Acute effect of physical activity on academic outcomes in school-aged youth: A systematic review and multivariate meta-analysis.

BACKGROUND: There has been an increase in the number of studies examining the effect of acute and chronic physical activity on academic outcomes in children and adolescents in the last two decades. We aimed to systematically determine the acute effects of physical activity on academic outcomes in school-aged youth and to examine possible moderators. METHODS: We conducted a systematic search using PubMed, Web of Science, SPORTDiscus, and PsycINFO databases (from inception to 11th January 2023) for studies assessing the acute effects of physical activity on academic performance-related outcomes in school-aged youth. A univariate and multivariate meta-analysis was conducted based on a random-effects model with restricted maximum likelihood used to pool the academic outcomes results (Hedge's g). RESULTS: We included 11 articles (803 children and adolescents [range: 6-16 years]) in the systematic review. Overall, acute physical activity increased academic outcomes (Hedge's g = 0.35, 95% CI: 0.20-0.50). Multivariate meta-analyses revealed that physical activity increased academic performance in mathematics (Hedge's g = 0.29, 95% CI: 0.16-0.42) and language (Hedge's g = 0.28, 95% CI: 0.09-0.47). Only behavior change techniques (Hedge's g = 0.54, 95% CI, 0.18-0.90, p < 0.001) played a significant role in this relationship. CONCLUSIONS: A single bout of physical activity can improve academic outcomes in school-aged youth, which may serve as a complementary tool for the educational field. However, the observed heterogeneity in the results indicates that we should interpret the findings obtained with caution.

Physical activity, chronic kidney disease, and cardiovascular risk: A study in half a million adults.

OBJECTIVE: There is a growing prevalence of chronic kidney disease (CKD), a condition associated with a higher cardiovascular disease (CVD) risk. We assessed the association between self-reported physical activity (PA) and CKD and also studied whether PA attenuates CKD-associated CVD risk. METHODS: A cohort of Spanish adults (18-64 years) participated in this nationwide study. Participants were categorized at baseline as being either inactive (performing no PA), regularly, or insufficiently active (meeting or not, respectively, international PA recommendations) and were followed for up to 5 years. The presence of CKD (estimated glomerular filtration rate <60 mL/min/1.73 m2 ) and major CVD risk factors (diabetes, hypercholesterolemia, hypertension, obesity) was determined at baseline and at follow-up. RESULTS: 517 917 participants (44 ± 9 years, 67% male, CKD prevalence = 7%) were studied at baseline, with prospective analyses (median follow-up = 2 years, range = 2-5) in a subcohort of 264 581 individuals. Compared to physical inactivity, cross-sectional analyses at baseline showed that regular PA (odds ratio = 0.80; 95% confidence interval = 0.79-0.81), but not insufficient PA (1.02; 0.99-1.04) was associated with lower CKD prevalence. However, prospective analyses failed to confirm this association (p > 0.1). In turn, CKD was associated with a higher prevalence of hypertension (+3%) and diabetes (+5%) at baseline and with a greater incidence of hypertension at follow-up (+37%). Among those participants with CKD, regular PA was associated with a lower prevalence (-45% to -7%) and incidence (-38% to -4%) of all CVD risk factors. CONCLUSION: Although PA might not reduce incident CKD in the middle term (~2 years), it can attenuate the CVD risk linked to this condition.

Poor self-reported sleep is associated with risk factors for cardiovascular disease: A cross-sectional analysis in half a million adults.

BACKGROUND: Sleep is known to affect cardiovascular health, but some controversy exists on the independent association between different sleep characteristics (duration, restfulness, difficulties falling asleep) and specific risk factors for cardiovascular disease (CVD). We aimed to assess the association between self-reported sleep characteristics and the likelihood of major CVD risk factors. METHODS: Totally, 521,364 Spanish workers (32% female, 44 ± 9 years [18-64]) insured by an occupational risk prevention company participated in this nationwide cross-sectional study. Participants' sleep was considered 'poor' if they reported having ≥1 of the following conditions: excessively short (<6 h/d) or long (>9 h/d) sleep, unrestful sleep, or difficulties to fall asleep. We assessed the independent association between aforementioned sleep characteristics and the prevalence of hypertension, diabetes, hypercholesterolaemia, obesity and physical inactivity. RESULTS: Poor sleep (reported by 33% of participants) was associated with a higher likelihood of presenting all CVD risk factors individually, particularly physical inactivity (which prevalence was ~3-fold higher in the poor sleep group compared with participants reporting no sleep abnormality). In separate analyses, all the different sleep characteristics were associated with the likelihood of ≥2 CVD risk factors. Participants with optimal sleep, normal sleep duration, no difficulties falling sleep and restful sleep showed a lower total CVD risk score than their peers with poor sleep, short sleep duration, difficulties falling sleep and unrestful sleep, respectively (all p < .001). CONCLUSIONS: Poor sleep was associated with a higher likelihood of presenting major CVD risk factors. These findings might support the importance of monitoring and improving sleep patterns for primary CVD prevention.

