Dynamic resistance exercise increases skeletal muscle-derived FSTL1 inducing cardiac angiogenesis via DIP2A–Smad2/3 in rats following myocardial infarction

PurposeThe aim of this study was to investigate the potential of dynamic resistance exercise to generate skeletal muscle-derived follistatin like-1 (FSTL1), which may induce cardioprotection in rats following myocardial infarction (MI) by inducing angiogenesis.MethodsMale, adult Sprague-Dawley rats were randomly divided into 5 groups (n = 12 in each group): sham group (S), sedentary MI group (MI), MI + resistance exercise group (MR), MI + adeno-associated virus (AAV)–FSTL1 injection group (MA), and MI + AAV–FSTL1 injection + resistance exercise group (MAR). The AAV–FSTL1 vector was prepared by molecular biology methods and injected into the anterior tibialis muscle. The MI model was established by ligation of the left anterior descending coronary artery. Rats in the MR and MAR groups underwent 4 weeks of dynamic resistance exercise training using a weighted climbing-up ladder. Heart function was evaluated by hemodynamic measures. Collagen volume fraction of myocardium was observed and analyzed by Masson's staining. Human umbilical vein vessel endothelial cells culture and recombinant human FSTL1 protein or transforming growth factor-β receptor 1 (TGFβR1) inhibitor treatment were used to elucidate the molecular signaling mechanism of FSTL1. Angiogenesis, cell proliferation, and disco interacting protein 2 homolog A (DIP2A) location were observed by immunofluorescence staining. The expression of FSTL1, DIP2A, and the activation of signaling pathways were detected by Western blotting. Angiogenesis of endothelial cells was observed by tubule experiment. One-way analysis of variance and Student's t test were used for statistical analysis.ResultsResistance exercise stimulated the secretion of skeletal muscle FSTL1, which promoted myocardial angiogenesis, inhibited pathological remodeling, and protected cardiac function in MI rats. Exercise facilitated skeletal muscle FSTL1 to play a role in protecting the heart. Exogenous FSTL1 promoted the human umbilical vein vessel endothelial cells proliferation and up-regulated the expression of DIP2A, while TGFβR1 inhibitor intervention down-regulated the phosphorylation level of Smad2/3 and the expression of vascular endothelial growth factor-A, which was not conducive to angiogenesis. FSTL1 bound to the receptor, DIP2A, to regulate angiogenesis mainly through the Smad2/3 signaling pathway. FSTL1–DIP2A directly activated Smad2/3 and was not affected by TGFβR1.ConclusionDynamic resistance exercise stimulates the expression of skeletal muscle-derived FSTL1, which could supplement the insufficiency of cardiac FSTL1 and promote cardiac rehabilitation through the DIP2A–Smad2/3 signaling pathway in MI rats.     

抗阻运动通过刺激骨骼肌FSTL1分泌抑制心梗大鼠心肌细胞凋亡及其机制探讨

目的:探讨抗阻运动通过刺激骨骼肌卵泡抑素样蛋白1(Follistatin-like protein 1,FSTL1)分泌,抑制心梗(Myocardial Infarction,MI)大鼠心肌细胞凋亡及其机制。方法:动物实验:结扎SD大鼠左冠状动脉前降支制备MI模型,术后随机分为5组,分别为假手术组(S)、心梗安静对照组(MI)、心梗+抗阻运动组(MR)、心梗+腺相关病毒空载体组(MV)、心梗+FSTL1腺相关病毒载体组(MF),每组10只,其中S组只穿线不结扎。术后1周,MR组进行为期4周的爬梯抗阻运动,MV组和MF组于左后肢胫骨前肌分别注射腺相关病毒空载体和FSTL1腺相关病毒载体。训练结束后次日,腹腔麻醉,测定心功能,摘取心脏和左后肢胫骨前肌。Masson染色观察并计算心肌胶原容积百分比(CVF%);TUNEL检测分析心肌细胞凋亡;Western Blotting实验测定骨骼肌和血清FSTL1蛋白含量,心肌FSTL1、DIP2A、p-Akt/Akt、p-mTOR/mTOR、Bcl2/Bax蛋白表达。细胞实验:H9C2细胞分为8组,即H9C2对照组、H9C2+LPS(脂多糖:Lipopolysaccharide,LPS)组、H9C2+LPS+AICAR(AMPK激动剂AICAR)组、H9C2+LPS+LY294002(PI3K抑制剂LY294002)组、H9C2+LPS+AICAR+LY294002组、H9C2+LPS+rhFSTL1组、H9C2+LPS+rhFSTL1+AICAR组、H9C2+LPS+rhFSTL1+LY294002组。TUNEL检测H9C2细胞凋亡,CCK8检测H9C2细胞存活率,Western Blotting实验检测细胞FSTL1、DIP2A、p-Akt/Akt、p-mTOR/mTOR、Bcl2/Bax蛋白表达。结果:MI后大鼠骨骼肌FSTL1基因和蛋白表达降低,心肌FSTL1基因表达无显著变化,心肌和血清FSTL1蛋白水平显著升高,心肌细胞凋亡和心肌纤维化显著增加,心功能下降。抗阻运动或胫骨前肌注射FSTL1腺相关病毒载体后,骨骼肌、血清和心肌FSTL1蛋白水平均显著升高,心肌FSTL1受体DIP2A、p-Akt、p-mTOR、Bcl2/Bax蛋白表达均显著上调,心肌细胞凋亡和心肌纤维化减少,心功能显著改善,且抗阻运动显著上调骨骼肌FSTL1基因表达,但心肌FSTL1基因表达无显著性差异。FSTL1和AICAR干预均显著抑制LPS诱导的H9C2细胞凋亡,增加FSTL1、DIP2A、p-Akt、p-mTOR、Bcl2/Bax蛋白表达水平和细胞存活率,LY294002干预与上述作用相反。结论:在抗阻运动上调MI大鼠心肌FSTL1表达抑制心肌细胞凋亡过程中,骨骼肌源性FSTL1发挥重要作用,骨骼肌源性FSTL1可通过血液循环到达心脏,与其受体DIP2A结合,激活下游Akt-mTOR信号通路,抑制心肌细胞凋亡,降低心肌纤维化,改善MI大鼠心功能。     

