Purpose:This study aimed to quantify the dose-response association and the minimal effective dose of leisure-time physical activity(PA)to prevent mortality and cardiovascular disease in adults with type 2 diabetes.Met...Purpose:This study aimed to quantify the dose-response association and the minimal effective dose of leisure-time physical activity(PA)to prevent mortality and cardiovascular disease in adults with type 2 diabetes.Methods:Cross-country comparison of 2 prospective cohort studies including 14,913 and 17,457 population-based adults with type 2 diabetes from the UK and China.Baseline leisure-time PA was self-reported and categorized by metabolic equivalent hours per week(MET-h/week)according to World Health Organization recommendations:none,below recommendation(>0-7.49 MET-h/week);at recommended level(7.5-14.9 MET-h/week);above recommendation(>15 MET-h/week).Mortality and cardiovascular disease data were obtained from national registries.Results:During a median follow-up of 12.4 and 9.7 years,in the UK and China cohorts,repectively,higher levels of leisure-time PA were inversely associated with all-cause(1571 and 2351 events)and cardiovascular mortality(392 and 1060 events),mostly consistent with a linear dose-response relationship.PA below,at,and above recommendations,compared with no activity,yielded all-cause mortality hazard ratios of0.94(95%confidence interval(95%CI):0.79-1.12),0.90(95%CI:0.74-1.10),and 0.85(95%CI:0.70-1.02)in British adults and 0.87(95%CI:0.68-1.10),0.88(95%CI:0.74-1.03),and 0.77(95%CI:0.70-0.85)in Chinese adults.Associations with cardiovascular mortality were more pronounced in British adults(0.80(95%CI:0.58-1.11),0.75(95%CI:0.52-1.09),and 0.69(95%CI:0.48-0.97))but less pronounced in Chinese adults(1.06(95%CI:0.76-1.47),1.01(95%CI:0.80-1.28),and 0.79(95%CI:0.69-0.92)).PA at recommended levels was not associated with lower rates of major adverse cardiovascular events(2345 and 4458 events).Conclusion:Leisure-time PA at the recommended levels was not convincingly associated with lower mortality and had no association with risk of major adverse cardiovascular events in British or Chinese adults with type 2 diabetes.Leisure-time PA above current recommendations may be needed to prevent cardiovascular disease and premature mortality in adults with type 2 diabetes.展开更多
Background:Evidence on the health benefits of occupational physical activity(OPA)is inconclusive.We examined the associations of baseline OPA and OPA changes with all-cause,cardiovascular disease(CVD),and cancer morta...Background:Evidence on the health benefits of occupational physical activity(OPA)is inconclusive.We examined the associations of baseline OPA and OPA changes with all-cause,cardiovascular disease(CVD),and cancer mortality and survival times.Methods:This study included prospective and longitudinal data from the MJ Cohort,comprising adults over 18 years recruited in 1998-2016,349,248 adults(177,314 women)with baseline OPA,of whom 105,715(52,503 women)had 2 OPA measures at 6.3±4.2 years(mean±SD)apart.Exposures were baseline OPA,OPA changes,and baseline leisure-time physical activity.Results:Over a mean mortality follow-up of 16.2±5.5 years for men and 16.4±5.4 years for women,11,696 deaths(2033 of CVD and 4631 of cancer causes)in men and 8980 deaths(1475 of CVD and 3689 of cancer causes)in women occurred.Combined moderately heavy/heavy baseline OPA was beneficially associated with all-cause mortality in men(multivariable-adjusted hazard ratio(HR)=0.93,95%confidence interval(95%CI):0.89-0.98 compared to light OPA)and women(HR=0.86,95%CI:0.79-0.93).Over a mean mortality follow-up of 12.5±4.6 years for men and 12.6±4.6 years for women,OPA decreases in men were detrimentally associated(HR=1.16,95%CI:1.01-1.33)with all-cause mortality,while OPA increases in women were beneficially(HR=0.83,95%CI:0.70-0.97)associated with the same outcome.Baseline or changes in OPA showed no associations with CVD or cancer mortality.Conclusion:Higher baseline OPA was beneficially associated with all-cause mortality risk in both men and women.Our longitudinal OPA analyses partly confirmed the prospective findings,with some discordance between sex groups.展开更多
Background:Adopting a healthy lifestyle during childhood could improve physical and mental health outcomes in adulthood and reduce relevant disease burdens.However,the lifestyles of children with mental,behavioral,and...Background:Adopting a healthy lifestyle during childhood could improve physical and mental health outcomes in adulthood and reduce relevant disease burdens.However,the lifestyles of children with mental,behavioral,and developmental disorders(MBDDs)remains under-described within the literature of public health field.This study aimed to examine adherence to 24-hour movement guidelines among children with MBDDs compared to population norms and whether these differences are affected by demographic characteristics.Methods:Data were from the 2016-2020 National Survey of Children’s Health—A national,population-based,cross-sectional study.We used the data of 119,406 children aged 6-17 years,which included 38,571 participants with at least 1 MBDD and 80,835 without.Adherence to the 24-hour movement guidelines was measured using parent-reported physical activity,screen time,and sleep duration.Results:Among children with MBDDs,20.3%,37.0%,60.7%,and 77.3%met the physical activity,screen time,sleep,and at least 1 of the 24-hour movement guidelines.These rates were lower than those in children without MBDDs(22.8%,46.2%,66.7%,and 83.4%,respectively;all p<0.001).Children with MBDDs were less likely to meet these guidelines(odds ratio(OR)=1.21,95%confidence interval(95%CI):1.13-1.30;OR=1.37,95%CI:1.29-1.45;OR=1.29,95%CI:1.21-1.37;OR=1.45,95%CI:1.35-1.56)than children without MBDDs.Children with emotional disorders had the highest odds of not meeting these guidelines(OR=1.43,95%CI:1.29-1.57;OR=1.48,95%CI:1.37-1.60;OR=1.49,95%CI:1.39-1.61;OR=1.72,95%CI:1.57-1.88)in comparison to children with other MBDDs.Among children aged12-17 years,the difference in proportion of meeting physical activity and screen time guidelines for children with vs.children without MBDD was larger than that among children aged 6-11 years.Furthermore,the above difference of meeting physical activity guidelines in ethnic minority children was smaller than that in white children.Conclusion:Children with MBDDs were less likely to meet individual or combined 24-hour movement guidelines than children without MBDDs.In educational and clinical settings,the primary focus should be on increasing physical activity and limiting screen time in children aged 12-17 years who have MBDDs;and specifically for white children who have MBDDs,increasing physical activity may help.展开更多
Sports are a meaningful context in which many young people participate,and youth sports teams may be a viable way to promote optimal development.Sports comprises all forms of physical activities that contribute to phy...Sports are a meaningful context in which many young people participate,and youth sports teams may be a viable way to promote optimal development.Sports comprises all forms of physical activities that contribute to physical fitness,mental well-being and social interaction.Participation in sport improves the development of peer relationships,establishes the notion of trust and builds teamwork skills.The purpose of this study was to see the impact of sports participation on intelligence among boys.The present study was conducted on 300 male subjects between age group 14 and 17 years.Subjects were divided into following three groups(Group 1-Team Sports Group,Group 2-Individual Sports Group,Group 3-Non-participant Group)using a questionnaire for Sports Activity participation survey.Each group has 100 students.To assess intelligence of the selected subjects,verbal intelligence test prepared by Dr.P.Srinivasan was adopted.Appropriate tool was used to assess the parameters.The results show that majority i.e.64.7%of the subjects were found to be average intelligent and 22.7 superiorly intelligent.It was revealed that sports participation has no association withrelation to intelligence(IQ)and revealed that there was no significant effect found on intelligence level of the subjects who participated in sports as well as the non-participants.展开更多