Effects of an online home-based exercise intervention on breast cancer survivors during COVID-19 lockdown: a feasibility study.

PURPOSE: The strict lockdown implemented due the COVID-19 pandemic is generating a great impact on wellbeing and health-related quality of life (HRQoL) in people with cancer. We aimed to evaluate the efficacy and feasibility of an online home-based exercise intervention performed during a lockdown period analysing its effects on body composition, physical fitness, and HRQoL in breast cancer survivors. METHODS: Fifteen women with breast cancer receiving hormonal therapy (55.5 ± 6.7 years) were included in the study. The exercise intervention consisted of two weekly sessions of remotely supervised functional training (60 min per day) and two weekly sessions of unsupervised aerobic training (20-30 min/session; 60-85% of maximum heart rate) for a total of 16 weeks. DXA absorptiometry was used for the assessment of body composition. Functional assessment included cardiorespiratory fitness (CRF) by Rockport walking test, upper and lower body strength (grip strength, arm curl test, and chair stand test), walking speed (brisk walking test), and agility (8-foot up-and-go test). The HRQoL was evaluated with the QLQ-BR23 questionnaire. The adherence to the intervention was measured as the percentage of online classes attended. RESULTS: Rate of adherence for the online exercise intervention was 90 ± 17%. The exercise intervention induced significant (p < 0.05) improvements in physical fitness: CRF (+ 9%), right arm and lower limb strength (+ 10% and + 18%, respectively) and lower limbs lean mass (+ 2% and + 3.5% for left and right leg, respectively). CONCLUSION: This feasibility study suggests that an online home-based exercise intervention during COVID-19 lockdown could improve physical fitness and body composition in breast cancer survivors even in a context of heightened concern for future health.

Physical exercise effects on metastasis: a systematic review and meta-analysis in animal cancer models.

Physical exercise is considered a well-tolerated adjuvant therapy to mitigate cancer-related side effects, but its impact on metastasis is unclear. The present systematic review and meta-analysis aimed to summarize the evidence on the effects of exercise on metastasis in animal cancer models. A systematic search was conducted to identify controlled studies in animals analyzing the impact of exercise interventions on any marker of metastasis incidence or severity. The pooled mean differences (PMD) were calculated for those endpoints for which a minimum of three studies used the same assessment method. We also calculated the pooled odds ratio (OR) of metastases. Twenty-six articles were included in the systematic review, of which 12 could be meta-analyzed. Exercise training in murine cancer models did not significantly modify the number of metastatic foci (PMD = - 3.18; 95% confidence interval [CI] - 8.32, 1.97; p = 0.23), the weight of metastatic tumors (PMD = - 0.03; 95% CI - 0.10, 0.04; p = 0.41), or the risk of developing metastasis (OR = 0.64; 95% CI 0.10, 4.12; p = 0.64). These findings suggest that exercise has no overall influence on any marker of cancer metastasis incidence or severity in animal models. However, the wide methodological heterogeneity observed between studies might be taken into account and the potential exercise effects on metastasis development remain to be determined in pediatric tumors.

What are the effects of exercise training in childhood cancer survivors? A systematic review.

This systematic review aimed to summarize evidence on the effects of physical exercise interventions in childhood cancer survivors (CCS) who had finished anticancer therapy ≥ 1 year before the study. Relevant articles were identified in the electronic databases PubMed, Web of Science, and SPORTDiscus (from inception to June 27, 2019). The PEDro scale was used to assess methodological quality. Twelve studies including 109 CCS met all inclusion criteria and were included in the systematic review. The quality of the included studies was overall low. Physical exercise improved endothelial function, reduced waist circumference, and waist-to-hip ratio and increased physical activity levels. Preliminary evidence was found regarding benefits on brain volume and structure after exercise interventions in childhood brain tumor survivors. Only two studies reported exercise-related adverse events. Physical exercise seems to be safe and effective for improving several health markers in CCS, but further high-quality research and especially randomized controlled trials are needed to confirm these results.

Exercise training effects on natural killer cells: a preliminary proteomics and systems biology approach.