Associations of physical activity,sedentary time,and physical fitness with mental health during pregnancy: The GESTAFIT project

PurposeThis study was aimed to analyze the associations of objectively measured physical activity (PA), sedentary time, and physical fitness with mental health in the early second trimester (16 ± 2 gestational weeks) of pregnancy.MethodsFrom 229 women initially contacted, 124 pregnant women participated in the present cross-sectional study. Data were collected between November 2015 and March 2017. The participants wore Actigraph GT3X+ Triaxial accelerometers for 9 consecutive days to objectively measure their PA levels and sedentary time. A performance-based test battery was used to measure physical fitness. Self-report questionnaires assessed psychological ill-being (i.e., negative affect, anxiety, and depression), and psychological well-being (i.e., emotional intelligence, resilience, and positive affect). Linear regression analyses were adjusted for age, educational level, accelerometer wear time, miscarriages, and low back pain.ResultsModerate-to-vigorous PA was negatively associated with depression (β = –0.222, adjusted R² = 0.050, p = 0.041). Higher levels of sedentary time were negatively associated with positive affect (β = –0.260, adjusted R² = 0.085, p = 0.017). Greater upper-body flexibility was positively associated with better emotional regulation (β = 0.195, adjusted R²= 0.030, p = 0.047). The remaining associations were not significant (all p > 0.05).ConclusionAn active lifestyle characterized by higher levels of moderate-to-vigorous PA and lower levels of sedentary time during pregnancy might modestly improve the mental health of pregnant women. Although previous research has focused on the benefits of cardiorespiratory exercise, the present study shows that only upper-body flexibility is related to emotional regulation in early pregnant women. If the present findings are corroborated in further experimental research, physical exercise programs should focus on enhancing flexibility to promote improvements in emotional regulation during early second-trimester of pregnancy.     

Mediation role of cardiorespiratory fitness on the association between fatness and cardiometabolic risk in European adolescents: The HELENA study

PurposeThis study was aimed to analyze the mediation role of cardiorespiratory fitness (CRF) on the association between fatness and cardiometabolic risk scores (CMRs) in European adolescents.MethodsA cross-sectional study was conducted in adolescents (n = 525; 46% boys; 14.1 ± 1.1 years old, mean ± SD) from 10 European cities involved in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. CRF was measured by means of the shuttle run test, while fatness measures included body mass index (BMI), waist to height ratio, and fat mass index estimated from skinfold thicknesses. A clustered CMRs was computed by summing the standardized values of homeostasis model assessment, systolic blood pressure, triglycerides, total cholesterol/high-density lipoprotein cholesterol ratio, and leptin.ResultsLinear regression models indicated that CRF acted as an important and partial mediator in the association between fatness and CMRs in 12–17-year-old adolescents (for BMI: coefficients of the indirect role β = 0.058 (95% confidence interval (95%CI): 0.023–0.101), Sobel test z = 3.11 (10.0% mediation); for waist to height ratio: β = 4.279 (95%CI: 2.242–7.059), z =3.86 (11.5% mediation); and for fat mass index: β = 0.060 (95%CI: 0.020–0.106), z = 2.85 (9.4% mediation); all p < 0.01).ConclusionIn adolescents, the association between fatness and CMRs could be partially decreased with improvements to fitness levels; therefore, CRF contribution both in the clinical field and public health could be important to consider and promote in adolescents independently of their fatness levels.     

Prevalence and correlates of meeting the muscle-strengthening exercise recommendations among Chinese children and adolescents: Results from 2019 Physical Activity and Fitness in China—The Youth Study

PurposeThis study aimed to describe the national prevalence of Chinese children and adolescents who met the World Health Organization muscle-strengthening exercise (MSE) recommendations and identify correlates of meeting the MSE recommendations.MethodsCross-sectional data from the 2019 Physical Activity and Fitness in China—The Youth Study, a nationally representative sample of Chinese children and adolescents (n = 80,413; mean age = 13.7 years; 53.9% girls) and their parents, were analyzed. Children and adolescents who reported engaging ≥3 days (up to 7 days) of MSE per week were classified as meeting the MSE recommendations. MSE, demographics, lifestyle behaviors (sport participation, moderate-to-vigorous physical activity, screen time, and sleep duration), exercise intention, peer and parental support, and parental MSE participation were assessed through self-reports. Logistic regression models were used to determine the correlates of meeting the MSE recommendations. The analyses were completed in 2020.ResultsOverall, 39.3% of children and adolescents met the MSE recommendations. Girls, 10th–12th graders, minorities, those from lower income households and those from families with lower parental education were less likely to meet the MSE recommendations. Children and adolescents who were proficient in ≥2 sports were more likely to meet the MSE recommendations (adjusted odds ratio (aOR) = 1.44, 95% confidence interval (95%CI): 1.26–1.65), as were those with more moderate-to-vigorous physical activity (aOR = 1.57, 95%CI: 1.53–1.61). Additionally, children and adolescents with high exercise intention (aOR = 1.60, 95%CI: 1.51–1.69), those whose parents met the adult MSE recommendations (aOR = 1.46, 95%CI: 1.40–1.52), and those who received high peer (aOR = 1.27, 95%CI: 1.20–1.34) and parental support (aOR = 1.07, 95%CI: 1.04–1.12) were more likely to meet the MSE recommendations.ConclusionLess than two-fifths of Chinese children and adolescents met the World Health Organization MSE recommendations. The correlates identified in our study can help inform the development of school and community based strategies and policies to enhance participation in MSE and improve muscular fitness of all Chinese children and adolescents.     

