant difference between mean effect sizes, which suggests that the thresholds are unlikely to represent a trigger point. Conclusion: Moderate intensity exercise, even below the thresholds, can induce improved speed of cognition, possibly due to a combination of increased peripheral catecholamine concentrations inducing vagal/nucleus tractus solitarii pathway activation and central increases due to perceptions of stress.展开更多
Objective:This study aimed to examine(1)the independent effects of hypoxia on cognitive function and(2)the effects of exercise on cognition while under hypoxia.Methods:Design:Systematic review with meta-analysis.Data ...Objective:This study aimed to examine(1)the independent effects of hypoxia on cognitive function and(2)the effects of exercise on cognition while under hypoxia.Methods:Design:Systematic review with meta-analysis.Data sources:PubMed,Scopus,Web of Science,PsychInfo,and SPORTDiscus were searched.Eligibility criteria for selecting studies:randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered(Aim 2),as were studies investigating the effects of hypoxia on cognition(Aim 1).Results:In total,18 studies met our inclusionary criteria for the systematic review,and 12 studies were meta-analyzed.Exposure to hypoxia impaired attentional ability(standardized mean difference(SMD)=-0.4),executive function(SMD=-0.18),and memory function(SMD=-0.26),but not information processing(SMD=0.27).Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement(SMD=0.3,95%confidence interval:0.14-0.45,I^2=54%,p<0.001).Various characteristics(e.g.,age,cognitive task type,exercise type,exercise intensity,training type,and hypoxia level)moderated the effects of hypoxia and exercise on cognitive function.Conclusion:Exercise during exposure to hypoxia improves cognitive function.This association appears to be moderated by individual and exercise/hypoxia-related characteristics.展开更多
Purpose: The purpose of this study was to investigate the effect of variable intensities on a simple memory recognition task during exercise.Methods: Twenty active participants took part in initial testing, a familiar...Purpose: The purpose of this study was to investigate the effect of variable intensities on a simple memory recognition task during exercise.Methods: Twenty active participants took part in initial testing, a familiarization trial and then four 60 min cycling interventions in a randomized order.Interventions consisted of no exercise(control), constant exercise at 90% ventilatory threshold(constant) and 2 trials that initially mimicked the constant trial, but then included periods of high(90% VO2peak) and low intensities(50% VO2peak). Cardiorespiratory measures and capillary blood samples were taken throughout. A short tablet-based cognitive task was completed prior to and during(50 and 55 min into exercise) each intervention.Results: The exercise conditions facilitated response time(p = 0.009), although the extent of this effect was not as strong in the variable exercise conditions(p = 0.011–0.089). High intensity exercise periods resulted in some cognitive regression back towards control trial performance.Elevations in cardiorespiratory measures and periods of hypocapnia could not explain changes in cognitive performance.Conclusion: Changes in cognitive performance with variations in exercise intensity are likely to have implications for sport and occupational settings. The timing of cognitive tests to exercise intensity changes as well as use of short cognitive assessments will be important for future work.展开更多
Background: Poor sleep quality is associated with adverse effects on health outcomes. It is not clear whether exercise can improve sleep quality and whether intensity of exercise affects any of the effects. Methods:...Background: Poor sleep quality is associated with adverse effects on health outcomes. It is not clear whether exercise can improve sleep quality and whether intensity of exercise affects any of the effects. Methods: Fifteen healthy, non-obese (body mass index = 24.4 ± 2.1 kg/m^2, mean 4- SD), sedentary (〈20 min of exercise on no more than 3 times/week) older women (66.1 ± 3.9 years) volunteered for the study. Peak oxygen consumption (VO2peak) was evaluated using a graded exercise test on a treadmill with a metabolic cart. Following a 7-day baseline period, each participant completed two exercise sessions (separated by 1 week) with equal caloric expenditure, but at different intensities (60% and 45% VO2peak, sequence randomized) between 9:00 and 11:00 am. A wrist ActiGraph monitor was used to assess sleep at baseline and two nights following each exercise session. Results: The average duration of the exercise was 54 and 72 rain, respectively at 60% (moderate-intensity) and 45% VO2peak (light-intensity). Wake time after sleep onset was significantly shorter (p = 0.016), the number of awakenings was less (p = 0.046), and total activity counts were lower (p = 0.05) after the moderate-intensity exercise compared to baseline no-exercise condition. Conclusion: Our data showed that a single moderate-intensity aerobic exercise session improved sleep quality in older women.展开更多