Purpose:This study aimed to examine the reliability and validity of load-velocity(L-V)relationship variables obtained through the 2-point method using different load combinations and velocity variables.Methods:Twenty ...Purpose:This study aimed to examine the reliability and validity of load-velocity(L-V)relationship variables obtained through the 2-point method using different load combinations and velocity variables.Methods:Twenty men performed 2 identical sessions consisting of 2 countermovement jumps against 4 external loads(20 kg,40 kg,60 kg,and80 kg)and a heavy squat against a load linked to a mean velocity(MV)of 0.55 m/s(load_(0.55)).The L-V relationship variables(load-axis intercept(L_(0)),velocity-axis intercept(v_(0)),and area under the L-V relationship line(A_(line)))were obtained using 3 velocity variables(MV,mean propulsive velocity(MPV),and peak velocity)by the multiple-point method including(20-40-60-80-load_(0.55))and excluding(20-40-60-80)the heavy squat,as well as from their respective 2-point methods(20-load_(0.55)and 20-80).Results:The L-V relationship variables were obtained with an acceptable reliability(coefncient of variation(CV)≤7.30%;intra-class correlation coefficient>0.63).The reliability of L_(0)and v_(0)was comparable for both methods(CV_(ratio)(calculated as higher value/lower value):1.11-1.12),but the multiple-point method provided Al_(ine)with a greater reliability(CV_(ratio)=1.26).The use of a heavy squat provided the L-V relationship variables with a comparable or higher reliability than the use of a heavy countermovement jump load(CV_(ratio):1.06-1.19).The peak velocity provided the load-velocity relationship variables with the greatest reliability(CV_(ratio):1.15-1.86)followed by the MV(CV_(ratio):1.07-1.18),and finally the MPV.The 2-point methods only revealed an acceptable validity for the MV and MPV(effect size≤0.19;Pearson s product-moment correlation coefficient≥0.96;Lin's concordance correlation coefficient≥0.94).Conclusion:The 2-point method obtained from a heavy squat load and MV or MPV is a quick,safe,and reliable procedure to evaluate the lower-body maximal neuromuscular capacities through the L-V relationship.展开更多
Neuromuscular activity is suppressed during maximal eccentric(ECC)muscle contraction in untrained subjects owing to attenuated levels of central activation and reduced spinal motor neuron(MN)excitability indicated by ...Neuromuscular activity is suppressed during maximal eccentric(ECC)muscle contraction in untrained subjects owing to attenuated levels of central activation and reduced spinal motor neuron(MN)excitability indicated by reduced electromyography signal amplitude,diminished evoked H-reflex responses,increased autogenic MN inhibition,and decreased excitability in descending corticospinal motor pathways.Maximum ECC muscle force recorded during maximal voluntary contraction can be increased by superimposed electrical muscle stimulation only in untrained individuals and not in trained strength athletes,indicating that the suppression in MN activation is modifiable by resistance training.In support of this notion,maximum ECC muscle strength can be increased by use of heavy-load resistance training owing to a removed or diminished suppression in neuromuscular activity.Prolonged(weeks to months)of heavy-load resistance training results in increased H-reflex and V-wave responses during maximal ECC muscle actions along with marked gains in maximal ECC muscle strength,indicating increased excitability of spinal MNs,decreased presynaptic and/or postsynaptic MN inhibition,and elevated descending motor drive.Notably,the use of supramaximal ECC resistance training can lead to selectively elevated V-wave responses during maximal ECC contraction,demonstrating that adaptive changes in spinal circuitry function and/or gains in descending motor drive can be achieved during maximal ECC contraction in response to heavy-load resistance training.展开更多
Purpose: The present study evaluated the effects of regular participation in small-sided team handball training on body composition, osteogenic response, physical performance, and cardiovascular risk factors, as well ...Purpose: The present study evaluated the effects of regular participation in small-sided team handball training on body composition, osteogenic response, physical performance, and cardiovascular risk factors, as well as well-being and motivation, in young untrained women.Methods: Twenty-eight untrained 20- to 30-year-old women were randomized to a handball training group(HG; n = 14, height 170 ± 5 cm, weight 73 ± 11 kg, VO_(2peak) 37.7 ± 4.1 mL/min/kg) that trained 1.7 ± 0.3 times per week over 12 weeks(70 min 4 v 4 handball sessions) or an inactive control group(CG; n = 14, 169 ± 5 cm, 71 ± 12 kg, 38.1 ± 3.7 mL/min/kg). Physiological and psychological and motivational training adaptations were assessed pre-and post-intervention by dual-energy X-ray Absorptiometry(DXA) scans, blood sampling, physical tests, and questionnaires.Results: The average heart rate(HR) over all training sessions was equal to 85% ± 6% HR_(max). Between-group intervention effects were observed in favor of HG for muscle mass(2.1%, p = 0.024), proximal femur bone mineral density(0.8%, p = 0.041), Yo-Yo IE1 intermittent endurance test level 1(IE1) performance(35%, p < 0.001), and incremental treadmill test performance(11.5%, p = 0.003), but not total fat mass(p = 0.176),mean arterial blood pressure(p = 0.328), resting HR(p = 0.219), or blood lipids(p = 0.298—0.854). In CG, no changes were observed in any of the measured physiological variables after the training period. Compared to CG, HG had an increase in intrinsic motivation(p < 0.001) and in the well-being subscale "energy"(p = 0.010).Conclusion: Participation in regular recreational team handball training organized as small-sided games has marked beneficial effects on physical performance, musculoskeletal fitness, well-being, and motivation in untrained young women.展开更多
Purpose: The aims of this study were to(1) investigate the health-related physical fitness profile of untrained adolescent boys in comparison to adolescent soccer players,(2) determine the intensity and enjoyment of 6...Purpose: The aims of this study were to(1) investigate the health-related physical fitness profile of untrained adolescent boys in comparison to adolescent soccer players,(2) determine the intensity and enjoyment of 6 v 6 and 4 v 4 small-sided games, and(3) evaluate the health-related effects of a short-period of soccer training in the untrained group.Methods: Forty-one adolescent boys(untrained, n = 24: age = 15.9 ± 0.6 years; trained, n = 17: age = 15.7 ± 0.7 years) were recruited. For Purpose 1,the players(n = 17) and the untrained(n = 24) boys were tested for speed, jumping power, postural balance, flexibility, and aerobic capacity. After baseline testing, Purposes 2 and 3 were addressed by randomly assigning the untrained boys to either a soccer-training group(small-sided games,2 sessions per week for 8 weeks) or to a control group, followed by identical retesting.Results: At baseline, physical fitness was higher(p < 0.001) in trained players than in untrained for aerobic fitness, sprinting, jumping power, and postural balance. Small-sided games using 6 v 6 or 4 v 4 elicited similar heart rate(HR)(mean: ~ 85% peak heart rate, HR_(peak)), rate of perceived exertion, and enjoyment responses. Over 8 weeks, the between-group analysis revealed that soccer training had a large beneficial effect on postural balance(45%) when compared with control group with unclear effects on other fitness parameters.Conclusion: Adolescent soccer players had markedly higher physical fitness compared with untrained adolescents. Small-sided soccer games practiced by untrained adolescents elicited high exercise intensity. While 8 weeks of twice-weekly soccer training sessions induced significant improvement in postural balance, the short duration of the study was not sufficient to result in between-group differences in sprint and jump performance or aerobic fitness.展开更多