The effect of acute aerobic exercise on central arterial stiffness,wave reflections,and hemodynamics in adults with diabetes: A randomized cross-over design

BackgroundIndividuals with diabetes have greater central arterial stiffness, wave reflections, and hemodynamics, all of which promote the accelerated cardiovascular pathology seen in this population. Acute aerobic exercise has been shown to be an effective strategy for reducing central arterial stiffness, wave reflections, and hemodynamics in healthy individuals; however, the effects of acute aerobic exercise in reducing these outcomes is not well established in people with diabetes. Recently, implementation of high-intensity interval exercise (HIIE) has shown superior improvements in cardiovascular health outcomes when compared to traditional aerobic exercise. Yet, the effect of HIIE on the aforementioned outcomes in people with diabetes is not known. The purpose of this study was to (i) describe the central arterial stiffness, wave reflections, and hemodynamic responses to a bout of HIIE and moderate-intensity continuous exercise (MICE) in adults with diabetes; and (ii) compare the effects of HIIE and MICE on the aforementioned outcomes.MethodsA total of 24 adult men and women (aged 29–59 years old) with type 1 (n = 12) and type 2 (n = 12) diabetes participated in a randomized cross-over study. All participants completed the following protocols: (i) HIIE: cycling for 4 × 4 min at 85%–95% of heart rate peak (HR_peak), interspersed with 3 min of active recovery at 60%–70%HR_peak; (ii) MICE: 33 min of continuous cycling at 60%–70%HR_peak; and (iii) control (CON): lying quietly in a supine position for 30 min.ResultsA significant group × time effect was found for changes in central systolic blood pressure (F = 3.20, p = 0.01) with a transient reduction for the HIIE group but not for the MICE or CON groups. There was a significant group × time effect for changes in augmentation index at a heart rate of 75 beats/min (F = 2.32, p = 0.04) with a decrease following for HIIE and MICE but not for CON. For all other measures of central arterial stiffness and hemodynamics, no significant changes were observed (p > 0.05).ConclusionA bout of HIIE appears to lead to a greater transient reduction in central systolic blood pressure than the reduction observed following MICE; however, both HIIE and MICE improved augmentation index at a heart rate of 75 beats/min in people with diabetes. There was no significant difference in response to HIIE and MICE in all outcomes. This provides preliminary evidence on the role of HIIE on such outcomes in people with diabetes.     

Sports activity patterns and cardio-metabolic health over time among adults in Germany: Results of a nationwide 12-year follow-up study

BackgroundPhysical activity is favorable for health, and vigorous sports activity is particularly beneficial. This study investigates the association between changes in sports participation patterns over time and cardio-metabolic and self-perceived health outcomes.MethodsData from 3752 adults (18–79 years of age) who participated in 2 national health interview and examination surveys in 1997–1999 and 2008–2011 were included, with a mean follow-up time of about 12 years. A change in self-reported sports activity was analyzed with respect to the incidence of type 2 diabetes, coronary heart disease (CHD), hypertension, obesity, dyslipidemia, metabolic syndrome, and poor self-perceived health. Participants with pre-existing disease or risk factor of interest at baseline were excluded from the analysis. Being sufficiently active in sports was specified as doing sports for at least 1–2 h per week, and 4 activity categories were defined: 1) inactive at both time points (inactive–inactive), 2) inactive at baseline and active at follow-up (inactive–active), 3) active at baseline and inactive at follow-up (active–inactive), and 4) active at both time points (active–active). Associations between sports activity engagement and health outcomes were estimated by logistic regression models with different stages of adjustments.ResultsNot engaging in any regular sports activity at both time points (inactive–inactive) was associated with higher rates of type 2 diabetes (odds ratio (OR) = 1.82, 95% confidence interval (95%CI): 1.08–3.08), CHD (OR = 1.82, 95%CI: 1.16–2.84), hypertension (OR = 1.36, 95%CI: 1.03–1.81), metabolic syndrome (OR = 1.58, 95%CI: 1.08–2.32), and poor self-perceived health (OR = 2.54, 95%CI: 1.83–3.53) compared to doing regular sports for a minimum of 1–2 h per week over time (active–active). In case of change from inactivity to any regular sports activity (inactive–active), the rate of risk factor occurrence was not statistically different from the active–active reference group except for poor self-perceived health, but it was higher for type 2 diabetes (OR = 2.15, 95%CI: 1.12–4.14) and CHD (OR = 1.77, 95%CI: 1.03–3.03). Being active at baseline but inactive at follow-up (active–inactive) was not associated with higher disease incidence of type 2 diabetes (OR = 0.70, 95%CI: 0.25–1.97) or CHD (OR = 1.20, 95%CI: 0.49–2.99), but was associated with higher rates of hypertension (OR = 1.61, 95%CI: 1.11–2.34), obesity (OR = 2.34, 95%CI: 1.53–3.57), metabolic syndrome (OR = 1.70, 95%CI: 1.11–2.63), and poor self-perceived health (OR = 2.16, 95%CI: 1.53–3.07) at follow-up.ConclusionEven a low weekly quantity (1–2 h) of regular sports activity is partly associated with health benefits. Being formerly but not currently active was not associated with an increased disease incidence, but was associated with a higher risk-factor development compared to the reference group (active–active). Becoming active was preventive for risk-factor development but was not preventive for disease incidence, which probably means that the health benefits from sports activity are not sustainable and disease incidence is only shifted to a later period in life. For this reason, the promotion of and commitment to regular sports activity should be addressed as early as possible over the lifespan to achieve the best health benefits.     