BACKGROUND: Regular exercise, particularly moderate-intensity continuous training (MICT), can improve immune function. Natural killer (NK) cells, a subset of lymphocytes that react to infections, are the most responsive innate immune cells to exercise, but the mechanisms underlying this are poorly understood. A type of exercise training that is gaining popularity in recent years is high-intensity interval training (HIIT), but how it affects NK cells is largely unknown. In fact, intense exercise has been traditionally viewed as a potential stressor to immune homeostasis. The purpose of this study was to determine in healthy, previously untrained adults (N=8 [3 male; 40±6 years]) the effects of an intervention consisting of 4-week MICT followed by 4-week HIIT on NK cells as compared with a pre-training (baseline) state. METHODS: Participants were studied at three time points: baseline, mid-intervention (after MICT), and post-intervention (after HIIT). Main assessments included cytotoxicity assays, flow-cytometry analysis of NK cell surface markers, and interrogation of the cellular proteome using a systems biology approach. RESULTS: A significant time effect was found for NK cell cytotoxicity (p<0.001), which was increased ~10-fold at both midand post-intervention versus baseline. No significant intervention effect was found for NK surface receptor expression, except for CXCR3 determined as mean fluorescence intensity (p=0.044, although with no significant differences in post hoc pairwise comparisons). The proteins showing a higher differential expression (Log2 fold-change > 10 and false discovery rate [FDR] q-value < 0.001) were COP9 signalosome subunit 3 (COPS3), DnaJ heat shock protein family member B11 (DNAJB11), histidyl-TRNA synthetase 1 (HARS), NIMA related kinase 9 (NEK9), nucleoporin 88 (NUP88), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), regulator of chromosome condensation 2 (RCC2), TAO kinase 3 (TAOK3), transducin beta like 2 (TBL2), and ring finger protein 40 (RNF40). All were upregulated at mid-intervention compared with baseline, with the exception of HARS, which was downregulated. Four enriched pathways (FDR p<25%) were found: two related to transmembrane transport and cellular composition (downregulated at mid-intervention vs baseline), and two related to oxidation- reduction reactions (regulated at post-intervention versus baseline). CONCLUSION: A progressive exercise intervention of MICT followed by HIIT induces a remarkable improvement in NK function compared with the untrained state, although at the mechanistic level the pathways involved seem to differ over time during the intervention.

Effects of a resistance training program in kidney transplant recipients: A randomized controlled trial.

Kidney transplant recipients are at risk of developing important adverse effects after transplantation. The objective of this study was to investigate the effects of a 10-week supervised resistance exercise-based intervention in kidney transplant recipients. Sixteen participants were randomized to a training (n = 8, 49.7 ± 9.6 years) or control group (n = 8, 48.6 ± 10.6 years). The primary endpoint was health-related quality of life evaluated through the Kidney Disease Quality of Life-Short Form (KDQOL-SF), which includes the 36-Item Short Form Survey (SF-36), and secondary endpoints included physical performance (6-minute walk distance [6-MWD], 60-second sit to stand test [60-STS], 8-foot up and go test, and handgrip and lower limb muscle strength), muscle mass, and biochemical parameters. Endpoints were assessed at baseline and after 10 weeks. Resistance exercise significantly increased (P < .05) some SF-36 domains and tended to induce improvements in one specific KDQOL-SF domain (P = .050). Further, exercise benefits were observed for 6-MWD (9% and 1% for the training and control groups, respectively; P < .001), handgrip strength (7% and -1%; P = .005), 60-STS repetitions (18% and -7%; P < .001), and 8-foot up and go test performance time (-5% and 6%; P = .010). No between-group differences (P > .05) were found for the remaining endpoints. There were no adverse events, musculoskeletal injuries, hypoglycemic episodes, cardiovascular events, or hospitalizations related to the intervention. In conclusion, 10 weeks of supervised resistance training is enough to improve quality of life and physical performance without side effects such as musculoskeletal injuries, hypoglycemic episodes, cardiovascular events, or hospitalizations related to the intervention in kidney transplant recipients.

Mortality from mental disorders and suicide in male professional American football and soccer players: A meta-analysis.