AIM:To determine the glycemic index(GI)and glycemic load(GL)values of Chinese traditional foods in Hong Kong.METHODS:Fifteen healthy subjects(8 males and 7 females)volunteered to consume either glucose or one of 23 te...AIM:To determine the glycemic index(GI)and glycemic load(GL)values of Chinese traditional foods in Hong Kong.METHODS:Fifteen healthy subjects(8 males and 7 females)volunteered to consume either glucose or one of 23 test foods after 10-14 h overnight fast.The blood glucose concentrations were analyzed immediately before,15,30,45,60,90 and 120 min after food consumption using capillary blood samples.The GI value of each test food was calculated by expressing the incremental area under the blood glucose response curve(IAUC)value for the test food as a percentage of each subject's average IAUC value for the glucose.The GL value of each test food was calculated as the GI value of the food multiplied by the amount of the available carbohydrate in a usual portion size,divided by 100.RESULTS:Among all the 23 Chinese traditional foods tested,6 of them belonged to low GI foods(Tuna Fish Bun,Egg Tart,Green Bean Dessert,Chinese Herbal Jelly,Fried Rice Vermicelli in Singapore-style,and Spring Roll),10 of them belonged to moderate GI foods(Baked Barbecued Pork Puff,Fried Fritter,"Mai-Lai"Cake,"Pineapple"Bun,Fried Rice Noodles with Sliced Beef,Barbecue Pork Bun,Moon Cakes,Glutinous Rice Ball,Instant Sweet Milky Bun,and Salted Meat Rice Dumpling),the others belonged to high GI foods(Fried Rice in Yangzhou-Style,Sticky Rice Wrapped in Lotus Leaf,Steamed Glutinous Rice Roll,Jam and Peanut Butter Toast,Plain Steamed Vermicelli Roll,Red Bean Dessert,and Frozen Sweet Milky Bun).CONCLUSION:The GI and GL values for these Chinese traditional foods will provide some valuable information to both researchers and public on their food preference.展开更多
Purpose: The aim of the present study was to investigate whether street basketball organized as 3 v 3 on either a half court(HC) with 1 basket or a full court(FC) with 2 baskets could improve fitness and health profil...Purpose: The aim of the present study was to investigate whether street basketball organized as 3 v 3 on either a half court(HC) with 1 basket or a full court(FC) with 2 baskets could improve fitness and health profiles of untrained men after 3 months of supervised training.Methods: Thirty-five untrained men(aged 20—42 years) completed the pre-and post-intervention testing(FC: n = 13, HC: n = 12, CO(control):n = 10). The training attendance was 2.0 ± 0.4 and 1.9 ± 0.3 times per week in FC and HC, respectively. Mean heart rate(HR) was 83.8 ± 6.0 percent of maximal heart rate(%HR_(max)) and 84.5 ± 2.9 %HR_(max) in FC and HC, respectively.Results: The 3 months of street basketball training on an FC with 2 baskets increased maximal oxygen uptake(2.4 mL/min/kg(95% confidence interval(CI): 1.0—3.9)), time to exhaustion(47 s(95%CI: 26—67)), lean body mass(0.8 kg(95%CI: 0.1—1.5)), and bone mineral density(0.021 g/cm^2(95%CI: 0.011—0.031)), whereas mean arterial pressure(—5.6 mm Hg(95%CI: —7.5 to 3.7)), body fat percentage(—1.6%,(95%CI: —2.5 to —0.7)), heart rate(—18 bpm(95%CI: —24 to —12)), and blood lactate(median: —1.4 mmol/L(interquartile range: —1.5 to —0.6)) during submaximal running were lowered. The changes were less pronounced after the training period when playing on an HC with 1 basket, but increases in maximal oxygen uptake(1.6 mL/min/kg(95%CI: —0.1 to 3.3)), time to exhaustion(28 s(95%CI: 9—47)), lean body mass(1.3 kg(95%CI: 0.3—2.4)), and lower body fat percentage(—0.9%(95%CI: —1.9 to —0.1)) were observed in this group.Conclusion: Three months of 3 v 3 street basketball training improved fitness and led to broad-spectrum improvements in variables related to overall health profile, with the most marked effects observed when playing on an FC with 2 baskets.展开更多
Objective To assess predictive clinical factors of cardioembolic infarction in very old patients(85 years of age and older).Methods Prospective hospital-based stroke registry("The Sagrat Cor Hospital of Barcelona...Objective To assess predictive clinical factors of cardioembolic infarction in very old patients(85 years of age and older).Methods Prospective hospital-based stroke registry("The Sagrat Cor Hospital of Barcelona Stroke Registry")is an acute-care teaching hospital in Barcelona,Catalonia,Spain.From 956 first-ever cardioembolic stroke patients included in the stroke registry over a 24-year period,639 were younger than 85 years of age and 317 were 85 years or older(mean age:88.9 years).Demographics,clinical characteristics,risk factors and early outcome were compared.Predictors of cardioembolic infarction in the oldest age group were assessed by multivariate analyses.Results In a logistic regression model based on demographics,risk factors,clinical features and complications,female gender(odds ratio[OR]=1.74,95%confidence interval[CI]:1.27–2.39),heart failure(OR=2.27,95%CI:1.46–3.56),altered consciousness(OR=1.76,95%CI:1.28–2.42),and infectious complications(OR=2.01,95%CI:1.39–2.91)were predictors of cardioembolic stroke in the oldest age group.By contrast,heavy smoking,heart valve disease,hypertension,headache,early seizures,sensory deficit,and involvement of the posterior cerebral artery were independently associated with cardioembolic stroke in the younger group.Conclusions Identification of a differential clinical profile of cardioembolic stroke between patients aged 85 years or more and those younger than 85 years helps clinicians to the optimal management of ischemic infarction in the oldest segment of the population.展开更多
BACKGROUND： Some previous studies have shown that exercise is an important factor that affects the latencies of visual-evoked potentials （VEPs）. OBJECTIVE： To investigate the effects of spending a period of time u...BACKGROUND： Some previous studies have shown that exercise is an important factor that affects the latencies of visual-evoked potentials （VEPs）. OBJECTIVE： To investigate the effects of spending a period of time undergoing tennis training on the latencies of VEPs by comparing the latencies of VEPs before tennis training with those after 8 weeks of tennis training. DESIGN, TIME AND SETTING： The non-randomly concurrent controlled experiment was performed in the Department of Human Movement Sciences, Physical Education College, Shandong Normal University from April to June 2007. PARTICIPANTS： In total, 45 healthy volunteers from Shandong Normal University were selected as subjects, including 31 students majoring in physical education （11 males and 5 females participated in the tennis training plan for 8 weeks）, and 14 students from other subjects. Informed consent was obtained. According to whether they were majoring in physical education or not, and whether or not they took part in tennis training, the students were divided into 3 groups： a tennis group of physical education students （n = 16） a non-tennis group of physical education students （n =15） and a non-tennis group of non-physical education students （n = 14）. METHODS： The subjects in the tennis group took part in a regular tennis training plan of 2 hours a day and 3 days per week, for 8 weeks, while the subjects in two non-tennis groups were not in the tennis training plan The NDI-200 neural electricity tester （Shanghai Haishen Medical Electronic Instrument Co., Ltd.） was used to measure VEPs before and after the experiment in all three groups, and to compare the latencies of VEPs recorded before training with those recorded after training. MAIN OUTCOME MEASURES： Comparison of the changes in latencies of VEPs before and after 8 weeks of tennis training. RESULTS： All 45 subjects finished the test and datas from all were included in the statistical analysis. There were no significant differences among all the three groups before tennis training, but the female subjects in each group showed significantly shorter N75 latencies than male subjects of the same group （P 〈 0.05）. Comparing the latencies of VEPs after training with those recorded before training, the N75, P100 and N145 latencies were all found to be significantly shorter than before training in the tennis group （P 〈 0.05）, but the N75, P100 and N145 latencies were unaffected in the two non-tennis groups （P 〉 0.05）; some latencies were even significantly longer than the before-training values. CONCLUSION： Special tennis training for 8 weeks can make the subjects＇ VEP latencies significantly shorter. Thus, VEP latencies can change with tennis training.展开更多