Tai Ji Quan as antihypertensive lifestyle therapy: A systematic review and meta-analysis

BackgroundProfessional health organizations are not currently recommending Tai Ji Quan alongside aerobic exercise to treat hypertension. We aimed to examine the efficacy of Tai Ji Quan as antihypertensive lifestyle therapy.MethodsTai Ji Quan interventions published in English and Chinese were included when they involved healthy adults, reported pre- and post-intervention blood pressure (BP), and had a non-exercise/non-diet control group. We systematically searched 11 electronic databases for studies published through July 31, 2018, yielding 31 qualifying controlled trials. We (1) evaluated the risk of bias and methodological study quality, (2) performed meta-regression analyses following random-effects assumptions, and (3) generated additive models representing the largest possible clinically relevant BP reductions.ResultsParticipants (n = 3223) were middle-aged (56.6 ± 15.1 years of age, mean ± SD) adults with prehypertension (systolic BP (SBP) = 136.9 ± 15.2 mmHg, diastolic BP (DBP) = 83.4 ± 8.7 mmHg). Tai Ji Quan was practiced 4.0 ± 1.4 sessions/week for 54.0 ± 10.6 min/session for 22.3 ± 20.2 weeks. Overall, Tai Ji Quan elicited significant reductions in SBP (–11.3 mmHg, 95%CI: –14.6 to –8.0; d₊ = –0.75) and DBP (–4.8 mmHg, 95%CI: –6.4 to –3.1; d₊ = –0.53) vs. control (p < 0.001). Controlling for publication bias among samples with hypertension, Tai Ji Quan trials published in English elicited SBP reductions of 10.4 mmHg and DBP reductions of 4.0 mmHg, which was half the magnitude of trials published in Chinese (SBP reductions of 18.6 mmHg and DBP reductions of 8.8 mmHg).ConclusionOur results indicate that Tai Ji Quan is a viable antihypertensive lifestyle therapy that produces clinically meaningful BP reductions (i.e., 10.4 mmHg and 4.0 mmHg of SBP and DBP reductions, respectively) among individuals with hypertension. Such magnitude of BP reductions can lower the incidence of cardiovascular disease by up to 40%.     

Temporal trends in 6-minute walking distance for older Japanese adults between 1998 and 2017

BackgroundThe 6-minute walking distance (6MWD) is an excellent measure of both functional endurance and health. The primary aim of this study was to estimate temporal trends in 6MWD for older Japanese adults between 1998 and 2017; the secondary aim was to estimate concurrent trends in body size (i.e., height and mass) and self-reported participation in exercise/sport.MethodsAdults aged 65–79 years were included. Annual nationally representative 6MWD data (n = 103,505) for the entire period were obtained from the Japanese Ministry of Education, Culture, Sports, Science and Technology. Temporal trends in means (and relative frequencies) were estimated at the gender–age level by best-fitting sample-weighted linear/polynomial regression models, with national trends estimated by a post-stratified population-weighting procedure. Temporal trends in distributional variability were estimated as the ratio of coefficients of variation.ResultsBetween 1998 and 2017 there was a steady, moderate improvement in mean 6MWD (absolute = 45 m (95% confidence interval (95%CI): 43–47); percent = 8.0% (95%CI: 7.6%–8.4%); effect size = 0.51 (95%CI: 0.48–0.54)). Gender- and age-related temporal differences in means were negligible. Variability in 6MWD declined substantially (ratio of coefficients of variation = 0.89, 95%CI: 0.87–0.92), with declines larger for women compared to men, and for 75–79-year-olds compared to 65–74-year-olds. Correspondingly, there were moderate and negligible increases in mean height and mass, respectively, and negligible increases in the percentage who participated in exercise/sport at least 3 days per week and at least 30 min per session.ConclusionThere has been a steady, moderate improvement in mean 6MWD for older Japanese adults since 1998, which is suggestive of corresponding improvements in both functional endurance and health. The substantial decline in variability indicates that the temporal improvement in mean 6MWD was not uniform across the distribution. Trends in 6MWD are probably influenced by corresponding trends in body size and/or participation in exercise/sport.     