Purpose: The purpose of this study was to determine the effects of acute exercise on motor response inhibition using both behavioral and electrophysiological approaches. Methods: The P3 and N1 event-related potenti...Purpose: The purpose of this study was to determine the effects of acute exercise on motor response inhibition using both behavioral and electrophysiological approaches. Methods: The P3 and N1 event-related potential (ERP) components were recorded while performing a stop-signal task in 21 college students following a moderately intense acute exercise bout for 30 min and a sedentary control session that involved reading. Results: Acute exercise induced a shorter stop signal response time (SSRT) as compared to control; however, the go response time (Go RT) remained unchanged. In examining the ERP data, acute exercise increased both P3 amplitude and latency but did not affect the N1 component. Conclusion: Acute exercise has a selective and beneficial effect on cognitive function, specifically affecting the motor response inhibition aspect of executive function. Furthermore, acute exercise predominately impacts later stages of information processing during motor response inhibition, which may lead to an increase in attentional resource allocation and confer the ability to successfully withhold a response to achieve motor response inhibition.展开更多
Long-term endurance training or physical activity has been confirmed not only to improve physical performance, but to bring about an obvious beneficial effect on human health; however, the mechanism of this effect is ...Long-term endurance training or physical activity has been confirmed not only to improve physical performance, but to bring about an obvious beneficial effect on human health; however, the mechanism of this effect is not clear. The most studied health adaptations in skeletal muscle response to endurance exercise are increased muscle glycogen level and insulin sensitivity, fiber type transformation toward oxidative myofibers, and increased mitochondrial content/function. Mitochondria are dynamic organelles in eukaryotic cells critical in physical performance and disease occurrence. The mitochondrial life cycle spans biogenesis, maintenance, and clearance. Exercise training may promote each of these processes and confer positive impacts on skeletal muscle contractile and metabolic functions. This review focused on the regulation of these processes by endurance exercise and discussed its potential benefits in health and disease. We presented evidence suggesting that exercise training potentiates not only the biogenesis of mitochondria but also the removal of old and unhealthy mitochondria through mitochondrial quality control.展开更多
MicroRNAs(miRs)are small regulatory RNA transcripts capable of post-transcriptional silencing of mRNA messages by entering a cellular bimolecular apparatus called RNA-induced silencing complex.miRs are involved in the...MicroRNAs(miRs)are small regulatory RNA transcripts capable of post-transcriptional silencing of mRNA messages by entering a cellular bimolecular apparatus called RNA-induced silencing complex.miRs are involved in the regulation of cellular processes producing,eliminating or repairing the damage caused by reactive oxygen species,and they are active players in redox homeostasis.Increased mitochondrial biogenesis,function and hypertrophy of skeletal muscle are important adaptive responses to regular exercise.In the present review,we highlight some of the redox-sensitive regulatory roles of miRs.展开更多
Mitochondrial redox metabolism has long been recognized as being central to the effects of aging and the development of age-related pathologies in the major oxidative organs. Consistent evidence has shown that exercis...Mitochondrial redox metabolism has long been recognized as being central to the effects of aging and the development of age-related pathologies in the major oxidative organs. Consistent evidence has shown that exercise is able to retard the onset and impede the progression of aging by modifying mitochondrial oxidant--antioxidant homeostasis. Here we provide a broad overview of the research evidence showing the relationship between mitochondrial redox metabolism, aging and exercise. We address part aspects of mitochondrial reactive oxygen species (ROS) metabolism, from superoxide production to ROS detoxification, especially antioxidant enzymes and uncoupling protein. Furthermore, we describe mitochondrial remodeling response to aging and exercise, which is accompanied by bioenergetics and redox regulation. In addition, potential mechanisms for redox signaling involved in mitochondrial remodeling and redox metabolism regulation are also reviewed.展开更多
The discovery that endurance exercise is associated with oxidative stress was first reported in 1978.In the ensuing 4 decades,many studies confirmed this original observation.Recent investigations provided mechanistic...The discovery that endurance exercise is associated with oxidative stress was first reported in 1978.In the ensuing 4 decades,many studies confirmed this original observation.Recent investigations provided mechanistic insight into the sites of reactive oxygen species(ROS)production during exercise and the cellular consequences of an increase in ROS production.In this special topic of the Journal of Sport and Health Science,we feature 4 state-of-the-art reviews on key topics linking exercise and oxidative stress.展开更多