Purpose:The purpose of this study was to determine the effects of 12 weeks of barefoot running on foot strike patterns,inversion-eversion and foot rotation in long-distance runners.Methods:Thirty-one endurance runners...Purpose:The purpose of this study was to determine the effects of 12 weeks of barefoot running on foot strike patterns,inversion-eversion and foot rotation in long-distance runners.Methods:Thirty-one endurance runners with no experience in barefoot running were randomized into a control group and an experimental group who received barefoot training.At pre-test and post-test,all subjects ran at low and high self-selected speeds on a treadmill.Data were collected by systematic observation of lateral and back recordings at 240 Hz.Results:McNemar’s test indicated significant changes(p <0.05) in the experimental group at both high and low speed running in foot strike patterns,reducing the percentage of high rearfoot strikers and increasing the number of midfoot strikers.A significant increase(p <0.05) of external rotation of the foot and a decrease of inversion occurred at comfortable speed in the experimental group.Conclusion:Twelve weeks of barefoot running,applied progressively,causes significant changes in foot strike pattern with a tendency toward midfoot or forefoot strikes,regardless of running speed and significant changes in foot rotation at low speed,while the inversion was reduced in left foot at low speed with a tendency toward centered strike.展开更多
Purpose： The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed （ACLR）, elite （ELITE）, and ado...Purpose： The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed （ACLR）, elite （ELITE）, and adolescent （ADOL） alpine ski racers and ski cross athletes. Methods： Alpine ski racers/ski crossers （ACLR： n = 12, age = 26.7 ± 3.8 years; ELITE： n = 12, age = 23.9 ± 3.0 years; ADOL： n = 12, age = 17.8 ± 0.7 years; females： n = 6 per group, males： n = 6 per group） performed 5 maximal countermovement jumps （CMJs） and 5 squat jumps. The ground reaction forces for each limb were analyzed using dual force plate recording to obtain body center of mass （BCM） velocity, displacement, and power. The eccentric deceleration （ECC） and concentric phases were determined from BCM velocity. CMJ net concentric and ECC impulses were calculated （body mass normalized） along with the peak and mean BCM power and maximal vertical jump height. CMJ lower limb stiffness （LLS） was determined by the slope of the ground reaction forces vs. the BCM displacement curve over the ECC phase. Concentric and ECC asymmetry indices were calculated for each leg, and the left vs. right LLS was compared. Outcome measures （reported as mean ± SD） calculated as a 5-jump mean were normalized to body mass and compared using an analysis of variance. Results： No between-group differences were found for peak and mean power or jump heights. There were no group differences for LLS or net concentric phase impulse, but the net ECC impulse was lower in the ADOL group compared with ELITE skiers （ADOL： 1.33 ± 0.32 Ns/kg; ELITE： 1.59 ± 0.16 Ns/kg; p 〈 0.05）. Although no group differences were found for ECC asymmetry indices, a group × limb interaction was found for LLS （p 〈 0.01）, which was systematically higher in the right vs. the left limb of ADOL skiers （right： 54.1 ± 17.9 N/m/kg; left： 48.7 ± 15.7 N/m/kg;p 〈 0.01）. Conclusion： ADOL skiers demonstrated decreased ECC impulse and systematic right limb dominance in LLS compared with ACLR and ELITE skiers. The implication of these findings for injury and performance are unknown, but further investigation into these potential relationships is warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.展开更多
Remember way back when?When we were kids?We played games like soccer,basketball,rugby,and volleyball because they were fun.If we stayed with it long enough(and became good enough)we might have played competitively,whe...Remember way back when?When we were kids?We played games like soccer,basketball,rugby,and volleyball because they were fun.If we stayed with it long enough(and became good enough)we might have played competitively,where the objective was to win.Herman Edwards,a former head coach in the National Football League(NFL)。展开更多
The Coronavirus disease-2019(COVID-19)pandemic is still spreading globally.As of April 7,2020,it has reached 184 countries and territories,infecting more than 1.4 million people worldwide with more than 82,000 deaths....The Coronavirus disease-2019(COVID-19)pandemic is still spreading globally.As of April 7,2020,it has reached 184 countries and territories,infecting more than 1.4 million people worldwide with more than 82,000 deaths.1 The situation in China has improved significantly since December 31,2019.2 Owing to the unprecedented and effective quarantine measures taken across the country,Chinese health authorities reported on March 18,2020,that for the first time since the outbreak no new locally transmitted COVID-19 cases had been reported,marking a major turning point in the fight against the highly contagious coronavirus.3 Since then,the daily number of new cases in the mainland of China has dropped to double digits,with new infections primarily originating from incoming air passengers from outside China.展开更多
Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the...Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the exercise duration upon these 2 parameters.Methods:Twenty-four semi-professional soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol,either with or without knowledge of the duration of this protocol.Results:A mixed model of analysis of variance showed that kicking maximal ball velocity was significantly affected(F(5,85)=11.6,p<0.001,η^2=0.39) but only after just 1 circuit of the fatigue protocol and then remained similar.Accuracy did not change during the protocol(F(5,75)=0.23,p=0.76,η^2=0.03) and knowing the duration of exercitation did not affect accuracy and velocity development(F(1,23) ≤1.04,p≥0.32,η~2≤0.06).Conclusion:These findings demonstrated the potential negative effects of fatigue on kicking ball velocity in soccer but not in the kicking accuracy and that the effect of fatigue may not be progressive over time.Knowing or not knowing the duration of exercitation did not affect the results.展开更多
The prevalence of pediatric obesity continues to increase worldwide,bringing with it various metabolic,functional,social,and psychological complications.1 Both the prevention and treatment of childhood obesity must be...The prevalence of pediatric obesity continues to increase worldwide,bringing with it various metabolic,functional,social,and psychological complications.1 Both the prevention and treatment of childhood obesity must be based on multidisciplinary approaches combining nutrition,physical activity(PA),and psychological support.2 As an essential element of these multicomponent strategies,regular physical activity has been acknowledged as having beneficial effects on children's and adolescents,body composition,physical fitness,and metabolic profile,as well as on their health-related quality of life,social and psychological health,and academic achievement.3,4 Given that only a relatively small proportion of children and adolescents meet the public health recommendations for PA,5 and given that weight loss exercise-based interventions suffer from a high attrition rate,there is a clear need for appropriate PAs.展开更多
Therapeutic horseback riding(THR)as an animal-assisted intervention is one of the innovative approaches emer-ging in the treatment for children with autism spectrum disorder(ASD).The current study was designed to inve...Therapeutic horseback riding(THR)as an animal-assisted intervention is one of the innovative approaches emer-ging in the treatment for children with autism spectrum disorder(ASD).The current study was designed to inves-tigate the effects of a 12-week,twice a week THR program on motor skills in sixty-eight children with ASD aged 5–10 years old.All participants selected met the DSM-V criteria for ASD,and a total offifty-three participants completed the study.A randomized controlled trial design was utilized for the study.Data was collected via a pre-THR test,interim-THR test,and post-THR test to investigate the possible changes in motor skills throughout the 12-week THR program.Results showed that the THR program significantly improved overall motor skills across time points(p<0.05)and sub-skills of run,gallop and two-hand catch(as compared to the control group,p<0.05).In conclusion,the THR program may be an effective option for improving motor skills in children with ASD and further investigation with a longer period of intervention is warranted.展开更多