Is device-measured vigorous physical activity associated with health-related outcomes in children and adolescents? A systematic review and meta-analysis

ObjectiveThis study sought to analyze the prospective association between vigorous-intensity physical activity (VPA) and health-related outcomes in children and adolescents.MethodsStudies reporting associations between device-measured VPA and health-related factors in children and adolescents aged 3–18 years were identified through database searches (MEDLINE, EMBASE, and SPORTDiscus). Correlation coefficients were pooled if outcomes were reported by at least 3 studies, using DerSimonian-Laird random effects models.ResultsData from 23 studies including 13,674 participants were pooled using random effects models. Significant associations were found between VPA at baseline and overall adiposity (r = −0.09, 95% confidence interval (95%CI): –0.15 to –0.03; p = 0.002; I² = 89.8%), cardiometabolic risk score (r = –0.13, 95%CI: –0.24 to –0.02, p = 0.020; I² = 69.6%), cardiorespiratory fitness (r = 0.25, 95%CI: 0.15−0.35; p < 0.001; I² = 57.2%), and total body bone mineral density (r = 0.16, 95%CI: 0.06 to 0.25; p = 0.001; I² = 0%).ConclusionVPA seems to be negatively related to adiposity and cardiometabolic risk score and positively related to cardiorespiratory fitness and total body bone mineral density among children and adolescents at follow-up. Therefore, our findings support the need to strengthen physical activity recommendations regarding VPA due to its health benefits in children and adolescents.     

Factors associated with concussion-symptom knowledge and attitudes toward concussion care seeking in a national survey of parents of middle-school children in the US

Background:Developing appropriate concussion prevention and management paradigms in middle school(MS)settings requires understanding parents’general levels of concussion-related knowledge and attitudes.This study examined factors associated with concussion-symptom knowledge and care-seeking attitudes among parents of MS children(aged 10-15 years).Methods:A panel of 1224 randomly selected U.S.residents,aged ≥18 years and identifying as parents of MS children,completed an online questionnaire capturing parental and child characteristics.The parents’concussion-symptom knowledge was measured using 25 questions,with possible answers being“yes”,“maybe”,and“no”.Correct answers earned 2 points,“maybe”answers earned 1 point,and incorrect answers earned 0 point(range:0-50;higher scores=better knowledge).Concussion care-seeking attitudes were also collected using five 7-point scale items(range:5-35;higher scores=more positive attitudes).Multivariable ordinal logistic regression models identified predictors of higher scores.Models met proportional odds assumptions.Adjusted odds ratios(aORs)with 95%confidence intervals(95%CIs)(excluding 1.00)were deemed statistically significant.Results:Median scores were 39(interquartile range:32-44)for symptom knowledge and 32(interquartile range:28-35)for care-seeking attitude.In multivariable models,odds of better symptom knowledge were higher in women vs.men(aOR=2.28;95%CI:1.71-3.05),white/non-Hispanics vs.other racial or ethnic groups(aOR=1.88;95%CI:1.42-2.49),higher parental age(10-year-increase aOR=1.47;95%CI:1.26-1.71),and greater competitiveness(10%-scale-increase aOR=1.24;95%CI:1.13-1.36).Odds of more positive care-seeking attitudes were higher in white/non-Hispanics vs.other racial or ethnic groups(aOR=1.45;95%CI:1.06-1.99)and in older parental age(10-year-increase aOR=1.24;95%CI:1.05-1.47).Conclusion:Characteristics of middle school children’s parents(e.g.,sex,race or ethnicity,age)are associated with their concussion-symptom knowledge and care-seeking attitudes.Parents’variations in concussion knowledge and attitudes warrant tailored concussion education and prevention.     

The relationships between step count and all-cause mortality and cardiovascular events: A dose–response meta-analysis

BackgroundA goal of 10,000 steps per day is widely advocated, but there is little evidence to support that goal. Our purpose was to examine the dose–response relationships between step count and all-cause mortality and cardiovascular disease risk.MethodsCochrane Central Register of Controlled Trials, EMBASE, OVID, PubMed, Scopus, and Web of Science databases were systematically searched for studies published before July 9, 2021, that evaluated the association between daily steps and at least 1 outcome.ResultsSixteen publications (12 related to all-cause mortality, 5 related to cardiovascular disease; and 1 article contained 2 outcomes: both all-cause death and cardiovascular events) were eligible for inclusion in the meta-analysis. There was evidence of a nonlinear dose–response relationship between step count and risk of all-cause mortality or cardiovascular disease (p = 0.002 and p = 0.014 for nonlinearity, respectively). When we restricted the analyses to accelerometer-based studies, the third quartile had a 40.36% lower risk of all-cause mortality and a 35.05% lower risk of cardiovascular event than the first quartile (all-cause mortality: Q1 = 4183 steps/day, Q3 = 8959 steps/day; cardiovascular event: Q1 = 3500 steps/day, Q3 = 9500 steps/day; respectively).ConclusionOur meta-analysis suggests inverse associations between higher step count and risk of premature death and cardiovascular events in middle-aged and older adults, with nonlinear dose–response patterns.     

Six high-intensity interval training sessions over 5 days increases maximal oxygen uptake,endurance capacity,and sub-maximal exercise fat oxidation as much as 6 high-intensity interval training sessions over 2 weeks