Background:Patients undergoing dialysis have high mortality rates and a unique risk factor profile. Some improvements elicited by exercise training have been shown in dialysis populations, here we aimed to further exp...Background:Patients undergoing dialysis have high mortality rates and a unique risk factor profile. Some improvements elicited by exercise training have been shown in dialysis populations, here we aimed to further explore the bene-fits of exercise. As well as changes in physical fitness we quantified cardiac function, depression, serum biochemistry, dialysis adequacy and energy intake following exercise training in people with chronic kidney disease (CKD) undertaking dialysis. Methods:A systematic literature search was completed in December 2012 identifying randomized, controlled trials of exercise training studies in haemodialysis (HD) patients. A subsequent meta-analysis was conducted.Results: Twenty four studies were included, totalling 879 patients. Exercise training produced significant improvements in physical fitness: peak VO2 5.03 mlO2·kg-1·min-1 (95% CI 3.73, 6.33, p 0.0001), Knee extensor strength 2.99 kg (95% CI 0.46, 5.52, p = 0.02) and 6 minute walk distance 60.7 metres (95% CI 18.9, 103, p = 0.004). Significant increases in energy intake MD 238 Kcal·day-1 (95% CI 94, 383, p = 0.001), serum Interleukin-6 MD-0.58 pg·ml-1 (95% CI-1.01, -0.15, p = 0.008) and Creactive protein MD 0.92 mg/L-1 (95% CI 0.29, 1.56, p = 0.004), but not Albumin or BMI, were reported. Improved Beck Depression scores were reported MD-6.9 (95% CI-9.7,-4.1, p 0.00001). Dialysis adequacy was reduced MD-0.23 (95% CI -0.29, -0.17, p 0.00001), while serum potassium was higher MD 0.14 mmol·L-1 (95% CI 0.01, 0.27, p = 0.04). Moreover exercise training appeared safe, with no direct exercise-associated deaths in over 30,000 patient-hours. Conclusions: Our pooled analyses confirmed improvements in physical fitness following exercise training and suggested additional improvements in dialysis efficiency (kt/v), serum potassium, inflammation and depression in HD patients.展开更多
Self-selected exercise intensity can be a useful exercise prescription tool for older adults;however, it is not known if it can elicit improvements in walking and aerobic capacity. In older adults, effects of concentr...Self-selected exercise intensity can be a useful exercise prescription tool for older adults;however, it is not known if it can elicit improvements in walking and aerobic capacity. In older adults, effects of concentric or eccentric endurance exercise at self-selected walking speed were examined on 1-mile indoor walk performance, predicted maximum oxygen uptake and physiological parameters. Twenty-four older adults (67 ± 4 years) completed 3 × 30 min treadmill walks per week for 12-weeks on level (LTW, n = 11, 0%) or downhill (DTW, n = 13, ﹣10%) treadmill gradient at a self- selected speed, which progressed every 4 weeks. Maximal oxygen uptake was predicted using a 1-mile walk at 4-week intervals with physiological responses recorded using a portable metabolic system. One-mile walking speed increased from baseline following 8- and 12-weeks (12 weeks: LTW: 13% ± 6%, DTW: 14% ± 9%,展开更多
Background:Hormone sensitive lipase(HSL) is an enzyme that regulates adipose tissue lipolysis and plays an important role in chronic exerciseinduced changes in adipose tissue metabolism.The purpose of this study was t...Background:Hormone sensitive lipase(HSL) is an enzyme that regulates adipose tissue lipolysis and plays an important role in chronic exerciseinduced changes in adipose tissue metabolism.The purpose of this study was to determine whether aerobic exercise intensity influences abdominal adipose tissue HSL gene expression in obese women under weight loss. Methods:Thirty women(body mass index(BMI) = 33.0±0.7 kg/m^2,age = 58±1 years) completed one of three 20-week interventions: caloric restriction alone(CR only,n = 8),CR plus moderate-intensity exercise(CR + moderate-intensity,45%—50%heart rate reserve(HRR). 3 day/week,n = 9),or CR plus vigorous-intensity exercise(CR + vigorous-intensity,70%—75%HRR,3 day/week,n = 13).Each group had a similar prescribed energy deficit comprised of underfeeding alone(2800 kcal/week for CR only) or underfeeding(2400 kcal/week) plus exercise(400 kcal/week).Body composition and maximal aerobic capacity(VO_2max) were measured,and subcutaneous abdominal adipose tissue samples were collected before and after the interventions.Adipose tissue HSL gene expression was measured by real time reversetranscriptase polymerase chain reaction. Results:All three interventions reduced body weight,fat mass,percent fat.and waist to a similar degree(all p < 0.01).In addition,all interventions did not change absolute VO_2 max,but increased relative VO_2 max(p < 0.05 to P < 0.01).Compared to pre-intervention.neither CR only nor CR + moderate-intensity changed adipose tissue HSL gene expression,but CR + vigorous-intensity significantly increased adipose tissue HSL gene expression(p < 0.01).The changes of HSL gene expression levels in the CR + vigorous-intensity group were significantly different from those in the CR only(p < 0.05) and CR + moderate-intensity(p < 0.01) groups.In the whole cohort,changes in adipose tissue HSL gene expression correlated positively to changes in absolute(r = 0.55,p < 0.01) and relative(r = 0.32,p = 0.09) VO_2 max. Conclusion:These results support a potential effect of aerobic exercise training intensity on hormone sensitive lipase pathway in adipose tissue metabolism in obese women under weight loss.展开更多