Lateral bending of the trunk has been specifically identified as a high risk factor for lower back disorders. However, few studies have presented in vivo kinematic data of the trunk while performing functional lateral...Lateral bending of the trunk has been specifically identified as a high risk factor for lower back disorders. However, few studies have presented in vivo kinematic data of the trunk while performing functional lateral bending tasks. Five healthy male subjects performed lateral lifting and lowering tasks under loading condition ranging from light (2kg) to 100 % of a maximum (ML) at a controlled velocity. Single lowering tasks were also performed at 125% and 150% of ML. Video based movement analysis was used to determine kinematics of the trunk, pelvis, shoulders and neck in the frontal plane. Centre of pressure (COP) data was also obtained from a force platform on which the subjects stood when performing the lifting and lowering tasks. Kinematics of the trunk revealed a smooth and relatively large change in angular displacement (between 69°to 55°) toward the unloaded side during the lifting phase. Trunk angular displacement significantly decreased with increasing lifting load. The trunk was additionally divided into four segments representing the lower and upper lumbar regions and the lower and upper thoracic regions. The greatest displacement in these segments took place at the upper lumbar and lower thoracic regions (ranging from 29°to 22°and 23°to 17°, respectively) with the least displacement occurring in the lower lumbar and upper thoracic regions (approx. 6° and 5°, respectively). Both the upper lumbar and lower thoracic segments showed significant decreases in angular displacement with increasing load. During the single lowering trials the trunk rotated toward the loaded side with slightly less magnitude to that recorded during the lowering phase of the heaviest lifting and lowering conditions. Angular displacements of the upper lumbar and lower thoracic segments also decreased with increasing load in single lowering. Identified changes in the COP displacement were also correlated to increasing lifting and lowering load. The main findings of this study indicate that it is the central sections of the trunk that have the greatest motion展开更多
文摘Purpose:This study aimed to quantify the dose-response association and the minimal effective dose of leisure-time physical activity(PA)to prevent mortality and cardiovascular disease in adults with type 2 diabetes.Methods:Cross-country comparison of 2 prospective cohort studies including 14,913 and 17,457 population-based adults with type 2 diabetes from the UK and China.Baseline leisure-time PA was self-reported and categorized by metabolic equivalent hours per week(MET-h/week)according to World Health Organization recommendations:none,below recommendation(>0-7.49 MET-h/week);at recommended level(7.5-14.9 MET-h/week);above recommendation(>15 MET-h/week).Mortality and cardiovascular disease data were obtained from national registries.Results:During a median follow-up of 12.4 and 9.7 years,in the UK and China cohorts,repectively,higher levels of leisure-time PA were inversely associated with all-cause(1571 and 2351 events)and cardiovascular mortality(392 and 1060 events),mostly consistent with a linear dose-response relationship.PA below,at,and above recommendations,compared with no activity,yielded all-cause mortality hazard ratios of0.94(95%confidence interval(95%CI):0.79-1.12),0.90(95%CI:0.74-1.10),and 0.85(95%CI:0.70-1.02)in British adults and 0.87(95%CI:0.68-1.10),0.88(95%CI:0.74-1.03),and 0.77(95%CI:0.70-0.85)in Chinese adults.Associations with cardiovascular mortality were more pronounced in British adults(0.80(95%CI:0.58-1.11),0.75(95%CI:0.52-1.09),and 0.69(95%CI:0.48-0.97))but less pronounced in Chinese adults(1.06(95%CI:0.76-1.47),1.01(95%CI:0.80-1.28),and 0.79(95%CI:0.69-0.92)).PA at recommended levels was not associated with lower rates of major adverse cardiovascular events(2345 and 4458 events).Conclusion:Leisure-time PA at the recommended levels was not convincingly associated with lower mortality and had no association with risk of major adverse cardiovascular events in British or Chinese adults with type 2 diabetes.Leisure-time PA above current recommendations may be needed to prevent cardiovascular disease and premature mortality in adults with type 2 diabetes.
基金supported by a National Health and Medical Research Council (Australia) Investigator Grant (APP1194510)
文摘Background:Evidence on the health benefits of occupational physical activity(OPA)is inconclusive.We examined the associations of baseline OPA and OPA changes with all-cause,cardiovascular disease(CVD),and cancer mortality and survival times.Methods:This study included prospective and longitudinal data from the MJ Cohort,comprising adults over 18 years recruited in 1998-2016,349,248 adults(177,314 women)with baseline OPA,of whom 105,715(52,503 women)had 2 OPA measures at 6.3±4.2 years(mean±SD)apart.Exposures were baseline OPA,OPA changes,and baseline leisure-time physical activity.Results:Over a mean mortality follow-up of 16.2±5.5 years for men and 16.4±5.4 years for women,11,696 deaths(2033 of CVD and 4631 of cancer causes)in men and 8980 deaths(1475 of CVD and 3689 of cancer causes)in women occurred.Combined moderately heavy/heavy baseline OPA was beneficially associated with all-cause mortality in men(multivariable-adjusted hazard ratio(HR)=0.93,95%confidence interval(95%CI):0.89-0.98 compared to light OPA)and women(HR=0.86,95%CI:0.79-0.93).Over a mean mortality follow-up of 12.5±4.6 years for men and 12.6±4.6 years for women,OPA decreases in men were detrimentally associated(HR=1.16,95%CI:1.01-1.33)with all-cause mortality,while OPA increases in women were beneficially(HR=0.83,95%CI:0.70-0.97)associated with the same outcome.Baseline or changes in OPA showed no associations with CVD or cancer mortality.Conclusion:Higher baseline OPA was beneficially associated with all-cause mortality risk in both men and women.Our longitudinal OPA analyses partly confirmed the prospective findings,with some discordance between sex groups.
基金financial support of the Key-Area Research and Development Program of Guangdong Province(2019B030335001)the National Natural Science Foundation of China(82103794)+2 种基金Guangdong Basic and Applied Basic Research Foundation(2021A1515011757)General Administration of Sport of China and China Institute of Sport Science(19—21)Guangxi Key Research and Development Plan(GUIKEAB18050024)。
文摘Background:Adopting a healthy lifestyle during childhood could improve physical and mental health outcomes in adulthood and reduce relevant disease burdens.However,the lifestyles of children with mental,behavioral,and developmental disorders(MBDDs)remains under-described within the literature of public health field.This study aimed to examine adherence to 24-hour movement guidelines among children with MBDDs compared to population norms and whether these differences are affected by demographic characteristics.Methods:Data were from the 2016-2020 National Survey of Children’s Health—A national,population-based,cross-sectional study.We used the data of 119,406 children aged 6-17 years,which included 38,571 participants with at least 1 MBDD and 80,835 without.Adherence to the 24-hour movement guidelines was measured using parent-reported physical activity,screen time,and sleep duration.Results:Among children with MBDDs,20.3%,37.0%,60.7%,and 77.3%met the physical activity,screen time,sleep,and at least 1 of the 24-hour movement guidelines.These rates were lower than those in children without MBDDs(22.8%,46.2%,66.7%,and 83.4%,respectively;all p<0.001).Children with MBDDs were less likely to meet these guidelines(odds ratio(OR)=1.21,95%confidence interval(95%CI):1.13-1.30;OR=1.37,95%CI:1.29-1.45;OR=1.29,95%CI:1.21-1.37;OR=1.45,95%CI:1.35-1.56)than children without MBDDs.Children with emotional disorders had the highest odds of not meeting these guidelines(OR=1.43,95%CI:1.29-1.57;OR=1.48,95%CI:1.37-1.60;OR=1.49,95%CI:1.39-1.61;OR=1.72,95%CI:1.57-1.88)in comparison to children with other MBDDs.Among children aged12-17 years,the difference in proportion of meeting physical activity and screen time guidelines for children with vs.children without MBDD was larger than that among children aged 6-11 years.Furthermore,the above difference of meeting physical activity guidelines in ethnic minority children was smaller than that in white children.Conclusion:Children with MBDDs were less likely to meet individual or combined 24-hour movement guidelines than children without MBDDs.In educational and clinical settings,the primary focus should be on increasing physical activity and limiting screen time in children aged 12-17 years who have MBDDs;and specifically for white children who have MBDDs,increasing physical activity may help.