OBJECTIVE: To determine the risk of mortality from mental disorders and suicide in professional sports associated with repeated head impacts. METHODS: A systematic search was performed in PubMed, Web of Science, Scopus, and SPORTDiscus (since inception to June 8, 2021) to find studies comparing the incidence of mortality from mental disorders or suicide in former or active professional athletes of sports characterized by repeated head impacts vs athletes with no such exposure or the general non-athletic population. RESULTS: Seven retrospective studies of moderate-to-high quality that included data from boxers and from basketball, ice hockey, soccer, and National Football League (NFL) players, respectively (total = 27 477 athletes, 100% male) met all inclusion criteria. Former male NFL players (n = 13 217) had a lower risk of mortality from mental disorders (standard mortality rate [SMR] = 0.30; 0.12-0.77; p = 0.012) and suicide (SMR = 0.54; 0.37-0.78; p < 0.001) than the general population. This finding was also corroborated in male soccer players (n = 13,065; SMR = 0.55; 0.46-0.67; p < 0.001). Male athletes participating in sports associated with repeated head impacts (n = 18,606) had also a lower risk of all-cause, cardiovascular disease (CVD), and cancer mortality (all p < 0.01) than the general population. CONCLUSIONS: Participation of male athletes in American football or soccer at the professional level might confer a certain protective effect against mortality from mental disorders or suicide, besides its association with a lower risk of all-cause, CVD, or cancer-related mortality.

Inhospital exercise benefits in childhood cancer: A prospective cohort study.

Childhood cancer patients are at risk of developing important adverse effects, mortality and disease relapse after treatments, which has a substantial economic impact on healthcare systems. The objective of this study was to determine the effects of supervised inhospital exercise on clinical endpoints during childhood cancer treatment. 169 children with a new diagnosis of cancer were divided into an exercise intervention (n = 68, 11 ± 4 years) or a control group (n = 101, 11 ± 3 years). The cohort was followed up from the start of treatment for up to five years. Supervised inhospital exercise intervention was performed during the neoadjuvant (for solid tumors) or intensive chemotherapy treatment period (for leukemias). The median duration of the intervention was 22 (interquartile range, 14-28) weeks. We assessed survival, risk of disease relapse or metastasis, and days of hospitalization (primary outcomes), and cardiovascular function, anthropometry and blood variables (secondary outcomes). No exercise-related adverse events were noted. The exercise group had significantly less days of hospitalization than the control group (P = .031), resulting in a lower (~-17%) mean total economic cost of hospitalization in the former. Moreover, echocardiography-determined left ventricular function (ejection fraction and fractional shortening) was significantly impaired in the control group after treatment compared with baseline, whereas it was maintained in the exercise group (P = .024 and .021 for the between-group differences, respectively). In conclusion, supervised inhospital exercise intervention is safe and plays a cardioprotective role, at least in the short term, in children with cancer, also reducing hospitalization time, and therefore alleviating the economic burden.

Reply: Letter to the Editor: Exercise Interventions and Cardiovascular Health in Childhood Cancer: A Meta-Analysis.

Dear EditorWe sincerely appreciate the nice comments by Drs. P.V. da Costa Ghignatti and R. Pereira de Lima 1 concerning our recent meta-analysis assessing the effects of physical exercise interventions on cardiovascular endpoints in childhood cancer survivors 2. They are quite right to remain that even non-significant improvements in cardiorespiratory fitness (CRF) might be clinically relevant. Indeed, we still do not know if CRF increments of a theoretically low magnitude (i. e., <1 metabolic equivalent) might have a prognostic value in the context of pediatric cancer and treatment-associated cardiotoxicity. We also agree that unsupervised exercise interventions are unlikely to be as effective as tailored programs, especially because the latter allow for intensity to being adequately controlled and thus gradually increased. It is indeed our opinion, after long years of experience working with children with cancer as well as with other debilitated clinical populations, that there is always room for physiological improvement and ideally loads should be gradually improved instead of remaining stable.

Exercise Interventions and Cardiovascular Health in Childhood Cancer: A Meta-analysis.

This study analyzed the effects of physical exercise interventions on cardiovascular endpoints in childhood cancer survivors. Relevant articles were systematically searched in PubMed, CINAHL, and Web of Science databases (since inception to 11th September 2019). We performed a meta-analysis (random effects) to determine the mean difference (expressed together with 95% confidence intervals) between pre- and post-intervention values for those cardiovascular endpoints reported in more than three studies. Twenty-seven studies (of which 16 were controlled studies) comprising 697 participants were included. Only three studies reported adverse events related to exercise interventions. Exercise resulted in an increased performance on the 6-minute walk distance test (mean difference=111 m, 95% confidence interval=39-183, p=0.003) and a non-significant trend (mean difference=1.97 ml∙kg-1∙min-1, 95% confidence interval=-0.12-4.06, p=0.065) for improvement in peak oxygen uptake. Furthermore, left ventricular ejection fraction was preserved after exercise interventions (mean difference=0.29%, 95% confidence interval=-1.41-1.99, p=0.738). In summary, exercise interventions might exert a cardioprotective effect in childhood cancer survivors by improving - or attenuating the decline of - physical capacity and cardiovascular function. Further studies, particularly randomized controlled trials, are needed to confirm these benefits.