Type 2 diabetes(T2D)is a complex and multifaceted condition clinically characterized by high blood glucose.The management of T2D requires a holistic approach,typically involving a combination of pharmacological interv...Type 2 diabetes(T2D)is a complex and multifaceted condition clinically characterized by high blood glucose.The management of T2D requires a holistic approach,typically involving a combination of pharmacological interventions as well as lifestyle changes,such as incorporating regular exercise,within an overall patient-centred approach.However,several condition-specific and contextual factors can modulate the glucoregulatory response to acute or chronic exercise.In an era of precision medicine,optimizing exercise prescription in an effort to maximize glucose lowering effects holds promise for reducing the risk of T2D complications and improving the overall quality of life of individuals living with this condition.Reflecting on the main pathophysiological features of T2D,we review the evidence to highlight how factors related to exercise prescription can be modulated to target improved glucose control in T2D,including the frequency,intensity,total volume,and timing(e.g.,pre-vs.post-prandial)of exercise,as well as exercise modality(e.g.,aerobic vs.resistance training).We also propose a step-by-step,general framework for clinicians and practitioners on how to personalize exercise prescription to optimize glycemic control in individuals living with T2D.展开更多
文摘BRICS is the acronym for an international association of 5 major emerging national economies: Brazil, Russia, India, China, and South Africa.According to the World Economic Forum, the BRICS economies are the most competitive among all cotmtries and are distinguished by their significant regional and global influence. The health and wellness of the people within these countries is a primary agenda item of these governments for connecting their fast economic growth and the need to provide a better quality of life. As of 2015, BRICS countries represent 〉3.6 billion people or one-half of the world population. All 5 countries are members of the top 25 countries of the world by population and 4 of these cotmtries make the top 10 on this list.
基金supported by funding provided to BJG from the Natural Sciences and Engineering Research Council of Canada(NSERCgrant no.402635).
文摘Objectives:Aerobic exercise training can increase skeletal muscle mitochondrial content.Supine exercise training with legs above the heart potentially augments these increases.However,the impact of supine exercise training on mitochondrial biogenesis and cardiovascular adaptations remains unclear.Methods:In this single-centred,randomized,parallel arm trial,19 recreationally active individuals underwent seven sessions of either supine with legs up(SUP;n=9,6 females)or upright with legs down(UP;n=10,7 females)aerobic training on a recumbent bike at 71±7%and 71±2%of peak work rate(WRpeak),respectively.The study aimed to test the effects of training with decreased muscle oxygenation on indices of muscle mitochondrial remodelling.Secondary outcomes included exercise performance,muscle oxygenation,and cardiovascular responses.Results:Secondary outcomes revealed significant interaction effects for time to fatigue(TTF)and WRpeak in the SUP group during supine testing,suggesting enhanced exercise tolerance and performance.No between group interaction effects were observed for upright testing.No clear effects on mitochondrial biogenesis were observed based on expression of mitochondrial protein subunits and transcriptional regulators.Acutely,HRpeak was lower during the SUP Test compared to the UP Test.No central cardiovascular adaptations were observed following training.Conclusions:Our exploratory analyses showed that supine aerobic training more effectively improves supine exercise tolerance and performance compared with upright training,despite no differences in measured proteins related to mitochondrial biogenesis.Further research is needed to elucidate the mechanisms underlying these postural-specific training effects.Registration:clinicaltrials.gov:NCT04151095.
文摘Background:Stretching has wide appeal,but there seems to exist some mismatch between its purported applications and what the evidence shows.There is compelling evidence for some stretching applications,but for others,the evidence seems heterogeneous or unsupportive.The discrepancies even affect some systematic reviews,possibly due to heterogeneous eligibility criteria and search strategies.This consensus paper seeks to unify the divergent findings on stretching and its implications for both athletic performance and clinical practices by delivering evidence-based recommendations.Methods:A panel of 20 experts with a blend of practical experience and scholarly knowledge was assembled.The panel meticulously reviewed existing systematic reviews,defined key terminologies(e.g.,consensus definitions for different stretching modes),and crafted guidelines using a Delphi consensus approach(minimum required agreement:80%).The analysis focused on 8 topics,including stretching's acute and chronic(long-term)effects on range of motion,strength performance,muscle hypertrophy,stiffness,injury prevention,muscle recovery,posture correction,and cardiovascular health.Results:There was consensus that chronic and acute stretching(a)improves range of motion(although alternatives exist)and(b)reduces muscle stiffness(which may not always be desirable);the panel also agreed that chronic stretching(c)may promote vascular health,but more research is warranted.In contrast,consensus was found that stretch training does not(a)contribute substantively to muscle growth,(b)serve as an allencompassing injury prevention strategy,(c)improve posture,or(d)acutely enhance post-exercise recovery.Conclusion:These recommendations provide guidance for athletes and practitioners,highlighting research gaps that should be addressed to more comprehensively understand the full scope of stretching effects.