文摘Sports are a meaningful context in which many young people participate,and youth sports teams may be a viable way to promote optimal development.Sports comprises all forms of physical activities that contribute to physical fitness,mental well-being and social interaction.Participation in sport improves the development of peer relationships,establishes the notion of trust and builds teamwork skills.The purpose of this study was to see the impact of sports participation on intelligence among boys.The present study was conducted on 300 male subjects between age group 14 and 17 years.Subjects were divided into following three groups(Group 1-Team Sports Group,Group 2-Individual Sports Group,Group 3-Non-participant Group)using a questionnaire for Sports Activity participation survey.Each group has 100 students.To assess intelligence of the selected subjects,verbal intelligence test prepared by Dr.P.Srinivasan was adopted.Appropriate tool was used to assess the parameters.The results show that majority i.e.64.7%of the subjects were found to be average intelligent and 22.7 superiorly intelligent.It was revealed that sports participation has no association withrelation to intelligence(IQ)and revealed that there was no significant effect found on intelligence level of the subjects who participated in sports as well as the non-participants.
文摘Purpose:This study aimed to examine the reliability and validity of load-velocity(L-V)relationship variables obtained through the 2-point method using different load combinations and velocity variables.Methods:Twenty men performed 2 identical sessions consisting of 2 countermovement jumps against 4 external loads(20 kg,40 kg,60 kg,and80 kg)and a heavy squat against a load linked to a mean velocity(MV)of 0.55 m/s(load_(0.55)).The L-V relationship variables(load-axis intercept(L_(0)),velocity-axis intercept(v_(0)),and area under the L-V relationship line(A_(line)))were obtained using 3 velocity variables(MV,mean propulsive velocity(MPV),and peak velocity)by the multiple-point method including(20-40-60-80-load_(0.55))and excluding(20-40-60-80)the heavy squat,as well as from their respective 2-point methods(20-load_(0.55)and 20-80).Results:The L-V relationship variables were obtained with an acceptable reliability(coefncient of variation(CV)≤7.30%;intra-class correlation coefficient>0.63).The reliability of L_(0)and v_(0)was comparable for both methods(CV_(ratio)(calculated as higher value/lower value):1.11-1.12),but the multiple-point method provided Al_(ine)with a greater reliability(CV_(ratio)=1.26).The use of a heavy squat provided the L-V relationship variables with a comparable or higher reliability than the use of a heavy countermovement jump load(CV_(ratio):1.06-1.19).The peak velocity provided the load-velocity relationship variables with the greatest reliability(CV_(ratio):1.15-1.86)followed by the MV(CV_(ratio):1.07-1.18),and finally the MPV.The 2-point methods only revealed an acceptable validity for the MV and MPV(effect size≤0.19;Pearson s product-moment correlation coefficient≥0.96;Lin's concordance correlation coefficient≥0.94).Conclusion:The 2-point method obtained from a heavy squat load and MV or MPV is a quick,safe,and reliable procedure to evaluate the lower-body maximal neuromuscular capacities through the L-V relationship.
文摘Neuromuscular activity is suppressed during maximal eccentric(ECC)muscle contraction in untrained subjects owing to attenuated levels of central activation and reduced spinal motor neuron(MN)excitability indicated by reduced electromyography signal amplitude,diminished evoked H-reflex responses,increased autogenic MN inhibition,and decreased excitability in descending corticospinal motor pathways.Maximum ECC muscle force recorded during maximal voluntary contraction can be increased by superimposed electrical muscle stimulation only in untrained individuals and not in trained strength athletes,indicating that the suppression in MN activation is modifiable by resistance training.In support of this notion,maximum ECC muscle strength can be increased by use of heavy-load resistance training owing to a removed or diminished suppression in neuromuscular activity.Prolonged(weeks to months)of heavy-load resistance training results in increased H-reflex and V-wave responses during maximal ECC muscle actions along with marked gains in maximal ECC muscle strength,indicating increased excitability of spinal MNs,decreased presynaptic and/or postsynaptic MN inhibition,and elevated descending motor drive.Notably,the use of supramaximal ECC resistance training can lead to selectively elevated V-wave responses during maximal ECC contraction,demonstrating that adaptive changes in spinal circuitry function and/or gains in descending motor drive can be achieved during maximal ECC contraction in response to heavy-load resistance training.
基金financial support by TrygFondenNordea-fonden (Nordea-fonden 02-2011-4360)+2 种基金the Danish Handball Federation (Dansk Ha ndbold Forbund, DHF)the European Handball Federation (EHF)funded in part by the Danish and European Handball Federation
文摘Purpose: The present study evaluated the effects of regular participation in small-sided team handball training on body composition, osteogenic response, physical performance, and cardiovascular risk factors, as well as well-being and motivation, in young untrained women.Methods: Twenty-eight untrained 20- to 30-year-old women were randomized to a handball training group(HG; n = 14, height 170 ± 5 cm, weight 73 ± 11 kg, VO_(2peak) 37.7 ± 4.1 mL/min/kg) that trained 1.7 ± 0.3 times per week over 12 weeks(70 min 4 v 4 handball sessions) or an inactive control group(CG; n = 14, 169 ± 5 cm, 71 ± 12 kg, 38.1 ± 3.7 mL/min/kg). Physiological and psychological and motivational training adaptations were assessed pre-and post-intervention by dual-energy X-ray Absorptiometry(DXA) scans, blood sampling, physical tests, and questionnaires.Results: The average heart rate(HR) over all training sessions was equal to 85% ± 6% HR_(max). Between-group intervention effects were observed in favor of HG for muscle mass(2.1%, p = 0.024), proximal femur bone mineral density(0.8%, p = 0.041), Yo-Yo IE1 intermittent endurance test level 1(IE1) performance(35%, p < 0.001), and incremental treadmill test performance(11.5%, p = 0.003), but not total fat mass(p = 0.176),mean arterial blood pressure(p = 0.328), resting HR(p = 0.219), or blood lipids(p = 0.298—0.854). In CG, no changes were observed in any of the measured physiological variables after the training period. Compared to CG, HG had an increase in intrinsic motivation(p < 0.001) and in the well-being subscale "energy"(p = 0.010).Conclusion: Participation in regular recreational team handball training organized as small-sided games has marked beneficial effects on physical performance, musculoskeletal fitness, well-being, and motivation in untrained young women.
文摘Purpose: The aims of this study were to(1) investigate the health-related physical fitness profile of untrained adolescent boys in comparison to adolescent soccer players,(2) determine the intensity and enjoyment of 6 v 6 and 4 v 4 small-sided games, and(3) evaluate the health-related effects of a short-period of soccer training in the untrained group.Methods: Forty-one adolescent boys(untrained, n = 24: age = 15.9 ± 0.6 years; trained, n = 17: age = 15.7 ± 0.7 years) were recruited. For Purpose 1,the players(n = 17) and the untrained(n = 24) boys were tested for speed, jumping power, postural balance, flexibility, and aerobic capacity. After baseline testing, Purposes 2 and 3 were addressed by randomly assigning the untrained boys to either a soccer-training group(small-sided games,2 sessions per week for 8 weeks) or to a control group, followed by identical retesting.Results: At baseline, physical fitness was higher(p < 0.001) in trained players than in untrained for aerobic fitness, sprinting, jumping power, and postural balance. Small-sided games using 6 v 6 or 4 v 4 elicited similar heart rate(HR)(mean: ~ 85% peak heart rate, HR_(peak)), rate of perceived exertion, and enjoyment responses. Over 8 weeks, the between-group analysis revealed that soccer training had a large beneficial effect on postural balance(45%) when compared with control group with unclear effects on other fitness parameters.Conclusion: Adolescent soccer players had markedly higher physical fitness compared with untrained adolescents. Small-sided soccer games practiced by untrained adolescents elicited high exercise intensity. While 8 weeks of twice-weekly soccer training sessions induced significant improvement in postural balance, the short duration of the study was not sufficient to result in between-group differences in sprint and jump performance or aerobic fitness.