Concurrent Exercise Interventions in Breast Cancer Survivors with Cancer-related Fatigue.

This study compared the effects of two supervised concurrent training interventions in breast cancer survivors with cancer-related fatigue at baseline. Twenty-three female breast cancer survivors (50±8 years) were randomized to a high- (n=13) or a moderate-intensity (n=10) training program. Both interventions lasted 16 weeks and included the same resistance exercises, but the aerobic component was supervised and more intense in the former (i.e., rating of perceived exertion of 7-8 vs. 6 on a 1-10 scale for the high and moderate-intensity intervention, respectively). The primary endpoint was fatigue perception. Endpoints were assessed at baseline and after 16 weeks. The p-value for statistical significance was set at 0.004 after Bonferroni correction for multiple comparisons. The high-intensity training program increased lower-limb muscle strength significantly (p=0.002) and tended to improve fatigue perception (p=0.006), waist circumference (p=0.013), neutrophil-to-lymphocyte ratio (p=0.028) and some quality of life items (p=0.011). Although the moderate-intensity training program did not provide such benefits in general (i.e., higher p-values for pre vs post-intervention comparisons), no significant differences were found between interventions (all p>0.004). Further research is needed to elucidate if the benefits provided by high-intensity concurrent training are superior to those elicited by moderate-intensity training in breast cancer survivors.

Physical exercise and Prader-Willi syndrome: A systematic review.

OBJECTIVE: The aim of this systematic review was to summarize evidence on the acute responses of individuals with Prader-Willi syndrome (PWS) to physical exercise, and on the effectiveness of long-term exercise interventions to improve the clinical manifestations of this syndrome. DESIGN/METHODS: Relevant articles were identified in the electronic databases PubMed, Medline, CINAHL and SPORTDiscus (from inception to December 2018). Twenty-two studies including a total of 356 patients with PWS met all inclusion criteria and were included in the review. RESULTS: Patients with PWS present with a decreased physical performance and impaired cardiorespiratory (maximal oxygen consumption, heart rate recovery after exercise) and hormonal (growth hormone release) responses to exercise. Most long-term exercise interventions have proven to decrease body mass while improving physical performance. Some benefits have also been reported in biochemical (glucose homeostasis, lipid profile) and biomechanical (gait pattern) variables, although there is controversy regarding the effects on body composition. No exercise-related adverse events have been reported in patients with PWS. CONCLUSION: Physical exercise seems to be safe and effective for improving several phenotypes in PWS, notably physical fitness. However, further research is needed to confirm these results and especially to corroborate whether exercise per se or combined with dietary intervention is an effective coadjuvant treatment for reducing body mass in these patients.

Supplements with purported effects on muscle mass and strength.

PURPOSE: Several supplements are purported to promote muscle hypertrophy and strength gains in healthy subjects, or to prevent muscle wasting in atrophying situations (e.g., ageing or disuse periods). However, their effectiveness remains unclear. METHODS: This review summarizes the available evidence on the beneficial impacts of several popular supplements on muscle mass or strength. RESULTS: Among the supplements tested, nitrate and caffeine returned sufficient evidence supporting their acute beneficial effects on muscle strength, whereas the long-term consumption of creatine, protein and polyunsaturated fatty acids seems to consistently increase or preserve muscle mass and strength (evidence level A). On the other hand, mixed or unclear evidence was found for several popular supplements including branched-chain amino acids, adenosine triphosphate, citrulline, ß-Hydroxy-ß-methylbutyrate, minerals, most vitamins, phosphatidic acid or arginine (evidence level B), weak or scarce evidence was found for conjugated linoleic acid, glutamine, resveratrol, tribulus terrestris or ursolic acid (evidence level C), and no evidence was found for other supplements such as ornithine or α-ketoglutarate (evidence D). Of note, although most supplements appear to be safe when consumed at typical doses, some adverse events have been reported for some of them (e.g., caffeine, vitamins, α-ketoglutarate, tribulus terrestris, arginine) after large intakes, and there is insufficient evidence to determine the safety of many frequently used supplements (e.g., ornithine, conjugated linoleic acid, ursolic acid). CONCLUSION:  In summary, despite their popularity, there is little evidence supporting the use of most supplements, and some of them have been even proven ineffective or potentially associated with adverse effects.