基金supported by the Judith Jane Mason and Harold Stannett Williams Memorial Foundation National Medical Program(#Mason2210)to JX。
文摘Myalgic encephalomyelitis/chronic fatigue syndrome-an insidious disease:The recent COVID-19 pandemic has brought substantial attention to the overlapping symptoms between long COVID and myalgic encephalomyelitis/chronic fatigue syndrome(ME/CFS),a chronic and poorly understood neurological disorder(Shankar et al.,2024).
基金supported by a Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant (No. RGPIN 435807-13) to JPLthe ANZ-MASON foundation (to DB)supported by a Canadian Institutes of Health Research (CIHR) New Investigator Award (No. MSH-141980)
文摘Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a myriad of factors during exercise, termed "myokines". The purpose of this study was to examine the effects of high-intensity interval training(HIIT) on the acute regulation of the mRNA expression of several myokines, including the prototypical myokine interleukin-6(IL-6), and recently identified myokines fibronectin type III domain-containing protein 5(FNDC5)(irisin) and meteorin-like protein(METRNL).Methods: Both before and after a 20-day period of twice-daily high-volume HIIT, 9 healthy males(20.5 ± 1.5 years performed a standardized bout of high-intensity interval exercise(HIIE; 5 × 4 min at ~80% pretraining peak power output) with skeletal muscle biopsy samples(vastus lateralis) obtained at rest, immediately following exercise, and at 3 h recovery.Results: Before training, a single bout of HIIE increased IL-6(p < 0.05) and METRNL(p < 0.05) mRNA expression measured at 3 h recovery when compared to rest. Following 20 days of HIIT, IL-6 and FNDC5 mRNA were increased at 3 h recovery from the standardized HIIE bout when compared to rest(both p < 0.05). Resting METRNL and FNDC5 mRNA expression were higher following training(p < 0.05), and there was an overall increase in FNDC5 mRNA post-training(main effect of training, p < 0.05).Conclusion: In human skeletal muscle(1) an acute bout of HIIE can induce upregulation of skeletal muscle IL-6 mRNA both before and after a period of intensified HIIT;(2) Resting and overall FNDC5 mRNA expression is increased by 20 days of HIIT; and(3) METRNL mRNA expression is responsive to both acute HIIE and short-term intense HIIT. Future studies are needed to confirm these findings at the protein and secretion level in humans.
文摘AIM To examine the effect of combined exercise on colonic transit time(CTT) in admitted psychiatric patients. METHODS Over a 6-mo period, consecutive in patients with mental illness were recruited from the Somang Hospital Psychiatry Unit. A combined exercise program that included 60 min per day of exercise 3 d per week for 12 wk was performed. Physical fitness and CTT of the patients were measured twice before and twice after the exercise program. CTT was measured using a multiple marker technique with a radio-opaque marker. Changes in the exercising patients' CTT and weight-,cardiovascular-and fitness-related parameters were statistically assessed.RESULTS After the 12-wk combined exercise intervention, decreased intestinal transit time was observed in all CTTs of the exercise group, including the right CTT(exercise: 15.6 ± 15.2 vs 9.2 ± 11.9, control: 13.1 ± 10.4 vs 10.9 ± 18.7), left CTT(exercise: 19.7 ± 23.5 vs 10.4 ± 13.2, control: 19.2 ± 19.0 vs 16.9 ± 19.8), recto-sigmoid CTT(exercise: 14.3 ± 16.7 vs 6.7 ± 7.9, control: 15.0 ± 14.4 vs 19.3 ± 30.3), and total colonic transit time(TCTT)(exercise: 50.2 ± 38.1 vs 27.1 ± 28.0, control: 47.4 ± 34.6 vs 47.3 ± 47.3). After the 12-wk combined exercise period, TCTT was significantly shortened in the exercise group compared with that in the control group. In addition to eating habits, water intake, and fiber intake, the increased physical activity level as a result of the 12-wk combined exercise program reduced the CTT.
文摘Purpose: The purpose of this study was to examine, using meta-analytic measures, the evidence regarding the optimal exercise intensity at which improvements in speed of cognitive function are triggered. Specifically, it was hypothesized that the catecholamine, lactate, and ventilatory thresholds is the point at which significant improvements in speed of cognitive function are observed. Methods: We compared mean effect sizes for threshold studies and for those studies where exercise intensity was classed as moderate (40%-- 79% VO2 or equivalent) but in which the thresholds were not measured. Results: Random effects meta-analysis showed significant, moderate, mean effect sizes for studies at the threshold (g = 0.58, Z = 2.98, p 〈 0.003) and for those during moderate intensity exercise but in which the threshold was not measured ( g = 0.54, Z = 5.0l, p 〈 0.001). There was no significant difference between mean effect sizes, which suggests that the thresholds are unlikely to represent a trigger point. Conclusion: Moderate intensity exercise, even below the thresholds, can induce improved speed of cognition, possibly due to a combination of increased peripheral catecholamine concentrations inducing vagal/nucleus tractus solitarii pathway activation and central increases due to perceptions of stress.