基金Supported by General Research Fund from Research Grants Committee of The Government of the Hong Kong SAR,China, No.4440178
文摘AIM:To determine the glycemic index(GI)and glycemic load(GL)values of Chinese traditional foods in Hong Kong.METHODS:Fifteen healthy subjects(8 males and 7 females)volunteered to consume either glucose or one of 23 test foods after 10-14 h overnight fast.The blood glucose concentrations were analyzed immediately before,15,30,45,60,90 and 120 min after food consumption using capillary blood samples.The GI value of each test food was calculated by expressing the incremental area under the blood glucose response curve(IAUC)value for the test food as a percentage of each subject's average IAUC value for the glucose.The GL value of each test food was calculated as the GI value of the food multiplied by the amount of the available carbohydrate in a usual portion size,divided by 100.RESULTS:Among all the 23 Chinese traditional foods tested,6 of them belonged to low GI foods(Tuna Fish Bun,Egg Tart,Green Bean Dessert,Chinese Herbal Jelly,Fried Rice Vermicelli in Singapore-style,and Spring Roll),10 of them belonged to moderate GI foods(Baked Barbecued Pork Puff,Fried Fritter,"Mai-Lai"Cake,"Pineapple"Bun,Fried Rice Noodles with Sliced Beef,Barbecue Pork Bun,Moon Cakes,Glutinous Rice Ball,Instant Sweet Milky Bun,and Salted Meat Rice Dumpling),the others belonged to high GI foods(Fried Rice in Yangzhou-Style,Sticky Rice Wrapped in Lotus Leaf,Steamed Glutinous Rice Roll,Jam and Peanut Butter Toast,Plain Steamed Vermicelli Roll,Red Bean Dessert,and Frozen Sweet Milky Bun).CONCLUSION:The GI and GL values for these Chinese traditional foods will provide some valuable information to both researchers and public on their food preference.
文摘Purpose: The aim of the present study was to investigate whether street basketball organized as 3 v 3 on either a half court(HC) with 1 basket or a full court(FC) with 2 baskets could improve fitness and health profiles of untrained men after 3 months of supervised training.Methods: Thirty-five untrained men(aged 20—42 years) completed the pre-and post-intervention testing(FC: n = 13, HC: n = 12, CO(control):n = 10). The training attendance was 2.0 ± 0.4 and 1.9 ± 0.3 times per week in FC and HC, respectively. Mean heart rate(HR) was 83.8 ± 6.0 percent of maximal heart rate(%HR_(max)) and 84.5 ± 2.9 %HR_(max) in FC and HC, respectively.Results: The 3 months of street basketball training on an FC with 2 baskets increased maximal oxygen uptake(2.4 mL/min/kg(95% confidence interval(CI): 1.0—3.9)), time to exhaustion(47 s(95%CI: 26—67)), lean body mass(0.8 kg(95%CI: 0.1—1.5)), and bone mineral density(0.021 g/cm^2(95%CI: 0.011—0.031)), whereas mean arterial pressure(—5.6 mm Hg(95%CI: —7.5 to 3.7)), body fat percentage(—1.6%,(95%CI: —2.5 to —0.7)), heart rate(—18 bpm(95%CI: —24 to —12)), and blood lactate(median: —1.4 mmol/L(interquartile range: —1.5 to —0.6)) during submaximal running were lowered. The changes were less pronounced after the training period when playing on an HC with 1 basket, but increases in maximal oxygen uptake(1.6 mL/min/kg(95%CI: —0.1 to 3.3)), time to exhaustion(28 s(95%CI: 9—47)), lean body mass(1.3 kg(95%CI: 0.3—2.4)), and lower body fat percentage(—0.9%(95%CI: —1.9 to —0.1)) were observed in this group.Conclusion: Three months of 3 v 3 street basketball training improved fitness and led to broad-spectrum improvements in variables related to overall health profile, with the most marked effects observed when playing on an FC with 2 baskets.
文摘Objective To assess predictive clinical factors of cardioembolic infarction in very old patients(85 years of age and older).Methods Prospective hospital-based stroke registry("The Sagrat Cor Hospital of Barcelona Stroke Registry")is an acute-care teaching hospital in Barcelona,Catalonia,Spain.From 956 first-ever cardioembolic stroke patients included in the stroke registry over a 24-year period,639 were younger than 85 years of age and 317 were 85 years or older(mean age:88.9 years).Demographics,clinical characteristics,risk factors and early outcome were compared.Predictors of cardioembolic infarction in the oldest age group were assessed by multivariate analyses.Results In a logistic regression model based on demographics,risk factors,clinical features and complications,female gender(odds ratio[OR]=1.74,95%confidence interval[CI]:1.27–2.39),heart failure(OR=2.27,95%CI:1.46–3.56),altered consciousness(OR=1.76,95%CI:1.28–2.42),and infectious complications(OR=2.01,95%CI:1.39–2.91)were predictors of cardioembolic stroke in the oldest age group.By contrast,heavy smoking,heart valve disease,hypertension,headache,early seizures,sensory deficit,and involvement of the posterior cerebral artery were independently associated with cardioembolic stroke in the younger group.Conclusions Identification of a differential clinical profile of cardioembolic stroke between patients aged 85 years or more and those younger than 85 years helps clinicians to the optimal management of ischemic infarction in the oldest segment of the population.
文摘BACKGROUND： Some previous studies have shown that exercise is an important factor that affects the latencies of visual-evoked potentials （VEPs）. OBJECTIVE： To investigate the effects of spending a period of time undergoing tennis training on the latencies of VEPs by comparing the latencies of VEPs before tennis training with those after 8 weeks of tennis training. DESIGN, TIME AND SETTING： The non-randomly concurrent controlled experiment was performed in the Department of Human Movement Sciences, Physical Education College, Shandong Normal University from April to June 2007. PARTICIPANTS： In total, 45 healthy volunteers from Shandong Normal University were selected as subjects, including 31 students majoring in physical education （11 males and 5 females participated in the tennis training plan for 8 weeks）, and 14 students from other subjects. Informed consent was obtained. According to whether they were majoring in physical education or not, and whether or not they took part in tennis training, the students were divided into 3 groups： a tennis group of physical education students （n = 16） a non-tennis group of physical education students （n =15） and a non-tennis group of non-physical education students （n = 14）. METHODS： The subjects in the tennis group took part in a regular tennis training plan of 2 hours a day and 3 days per week, for 8 weeks, while the subjects in two non-tennis groups were not in the tennis training plan The NDI-200 neural electricity tester （Shanghai Haishen Medical Electronic Instrument Co., Ltd.） was used to measure VEPs before and after the experiment in all three groups, and to compare the latencies of VEPs recorded before training with those recorded after training. MAIN OUTCOME MEASURES： Comparison of the changes in latencies of VEPs before and after 8 weeks of tennis training. RESULTS： All 45 subjects finished the test and datas from all were included in the statistical analysis. There were no significant differences among all the three groups before tennis training, but the female subjects in each group showed significantly shorter N75 latencies than male subjects of the same group （P 〈 0.05）. Comparing the latencies of VEPs after training with those recorded before training, the N75, P100 and N145 latencies were all found to be significantly shorter than before training in the tennis group （P 〈 0.05）, but the N75, P100 and N145 latencies were unaffected in the two non-tennis groups （P 〉 0.05）; some latencies were even significantly longer than the before-training values. CONCLUSION： Special tennis training for 8 weeks can make the subjects＇ VEP latencies significantly shorter. Thus, VEP latencies can change with tennis training.
文摘Purpose:The purpose of this study was to determine the effects of 12 weeks of barefoot running on foot strike patterns,inversion-eversion and foot rotation in long-distance runners.Methods:Thirty-one endurance runners with no experience in barefoot running were randomized into a control group and an experimental group who received barefoot training.At pre-test and post-test,all subjects ran at low and high self-selected speeds on a treadmill.Data were collected by systematic observation of lateral and back recordings at 240 Hz.Results:McNemar’s test indicated significant changes(p <0.05) in the experimental group at both high and low speed running in foot strike patterns,reducing the percentage of high rearfoot strikers and increasing the number of midfoot strikers.A significant increase(p <0.05) of external rotation of the foot and a decrease of inversion occurred at comfortable speed in the experimental group.Conclusion:Twelve weeks of barefoot running,applied progressively,causes significant changes in foot strike pattern with a tendency toward midfoot or forefoot strikes,regardless of running speed and significant changes in foot rotation at low speed,while the inversion was reduced in left foot at low speed with a tendency toward centered strike.