BackgroundHigh-intensity interval training (HIIT) induces similar or even superior adaptations compared to continuous endurance training. Indeed, just 6 HIIT sessions over 2 weeks significantly improves maximal oxygen uptake (VO_2max), submaximal exercise fat oxidation, and endurance performance. Whether even faster adaptations can be achieved with HIIT is not known. Thus, we aimed to determine whether 2 sessions of HIIT per day, separated by 3 h, every other day for 5 days (double HIIT (HIIT-D), n = 15) could increase VO_2max, submaximal exercise fat oxidation, and endurance capacity as effectively as 6 sessions of HIIT over 2 weeks (single HIIT (HIIT-S), n = 13).MethodsEach training session consisted of 10 × 60 s of cycling at 100% of VO_2max interspersed with 75 s of low-intensity cycling at 60 watt (W). Pre- and post-training assessments included VO_2max, time to exhaustion at ∼80% of VO_2max, and 60-min cycling trials at ∼67% of VO_2max.ResultsSimilar increases (p < 0.05) in VO_2max (HIIT-D: 7.7% vs. HIIT-S: 6.0%, p > 0.05) and endurance capacity (HIIT-D: 80.1% vs. HIIT-S: 79.2%, p > 0.05) were observed. Submaximal exercise carbohydrate oxidation was reduced in the 2 groups after exercise training (HIIT-D: 9.2%, p = 0.014 vs. HIIT-S: 18.8%, p = 0.012) while submaximal exercise fat oxidation was significantly increased in HIIT-D (15.5%, p = 0.048) but not in HIIT-S (9.3%, p = 0.290).ConclusionSix HIIT sessions over 5 days was as effective in increasing VO_2max and endurance capacity and was more effective in improving submaximal exercise fat oxidation than 6 HIIT sessions over 2 weeks.     

Impaired eye tracking is associated with symptom severity but not dynamic postural control in adolescents following concussion

Purpose:The purpose of the study was to(1)examine the relationship between self-reported symptoms and concussion-related eye tracking impairments,and(2)compare gait performance between(a)adolescents with a concussion who have normal eye tracking,(b)adolescents with a concussion who have abnormal eye tracking,and(c)healthy controls.Methods:A total of 30 concussed participants(age:14.4±2.2 years,mean±SD,50%female)and 30 controls(age:14.2±2.2 years,47%female)completed eye tracking and gait assessments.The BOX score is a metric of pupillary disconjugacy,with scores<10 classified as normal and≥10 abnormal.Symptoms were collected using the Post-Concussion Symptom Scale(PCSS),and gait speed was measured with triaxial inertial measurement units.We conducted a linear regression to examine the relationship between PCSS and BOX scores and a two-way mixed effects analysis of variance to examine the effect of group(abnormal BOX,normal BOX,and healthy control)on single-and dual-task gait speed.Results:There was a significant association between total PCSS score and BOX score in the concussion group(β=0.16,p=0.004,95%confidence interval(95%CI):0.06‒0.27),but not in the control group(β=0.21,p=0.08,95%CI:
0.03 to 0.45).There were no significant associations between PCSS symptom profiles and BOX scores in the concussion or control groups.There were also no significant differences in singletask(Abnormal:1.00±0.14 m/s;Normal:1.11§0.21 m/s;Healthy:1.14±0.18 m/s;p=0.08)or dual-task(Abnormal:0.77±0.15 m/s;Normal:0.84±0.21 m/s;Healthy:0.90±0.18 m/s;p=0.16)gait speed.Conclusion:The concussed group with impaired eye tracking reported higher total symptom severity,as well as worse symptom severity across the 5 PCSS symptom domain profiles.However,eye tracking deficits did not appear to be driven by any particular symptom domain.While not statistically significant,the slower gait speeds in those with abnormal BOX scores may still be clinically relevant since gait-related impairments may persist beyond clinical recovery.     

The diagnostic and prognostic utility of the dual-task tandem gait test for pediatric concussion

Background:The tandem gait test has gained interest recently for assessment of concussion recovery.The purpose of our study was to determine the prognostic and diagnostic use of the single-and dual-task tandem gait test,alongside other clinical measures,within 10 days of pediatric concussion.Methods:We assessed 126 patients post-concussion(6.3§2.3 days post-injury,mean§SD)at a pediatric sports medicine clinic and compared them to 58 healthy controls(age:15.6§1.3 years;43%female).We also compared the 31 patients with concussion who developed persistent post-concussion symptoms(PPCS)(age=14.9§2.0 years;48%female)to the 81 patients with concussion who did not develop PPCS following the initial assessment(age:14.1§3.0 years;41%female).All subjects completed a test battery,and concussion patients were monitored until they experienced concussion-symptom resolution.The test battery included tandem gait(single-task,dual-task(performing tandem gait while concurrently completing a cognitive test)conditions),modified Balance Error Scoring System(mBESS),and concussion symptom assessment(Health and Behavior Inventory).We defined PPCS as symptom resolution time>28 days post-concussion for the concussion group.Measurement outcomes included tandem gait time(single-and dual-task),dual-task cognitive accuracy,mBESS errors(single/double/tandem stances),and symptom severity.Results:The concussion group completed the single-task(mean difference=9.1 s,95%confidential interval(95%CI):6.1-12.1)and dual-task(mean difference=12.7 s,95%CI:8.7
16.8)tandem gait test more slowly than the control group.Compared to those who recovered within 28 days of concussion,the PPCS group had slower dual-task tandem gait test times(mean difference=7.9 s,95%CI:2.0-13.9),made more tandem-stance mBESS errors(mean difference=1.3 errors,95%CI:0.2-2.3),and reported more severe symptoms(mean difference=26.6 Health and Behavior Inventory rating,95%CI:21.1-32.6).Conclusion:Worse dual-task tandem gait test time and mBESS tandem stance performance predicted PPCS in pediatric patients evaluated within 10 days of concussion.Tandem gait assessments may provide valuable information augmenting common clinical practices for concussion management.     