基金supported by grants from the National Natural Science Foundation of China(Grant#31671150)Guangdong Province Key Project(Grant#2018B030335001).
文摘Objective:This study aimed to examine(1)the independent effects of hypoxia on cognitive function and(2)the effects of exercise on cognition while under hypoxia.Methods:Design:Systematic review with meta-analysis.Data sources:PubMed,Scopus,Web of Science,PsychInfo,and SPORTDiscus were searched.Eligibility criteria for selecting studies:randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered(Aim 2),as were studies investigating the effects of hypoxia on cognition(Aim 1).Results:In total,18 studies met our inclusionary criteria for the systematic review,and 12 studies were meta-analyzed.Exposure to hypoxia impaired attentional ability(standardized mean difference(SMD)=-0.4),executive function(SMD=-0.18),and memory function(SMD=-0.26),but not information processing(SMD=0.27).Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement(SMD=0.3,95%confidence interval:0.14-0.45,I^2=54%,p<0.001).Various characteristics(e.g.,age,cognitive task type,exercise type,exercise intensity,training type,and hypoxia level)moderated the effects of hypoxia and exercise on cognitive function.Conclusion:Exercise during exposure to hypoxia improves cognitive function.This association appears to be moderated by individual and exercise/hypoxia-related characteristics.
基金the University of Canberra Research Institute for Sport and Exercise for supporting this project
文摘Purpose: The purpose of this study was to investigate the effect of variable intensities on a simple memory recognition task during exercise.Methods: Twenty active participants took part in initial testing, a familiarization trial and then four 60 min cycling interventions in a randomized order.Interventions consisted of no exercise(control), constant exercise at 90% ventilatory threshold(constant) and 2 trials that initially mimicked the constant trial, but then included periods of high(90% VO2peak) and low intensities(50% VO2peak). Cardiorespiratory measures and capillary blood samples were taken throughout. A short tablet-based cognitive task was completed prior to and during(50 and 55 min into exercise) each intervention.Results: The exercise conditions facilitated response time(p = 0.009), although the extent of this effect was not as strong in the variable exercise conditions(p = 0.011–0.089). High intensity exercise periods resulted in some cognitive regression back towards control trial performance.Elevations in cardiorespiratory measures and periods of hypocapnia could not explain changes in cognitive performance.Conclusion: Changes in cognitive performance with variations in exercise intensity are likely to have implications for sport and occupational settings. The timing of cognitive tests to exercise intensity changes as well as use of short cognitive assessments will be important for future work.
基金US National Institutes of Health Grants(K99AG031297 and RR024992)(Washington University School of Medicine Clinical Translational Science Award)
文摘Background: Poor sleep quality is associated with adverse effects on health outcomes. It is not clear whether exercise can improve sleep quality and whether intensity of exercise affects any of the effects. Methods: Fifteen healthy, non-obese (body mass index = 24.4 ± 2.1 kg/m^2, mean 4- SD), sedentary (〈20 min of exercise on no more than 3 times/week) older women (66.1 ± 3.9 years) volunteered for the study. Peak oxygen consumption (VO2peak) was evaluated using a graded exercise test on a treadmill with a metabolic cart. Following a 7-day baseline period, each participant completed two exercise sessions (separated by 1 week) with equal caloric expenditure, but at different intensities (60% and 45% VO2peak, sequence randomized) between 9:00 and 11:00 am. A wrist ActiGraph monitor was used to assess sleep at baseline and two nights following each exercise session. Results: The average duration of the exercise was 54 and 72 rain, respectively at 60% (moderate-intensity) and 45% VO2peak (light-intensity). Wake time after sleep onset was significantly shorter (p = 0.016), the number of awakenings was less (p = 0.046), and total activity counts were lower (p = 0.05) after the moderate-intensity exercise compared to baseline no-exercise condition. Conclusion: Our data showed that a single moderate-intensity aerobic exercise session improved sleep quality in older women.
基金supported in part by grants from the Ministry of Science and Technology to Yu-Kai Chang (NSC 102-2410-H-179-014-MY3)
文摘Purpose: The purpose of this study was to determine the effects of acute exercise on motor response inhibition using both behavioral and electrophysiological approaches. Methods: The P3 and N1 event-related potential (ERP) components were recorded while performing a stop-signal task in 21 college students following a moderately intense acute exercise bout for 30 min and a sedentary control session that involved reading. Results: Acute exercise induced a shorter stop signal response time (SSRT) as compared to control; however, the go response time (Go RT) remained unchanged. In examining the ERP data, acute exercise increased both P3 amplitude and latency but did not affect the N1 component. Conclusion: Acute exercise has a selective and beneficial effect on cognitive function, specifically affecting the motor response inhibition aspect of executive function. Furthermore, acute exercise predominately impacts later stages of information processing during motor response inhibition, which may lead to an increase in attentional resource allocation and confer the ability to successfully withhold a response to achieve motor response inhibition.