基金the Killam Foundation provided funding for this research
文摘Purpose： The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed （ACLR）, elite （ELITE）, and adolescent （ADOL） alpine ski racers and ski cross athletes. Methods： Alpine ski racers/ski crossers （ACLR： n = 12, age = 26.7 ± 3.8 years; ELITE： n = 12, age = 23.9 ± 3.0 years; ADOL： n = 12, age = 17.8 ± 0.7 years; females： n = 6 per group, males： n = 6 per group） performed 5 maximal countermovement jumps （CMJs） and 5 squat jumps. The ground reaction forces for each limb were analyzed using dual force plate recording to obtain body center of mass （BCM） velocity, displacement, and power. The eccentric deceleration （ECC） and concentric phases were determined from BCM velocity. CMJ net concentric and ECC impulses were calculated （body mass normalized） along with the peak and mean BCM power and maximal vertical jump height. CMJ lower limb stiffness （LLS） was determined by the slope of the ground reaction forces vs. the BCM displacement curve over the ECC phase. Concentric and ECC asymmetry indices were calculated for each leg, and the left vs. right LLS was compared. Outcome measures （reported as mean ± SD） calculated as a 5-jump mean were normalized to body mass and compared using an analysis of variance. Results： No between-group differences were found for peak and mean power or jump heights. There were no group differences for LLS or net concentric phase impulse, but the net ECC impulse was lower in the ADOL group compared with ELITE skiers （ADOL： 1.33 ± 0.32 Ns/kg; ELITE： 1.59 ± 0.16 Ns/kg; p 〈 0.05）. Although no group differences were found for ECC asymmetry indices, a group × limb interaction was found for LLS （p 〈 0.01）, which was systematically higher in the right vs. the left limb of ADOL skiers （right： 54.1 ± 17.9 N/m/kg; left： 48.7 ± 15.7 N/m/kg;p 〈 0.01）. Conclusion： ADOL skiers demonstrated decreased ECC impulse and systematic right limb dominance in LLS compared with ACLR and ELITE skiers. The implication of these findings for injury and performance are unknown, but further investigation into these potential relationships is warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.
文摘Remember way back when?When we were kids?We played games like soccer,basketball,rugby,and volleyball because they were fun.If we stayed with it long enough(and became good enough)we might have played competitively,where the objective was to win.Herman Edwards,a former head coach in the National Football League(NFL)。
文摘The Coronavirus disease-2019(COVID-19)pandemic is still spreading globally.As of April 7,2020,it has reached 184 countries and territories,infecting more than 1.4 million people worldwide with more than 82,000 deaths.1 The situation in China has improved significantly since December 31,2019.2 Owing to the unprecedented and effective quarantine measures taken across the country,Chinese health authorities reported on March 18,2020,that for the first time since the outbreak no new locally transmitted COVID-19 cases had been reported,marking a major turning point in the fight against the highly contagious coronavirus.3 Since then,the daily number of new cases in the mainland of China has dropped to double digits,with new infections primarily originating from incoming air passengers from outside China.
基金supported by the National Funds through FCT,Portuguese Foundation for Science and Technology (UID/DTP/04045/2013)the European Fund for regional development (FEDER) allocated by European Union through the COMPETE 2020 Programme (POCI-01-0145-FEDER006969),Competitiveness and internationalization (POCI)
文摘Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the exercise duration upon these 2 parameters.Methods:Twenty-four semi-professional soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol,either with or without knowledge of the duration of this protocol.Results:A mixed model of analysis of variance showed that kicking maximal ball velocity was significantly affected(F(5,85)=11.6,p<0.001,η^2=0.39) but only after just 1 circuit of the fatigue protocol and then remained similar.Accuracy did not change during the protocol(F(5,75)=0.23,p=0.76,η^2=0.03) and knowing the duration of exercitation did not affect accuracy and velocity development(F(1,23) ≤1.04,p≥0.32,η~2≤0.06).Conclusion:These findings demonstrated the potential negative effects of fatigue on kicking ball velocity in soccer but not in the kicking accuracy and that the effect of fatigue may not be progressive over time.Knowing or not knowing the duration of exercitation did not affect the results.
文摘The prevalence of pediatric obesity continues to increase worldwide,bringing with it various metabolic,functional,social,and psychological complications.1 Both the prevention and treatment of childhood obesity must be based on multidisciplinary approaches combining nutrition,physical activity(PA),and psychological support.2 As an essential element of these multicomponent strategies,regular physical activity has been acknowledged as having beneficial effects on children's and adolescents,body composition,physical fitness,and metabolic profile,as well as on their health-related quality of life,social and psychological health,and academic achievement.3,4 Given that only a relatively small proportion of children and adolescents meet the public health recommendations for PA,5 and given that weight loss exercise-based interventions suffer from a high attrition rate,there is a clear need for appropriate PAs.
基金funded by Guangdong Planning Office of Philosophy and Social Science(General Project in 2021,No.GD21CTY02)Shenzhen University Young Teachers Research Initiation Project(No.20210402)+1 种基金This study is supported by Start-Up Research Grant of Shenzhen University(20200807163056003)Start-Up Research Grant(Peacock Plan:20191105534C).
文摘Therapeutic horseback riding(THR)as an animal-assisted intervention is one of the innovative approaches emer-ging in the treatment for children with autism spectrum disorder(ASD).The current study was designed to inves-tigate the effects of a 12-week,twice a week THR program on motor skills in sixty-eight children with ASD aged 5–10 years old.All participants selected met the DSM-V criteria for ASD,and a total offifty-three participants completed the study.A randomized controlled trial design was utilized for the study.Data was collected via a pre-THR test,interim-THR test,and post-THR test to investigate the possible changes in motor skills throughout the 12-week THR program.Results showed that the THR program significantly improved overall motor skills across time points(p<0.05)and sub-skills of run,gallop and two-hand catch(as compared to the control group,p<0.05).In conclusion,the THR program may be an effective option for improving motor skills in children with ASD and further investigation with a longer period of intervention is warranted.
文摘Lateral bending of the trunk has been specifically identified as a high risk factor for lower back disorders. However, few studies have presented in vivo kinematic data of the trunk while performing functional lateral bending tasks. Five healthy male subjects performed lateral lifting and lowering tasks under loading condition ranging from light (2kg) to 100 % of a maximum (ML) at a controlled velocity. Single lowering tasks were also performed at 125% and 150% of ML. Video based movement analysis was used to determine kinematics of the trunk, pelvis, shoulders and neck in the frontal plane. Centre of pressure (COP) data was also obtained from a force platform on which the subjects stood when performing the lifting and lowering tasks. Kinematics of the trunk revealed a smooth and relatively large change in angular displacement (between 69°to 55°) toward the unloaded side during the lifting phase. Trunk angular displacement significantly decreased with increasing lifting load. The trunk was additionally divided into four segments representing the lower and upper lumbar regions and the lower and upper thoracic regions. The greatest displacement in these segments took place at the upper lumbar and lower thoracic regions (ranging from 29°to 22°and 23°to 17°, respectively) with the least displacement occurring in the lower lumbar and upper thoracic regions (approx. 6° and 5°, respectively). Both the upper lumbar and lower thoracic segments showed significant decreases in angular displacement with increasing load. During the single lowering trials the trunk rotated toward the loaded side with slightly less magnitude to that recorded during the lowering phase of the heaviest lifting and lowering conditions. Angular displacements of the upper lumbar and lower thoracic segments also decreased with increasing load in single lowering. Identified changes in the COP displacement were also correlated to increasing lifting and lowering load. The main findings of this study indicate that it is the central sections of the trunk that have the greatest motion
