Effect of aerobic exercise on insulin resistance and centra1 adiposity disappeared after the discontinuation of intervention in overweight women

Purpose： This study aimed to assess whether the benefits of exercise on central adiposity and insulin resistance （HOMA-IR） are maintained after discontinuation of intervention in the overweight/obese （OWOB） women. Methods： The study subjects were from 2 independent studies with similar aerobic exercise （AE） intervention programs. In study I, I50WOB postmenopausal women with pre-diabetes （body mass index, BMI = 24-33 kg/m2, aged 52-65 years） completed an 8-month exercise intervention and were followed for 2 years after the intervention. In study lI, 12 OWOB （BM1 = 25-35 kg/m2, aged 30-50 years） premenopausal women participated in a 6-week AE and were followed for 4 years after the intervention. The exercise program consisted of progressive AE with intensity of 60%-75% of initial fitness level, 30-60 min/time and 3-5 times/week. Fat mass （FM） was assessed by Dual Energy X-ray Absorptiometry （DXA Prodigy; study I） or bioelectrical impedance device （Inbody 720; study II）. Plasma glucose and insulin were assessed by chemiluminescent immunoassay and HOMA-IR was calculated. Results： Both 8-month and 6-week moderate AE were effective in reducing HOMA-IR （-18.9%, p = 0.012 and -26.7%, p = 0.046, respectively）, and 8-month AE reduced FM at upper abdominal region （-6.2%, p = 0.021）. However, these improvements were not maintained in either study at the follow-up. Conclusion： The AE program used in these studies was effective to reduce insulin resistance and/or FM in central body region among overweight and obese women. However, when exercise intervention was discontinued, the beneficial effects following both short- and long-term intervention disappeared. Thus maintaining exercise seems to be required if one wants to reap the benefits of exercise in the long-term.

Specific Types of Screen-Based Sedentary Time and Depressive Symptoms in Adolescents

Purpose:Screen-based sedentary behavior(SSB)has been identified as risk factor for mental disorders in most of adolescents.However,there is little literature pertaining to the specific kinds of SSB and its connections with depressive symptoms in most of adolescents.In the present study,we are going tofind out the connections between specific types of SSB and depressive symptoms in Chinese adolescents.Methods:A cross-sectional data based on 996 study participants of middle school students in Guangdong Province.SSB was evaluated by distri-buting the questionnaire of Health Behavior in School-aged Children,while depressive symptoms were evaluated using Chinese version of Children’s Depressive symptoms Inventory(CDI).SSB was categorized into TV/movie time,video games time and other electronic devices-based time(e.g.,mobile phone,computer use).Generalized linear models was used to explore the connections between specific kinds of SSB and depressive symptoms.Results:After controlling for variables of sex,ethnicity,grade,residence,siblings,perceived family affluence,father educational level,mother educational background,body mass index(BMI),physical exercise,duration of sleep,other electronic devices-based time was positively correlated with depressive symptoms in Chinese adolescents(B=0.557%,95%CI:0.187–0.926,p=0.003).This significant connection was also found in girls(B=0.728%,95%CI:0.230–1.225,p=0.004)instead of boys(p>0.05).The other types of SSB were not signifi-cantly in relation to depressive symptoms in adolescents regardless of sex.Conclusion:This study suggested that it might be effective in reducing or preventing depressive symptoms through limiting electronic devices-based time,like computer use or mobile phone use time.This strategy would be particularly useful in girls.Future stu-dies should negate or replicate the research results by introducing more improved study design,which is beneficial to better understand the connections between SSB and depressive symptoms as well as then design more efficient interventions in adolescents.

Physical activity continuum throughout the lifespan:Is exercise medicine or what?

In 2007, the American Medical Association and the Ameri- can College of Sports Medicine co-launched a health initiative called ＂Exercise is Medicine＂. It soon became a multinational collaboration, currently involving 43 national centers across the globe.1 Moreover, the slogan ＂Exercise is Medicine＂ has quickly spread outside healthcare settings and has become a popular discourse surrounding exercise. In recent years, however, some exercise scientists began to question if the medical model of exercise makes it an attractive approach for promoting exercise. In this special issue of Journal of Sport and Health Science, we present the views of leading researchers in exercise sociology, sport and exercise psychology, exercise physiology, as well as sports and exercise medicine who par- ticipated in an international symposium on Physical activity continuum throughout the lifespan： Is exercise a medicine or what？. This symposium was organized by the Shanghai Jiao Tong University and the China Sport Science Society in Shanghai on November 11-12, 2015.

Effects of Gua Sha therapy on weightlifting training: a randomized trial

OBJECTIVE: To evaluate the effect of Gua Sha therapy on weightlifting training.METHODS: The sample size was calculated by conducting a pilot study. A total of 44 male weightlifters were randomly assigned to either the Gua Sha group(n = 15), sham scraping group(n = 14), or control group(n = 14). The participants in the Gua Sha group and sham scraping group received 16 sessions of Gua Sha therapy during normal weightlifting training for 8 weeks. No treatment was applied to participants in the control group. The effectiveness of Gua Sha therapy was evaluated by measuring weightlifting ability, the rating of perceived exertion(RPE) of snatch and clean and jerk(85% of1 repetition maximum), and creatinine kinase(CK),blood urea nitrogen(BUN), and immunoglobulin A levels.RESULTS: Gua Sha therapy treatment significantly increased weightlifting ability in participants in the Gua Sha group(P < 0.01). The RPE values of snatch and clean and jerk were significantly lower in the Gua Sha group and sham scraping groups compared with the control group(P < 0.05). CK levels were lower and immunoglobulin A levels were significantly higher in the Gua Sha group compared with sham scraping group and control group(both P < 0.05). BUN levels tended to be reduced only in the Gua Sha group. A close correlation between CK levels and the RPE was found in the Gua Sha group.CONCLUSION: Gua Sha therapy can facilitate weightlifting ability, reduce the RPE, and inhibit muscle injury by promoting recovery from fatigue caused by normal weightlifting training. Gua Sha therapy could be an effective treatment to complement normal weightlifting training.

Move More,Sit Less and Sleep Well:An analysis of WHO movement guidelines for children under 5 years of age

Insufficient physical activity(PA),prolonged sedentary behavior(SB)and inadequate sleep(SLP)are detrimental factors to population health.To address health issues caused by insufficient PA,excessive SB and poor SLP,the World Health Organization(WHO)updated PA and SB guidelines for all populations aged from 5 years to 65 years and older in 2020.For children under 5 years old,the WHO issued the first global guidelines for PA,SB and SLP(collectively refer to movement behaviors)in April 2019.The guidelines applied a holistic approach to promote health behaviors,filling the gap of no comprehensive global movement guidelines for young children.Although the guidelines for young children offer guidance for health promotion,some research and practice implications and other issues should be mentioned.This commentary includes considerations for the importance of the WHO guidelines for younger children,critical analysis of evidence for developing the guidelines,and recommendations for future research and practice.The aim of this paper is to further advance health research in younger populations.