基金supported by research grants from the Natural Sciences Foundation of China(31110103919,81370454,31200894,31000523,30771048,30470837,31071040,and 30270638)Tianjin Municipal Sci-tech-innovation Base Project(10KJPT024)+1 种基金General Administration of Sport of China Basic Project(10B058)National Sci-tech Support Project(2012BAK21B03)
文摘Long-term endurance training or physical activity has been confirmed not only to improve physical performance, but to bring about an obvious beneficial effect on human health; however, the mechanism of this effect is not clear. The most studied health adaptations in skeletal muscle response to endurance exercise are increased muscle glycogen level and insulin sensitivity, fiber type transformation toward oxidative myofibers, and increased mitochondrial content/function. Mitochondria are dynamic organelles in eukaryotic cells critical in physical performance and disease occurrence. The mitochondrial life cycle spans biogenesis, maintenance, and clearance. Exercise training may promote each of these processes and confer positive impacts on skeletal muscle contractile and metabolic functions. This review focused on the regulation of these processes by endurance exercise and discussed its potential benefits in health and disease. We presented evidence suggesting that exercise training potentiates not only the biogenesis of mitochondria but also the removal of old and unhealthy mitochondria through mitochondrial quality control.
基金This study was supported by OTKA(112810)National Excellence Program(126823)Grants awarded to ZR.
文摘MicroRNAs(miRs)are small regulatory RNA transcripts capable of post-transcriptional silencing of mRNA messages by entering a cellular bimolecular apparatus called RNA-induced silencing complex.miRs are involved in the regulation of cellular processes producing,eliminating or repairing the damage caused by reactive oxygen species,and they are active players in redox homeostasis.Increased mitochondrial biogenesis,function and hypertrophy of skeletal muscle are important adaptive responses to regular exercise.In the present review,we highlight some of the redox-sensitive regulatory roles of miRs.
基金supported by research grants from the National Natural Science Foundation of China(No.31110103919, 31200894,31000523,30771048,30470837,31071040,and 30270638)Tianjin Municipal Sci-tech-innovation Base Project (No.10SYSYJC28400)+1 种基金Tianjin Science and Technology Planning Project(No.12JCQNJC07900)General Administration of Sport of China Basic Project(No.10B058)
文摘Mitochondrial redox metabolism has long been recognized as being central to the effects of aging and the development of age-related pathologies in the major oxidative organs. Consistent evidence has shown that exercise is able to retard the onset and impede the progression of aging by modifying mitochondrial oxidant--antioxidant homeostasis. Here we provide a broad overview of the research evidence showing the relationship between mitochondrial redox metabolism, aging and exercise. We address part aspects of mitochondrial reactive oxygen species (ROS) metabolism, from superoxide production to ROS detoxification, especially antioxidant enzymes and uncoupling protein. Furthermore, we describe mitochondrial remodeling response to aging and exercise, which is accompanied by bioenergetics and redox regulation. In addition, potential mechanisms for redox signaling involved in mitochondrial remodeling and redox metabolism regulation are also reviewed.
文摘The discovery that endurance exercise is associated with oxidative stress was first reported in 1978.In the ensuing 4 decades,many studies confirmed this original observation.Recent investigations provided mechanistic insight into the sites of reactive oxygen species(ROS)production during exercise and the cellular consequences of an increase in ROS production.In this special topic of the Journal of Sport and Health Science,we feature 4 state-of-the-art reviews on key topics linking exercise and oxidative stress.
文摘Background:Patients undergoing dialysis have high mortality rates and a unique risk factor profile. Some improvements elicited by exercise training have been shown in dialysis populations, here we aimed to further explore the bene-fits of exercise. As well as changes in physical fitness we quantified cardiac function, depression, serum biochemistry, dialysis adequacy and energy intake following exercise training in people with chronic kidney disease (CKD) undertaking dialysis. Methods:A systematic literature search was completed in December 2012 identifying randomized, controlled trials of exercise training studies in haemodialysis (HD) patients. A subsequent meta-analysis was conducted.Results: Twenty four studies were included, totalling 879 patients. Exercise training produced significant improvements in physical fitness: peak VO2 5.03 mlO2·kg-1·min-1 (95% CI 3.73, 6.33, p 0.0001), Knee extensor strength 2.99 kg (95% CI 0.46, 5.52, p = 0.02) and 6 minute walk distance 60.7 metres (95% CI 18.9, 103, p = 0.004). Significant increases in energy intake MD 238 Kcal·day-1 (95% CI 94, 383, p = 0.001), serum Interleukin-6 MD-0.58 pg·ml-1 (95% CI-1.01, -0.15, p = 0.008) and Creactive protein MD 0.92 mg/L-1 (95% CI 0.29, 1.56, p = 0.004), but not Albumin or BMI, were reported. Improved Beck Depression scores were reported MD-6.9 (95% CI-9.7,-4.1, p 0.00001). Dialysis adequacy was reduced MD-0.23 (95% CI -0.29, -0.17, p 0.00001), while serum potassium was higher MD 0.14 mmol·L-1 (95% CI 0.01, 0.27, p = 0.04). Moreover exercise training appeared safe, with no direct exercise-associated deaths in over 30,000 patient-hours. Conclusions: Our pooled analyses confirmed improvements in physical fitness following exercise training and suggested additional improvements in dialysis efficiency (kt/v), serum potassium, inflammation and depression in HD patients.