Training load characteristics and injury and illness risk identification in elite youth ski racing: A prospective study

PurposeThe study aimed to investigate the role of training load characteristics and injury and illness risk in youth ski racing.MethodsThe training load characteristics as well as traumatic injuries, overuse injuries, and illnesses of 91 elite youth ski racers (age = 12.1 ± 1.3 years, mean ± SD) were prospectively recorded over a period of 1 season by using a sport-specific online database. Multiple linear regression analyses were performed to monitor the influence of training load on injuries and illnesses. Differences in mean training load characteristics between preseason, in-season, and post-season were calculated using multivariate analyses of variance.ResultsDifferences were discovered in the number of weekly training sessions (p = 0.005) between pre-season (4.97 ± 1.57) and post-season (3.24 ± 0.71), in the mean training volume (p = 0.022) between in-season (865.8 ± 197.8 min) and post-season (497.0 ± 225.5 min) and in the mean weekly training intensity (Index) (p = 0.012) between in-season (11.7 ± 1.8) and post-season (8.9 ± 1.7). A total of 185 medical problems were reported (41 traumatic injuries, 12 overuse injuries, and 132 illnesses). The weekly training volume and training intensity was not a significant risk factor for injuries (p > 0.05). Training intensity was found to be a significant risk factor for illnesses in the same week (β = 0.348; p = 0.044; R² = 0.121) and training volume represents a risk factor for illnesses in the following week (β = 0.397; p = 0.027; R² = 0.157).ConclusionA higher training intensity and volume were associated with increased illnesses, but not with a higher risk of injury. Monitoring training and ensuring appropriate progression of training load between weeks may decrease incidents of illness in-season.     

Association between physical activity and digestive-system cancer: An updated systematic review and meta-analysis

BackgroundPhysical activity (PA) may have an impact on digestive-system cancer (DSC) by improving insulin sensitivity and anticancer immune function and by reducing the exposure of the digestive tract to carcinogens by stimulating gastrointestinal motility, thus reducing transit time. The current study aimed to determine the effect of PA on different types of DSC via a systematic review and meta-analysis.MethodsIn accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched for relevant studies in PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure. Using a random effects model, the relationship between PA and different types of DSC was analyzed.ResultsThe data used for meta-analysis were derived from 161 risk estimates in 47 studies involving 5,797,768 participants and 55,162 cases. We assessed the pooled associations between high vs. low PA levels and the risk of DSC (risk ratio (RR)  = 0.82, 95% confidence interval (95%CI): 0.79–0.85), colon cancer (RR = 0.81, 95%CI: 0.76–0.87), rectal cancer (RR = 0.88, 95%CI: 0.80–0.98), colorectal cancer (RR = 0.77, 95%CI: 0.69–0.85), gallbladder cancer (RR = 0.79, 95%CI: 0.64–0.98), gastric cancer (RR = 0.83, 95%CI: 0.76–0.91), liver cancer (RR = 0.73, 0.60–0.89), oropharyngeal cancer (RR = 0.79, 95%CI: 0.72–0.87), and pancreatic cancer (RR = 0.85, 95%CI: 0.78–0.93). The findings were comparable between case-control studies (RR = 0.73, 95%CI: 0.68–0.78) and prospective cohort studies (RR = 0.88, 95%CI: 0.80–0.91). The meta-analysis of 9 studies reporting low, moderate, and high PA levels, with 17 risk estimates, showed that compared to low PA, moderate PA may also reduce the risk of DSC (RR = 0.89, 95%CI: 0.80–1.00), while compared to moderate PA, high PA seemed to slightly increase the risk of DSC, although the results were not statistically significant (RR = 1.11, 95%CI: 0.94–1.32). In addition, limited evidence from 5 studies suggested that meeting the international PA guidelines might not significantly reduce the risk of DSC (RR = 0.96, 95%CI: 0.91–1.02).ConclusionCompared to previous research, this systematic review has provided more comprehensive information about the inverse relationship between PA and DSC risk. The updated evidence from the current meta-analysis indicates that a moderate-to-high PA level is a common protective factor that can significantly lower the overall risk of DSC. However, the reduction rate for specific cancers may vary. In addition, limited evidence suggests that meeting the international PA guidelines might not significantly reduce the risk of DSC. Thus, future studies must be conducted to determine the optimal dosage, frequency, intensity, and duration of PA required to reduce DSC risk effectively.     

Learners’ motivational response to the Science,PE, & Me! curriculum: A situational interest perspective

BackgroundThe Science, PE, & Me! (SPEM) curriculum is a concept-based physical education curriculum that offers students coherent educational experiences for constructing health-related fitness knowledge through movement experiences. The purpose of this study was to evaluate students’ motivational response to the SPEM curriculum from the situational interest perspective.MethodsThe study used a cluster randomized controlled design in which 30 elementary schools in one of the largest metropolitan areas in the eastern United States were randomly assigned to an experimental or comparison condition. Although all students in the 3rd, 4th, and 5th grades in the targeted schools were eligible to participate in the study, a random sample of students from the experimental (n = 1749; 15 schools) and comparison groups (n = 1985; 15 schools) provided data. Students’ motivational response to the SPEM curriculum or comparison curriculum was measured using the previously validated Situational Interest Scale–Elementary. Data were analyzed using structural mean modeling.ResultsThe results demonstrated that the experimental group (as reference group) showed significantly higher enjoyment (z = –2.01), challenge (z = –6.54), exploration (z = –12.195), novelty (z = –8.80), and attention demand (z = –7.90) than the comparison group.ConclusionThe findings indicate that the SPEM curriculum created a more situationally interesting context for learning than the comparison physical education curriculum.     