文摘Self-selected exercise intensity can be a useful exercise prescription tool for older adults;however, it is not known if it can elicit improvements in walking and aerobic capacity. In older adults, effects of concentric or eccentric endurance exercise at self-selected walking speed were examined on 1-mile indoor walk performance, predicted maximum oxygen uptake and physiological parameters. Twenty-four older adults (67 ± 4 years) completed 3 × 30 min treadmill walks per week for 12-weeks on level (LTW, n = 11, 0%) or downhill (DTW, n = 13, ﹣10%) treadmill gradient at a self- selected speed, which progressed every 4 weeks. Maximal oxygen uptake was predicted using a 1-mile walk at 4-week intervals with physiological responses recorded using a portable metabolic system. One-mile walking speed increased from baseline following 8- and 12-weeks (12 weeks: LTW: 13% ± 6%, DTW: 14% ± 9%,
基金supported by NIH grants R01-AG/ DK20583,P30-AG21332,and M01-RR07122
文摘Background:Hormone sensitive lipase(HSL) is an enzyme that regulates adipose tissue lipolysis and plays an important role in chronic exerciseinduced changes in adipose tissue metabolism.The purpose of this study was to determine whether aerobic exercise intensity influences abdominal adipose tissue HSL gene expression in obese women under weight loss. Methods:Thirty women(body mass index(BMI) = 33.0±0.7 kg/m^2,age = 58±1 years) completed one of three 20-week interventions: caloric restriction alone(CR only,n = 8),CR plus moderate-intensity exercise(CR + moderate-intensity,45%—50%heart rate reserve(HRR). 3 day/week,n = 9),or CR plus vigorous-intensity exercise(CR + vigorous-intensity,70%—75%HRR,3 day/week,n = 13).Each group had a similar prescribed energy deficit comprised of underfeeding alone(2800 kcal/week for CR only) or underfeeding(2400 kcal/week) plus exercise(400 kcal/week).Body composition and maximal aerobic capacity(VO_2max) were measured,and subcutaneous abdominal adipose tissue samples were collected before and after the interventions.Adipose tissue HSL gene expression was measured by real time reversetranscriptase polymerase chain reaction. Results:All three interventions reduced body weight,fat mass,percent fat.and waist to a similar degree(all p < 0.01).In addition,all interventions did not change absolute VO_2 max,but increased relative VO_2 max(p < 0.05 to P < 0.01).Compared to pre-intervention.neither CR only nor CR + moderate-intensity changed adipose tissue HSL gene expression,but CR + vigorous-intensity significantly increased adipose tissue HSL gene expression(p < 0.01).The changes of HSL gene expression levels in the CR + vigorous-intensity group were significantly different from those in the CR only(p < 0.05) and CR + moderate-intensity(p < 0.01) groups.In the whole cohort,changes in adipose tissue HSL gene expression correlated positively to changes in absolute(r = 0.55,p < 0.01) and relative(r = 0.32,p = 0.09) VO_2 max. Conclusion:These results support a potential effect of aerobic exercise training intensity on hormone sensitive lipase pathway in adipose tissue metabolism in obese women under weight loss.
文摘Type 2 diabetes(T2D)is a complex and multifaceted condition clinically characterized by high blood glucose.The management of T2D requires a holistic approach,typically involving a combination of pharmacological interventions as well as lifestyle changes,such as incorporating regular exercise,within an overall patient-centred approach.However,several condition-specific and contextual factors can modulate the glucoregulatory response to acute or chronic exercise.In an era of precision medicine,optimizing exercise prescription in an effort to maximize glucose lowering effects holds promise for reducing the risk of T2D complications and improving the overall quality of life of individuals living with this condition.Reflecting on the main pathophysiological features of T2D,we review the evidence to highlight how factors related to exercise prescription can be modulated to target improved glucose control in T2D,including the frequency,intensity,total volume,and timing(e.g.,pre-vs.post-prandial)of exercise,as well as exercise modality(e.g.,aerobic vs.resistance training).We also propose a step-by-step,general framework for clinicians and practitioners on how to personalize exercise prescription to optimize glycemic control in individuals living with T2D.