Meeting 24-h movement guidelines: Prevalence,correlates, and the relationships with overweight and obesity among Chinese children and adolescents

BackgroundMeeting 24-h movement guidelines by children and adolescents has been associated with improved indicators of health, although it has been under-studied in China. Hence, this study aimed to investigate the prevalence of meeting the 24-h movement guidelines, its correlates, and its relationships with body mass index in children and adolescents in China.MethodsCross-sectional data from the 2017 Youth Study in China of 114,072 children and adolescents (mean age = 13.75 years, 49.18% boys) were used. Meeting 24-h movement guidelines (≥60 min of daily moderate-to-vigorous physical activity, ≤2 h of daily leisure screen time, 9–11 h and 8–10 h nightly sleep duration for 6–13-year-olds and 14–17-year-olds, respectively) and height and weight of all participants were assessed. The prevalence of meeting the 24-h movement guidelines and World Health Organization weight status categories were determined. Generalized linear models were used to determine the correlates of meeting the 24-h movement guidelines and the relationships of meeting the 24-h movement guidelines with overweight (OW) and obesity (OB).ResultsOnly 5.12% of Chinese children and adolescents met the 24-h movement guidelines, and 22.44% were classified as OW/OB. Older children and adolescents were less likely to meet the 24-h movement guidelines. Parental education level and family income were positively related to meeting the 24-h movement guidelines. Children and adolescents meeting the 24-h movement guidelines showed lower odds ratios for OW/OB. Compared with participants meeting the 24-h movement guidelines, boys in 4th–6th grades met none of the recommendations (OR = 1.22, 95%CI: 1.06–1.40), met the screen time recommendation only (OR = 1.13, 95%CI: 1.01–1.28), met the nightly sleep duration recommendation only (OR = 1.14, 95%CI: 1.03–1.28), and had significantly higher odds ratios for OW/OB. Similar trends were observed for girls in 4th–6th grades: meeting none of the guidelines (OR = 1.35, 95%CI: 1.14–1.59), meeting sleep duration guidelines only (OR = 1.23, 95%CI: 1.08–1.39), and meeting moderate-to-vigorous physical activity + nightly sleep duration guidelines (OR = 1.24, 95%CI: 1.01–1.54). For girls in 7th–9th grades, the following trend was observed: meeting none of the guidelines (OR = 1.30, 95%CI: 1.01–1.67).ConclusionVery few Chinese children and adolescents met the 24-h movement guidelines. Age (negatively correlated), parental education level, and family income (both positively correlated) were correlates of meeting the 24-h movement guidelines. Children and adolescents meeting the 24-h movement guidelines were more likely to have lower risks for OW/OB, especially in the youngest age group (Grades 4–6); and girls in the middle age group (Grades 7–9) were also more likely to have lower risks for OW/OB. Further research studies should explore additional correlates and determinants for meeting the 24-h movement guidelines. Also, future studies should use longitudinal or interventional designs to determine the relationships between meeting the 24-h movement guidelines and OW/OB and other health indicators, while taking sex and age differences into account.     

Assessment of causal effects of physical activity on neurodegenerative diseases: A Mendelian randomization study

BackgroundPhysical activity has been hypothesized to play a protective role in neurodegenerative diseases. However, effect estimates previously derived from observational studies were prone to confounding or reverse causation.MethodsWe performed a two-sample Mendelian randomization (MR) analysis to explore the causal association of accelerometer-measured physical activity with 3 common neurodegenerative diseases: Alzheimer''s disease (AD), Parkinson''s disease (PD), and amyotrophic lateral sclerosis (ALS). We selected genetic instrumental variants reaching genome-wide significance (p < 5 × 10⁻⁸) from 2 largest meta-analyses of about 91,100 UK Biobank participants. Summary statistics for AD, PD, and ALS were retrieved from the up-to-date studies in European ancestry led by the international consortia. The random-effect, inverse-variance weighted MR was employed as the primary method, while MR pleiotropy residual sum and outlier (MR-PRESSO), weighted median, and MR-Egger were implemented as sensitivity tests. All statistical analyses were performed using the R programming language (Version 3.6.1; R Foundation for Statistical Computing, Vienna, Austria).ResultsPrimary MR analysis and replication analysis utilized 5 and 8 instrumental variables, which explained 0.2% and 0.4% variance in physical activity, respectively. In each set, one variant at 17q21 was significantly associated with PD, and MR sensitivity analyses indicated them it as an outlier and source of heterogeneity and pleiotropy. Primary results with the removal of outlier variants suggested odds ratios (ORs) of neurodegenerative diseases per unit increase in objectively measured physical activity were 1.52 for AD (95% confidence interval (95%CI): 0.88–2.63, p = 0.13) and 3.35 for PD (95%CI: 1.32–8.48, p = 0.01), while inconsistent results were shown in the replication set for AD (OR = 1.06, 95%CI: 1.01–1.12, p = 0.02) and PD (OR = 0.99, 95%CI: 0.88–0.12, p = 0.97). Similarly, the beneficial effect of physical activity on ALS (OR = 0.51, 95%CI: 0.29–0.91, p = 0.02) was not confirmed in the replication analysis (OR = 0.96, 95%CI: 0.91–1.02, p = 0.22).ConclusionGenetically predicted physical activity was not robustly associated with risk of neurodegenerative disorders. Triangulating evidence across other studies is necessary in order to elucidate whether enhancing physical activity is an effective approach in preventing the onset of AD, PD, or ALS.