ECSS Paris 2023: CP-MH05
INTRODUCTION: Adolescent obesity is associated with early cardiometabolic risk and impaired physical fitness. High-intensity interval-based exercise is time-efficient and potentially scalable in school settings; however, the minimal effective weekly frequency of non-running, low-equipment high-intensity training (HIT) remains unclear. Direct head-to-head comparisons of different weekly frequencies within controlled school-based programs are limited. This pilot randomized trial examined dose-response patterns across weekly HIT frequencies in adolescents with obesity. METHODS: Thirty-one Chinese adolescents with obesity (11–13 years) were randomly allocated to low (1 session/week; n=10), moderate (2 sessions/week; n=10), or high (3 sessions/week; n=11) frequency school-based HIT for 12 weeks. Sessions were delivered within regular physical education classes and comprised three circuits of six bodyweight exercises (30 s work, 30 s recovery per station), targeting 80–90% age-predicted HRmax. Primary outcomes were BMI z-score and waist circumference. Secondary outcomes included fat mass, fat-free mass, bone mineral density (BMD), fasting glucose and lipid profile, directly measured VO2max (COSMED K5), blood pressure, and handgrip strength. Linear mixed models and ANCOVA on change scores were applied. RESULTS: All 31 participants (24 boys; mean age 12.8 ± 0.4 years) completed the intervention with >90% attendance and no exercise-related adverse events. Improvements in adiposity outcomes showed a graded pattern from low to high frequency, including reductions in body weight (-1.05, -2.14, -4.02 kg), BMI (-0.54, -1.26, -2.33 kg/m2), and BMI z-score (-0.10, -0.25, -0.52). Relative handgrip strength increased more markedly at higher weekly frequencies. Directly measured VO2max improved in all groups, with numerically greater gains at higher frequencies. Diastolic blood pressure showed a favorable trend with increasing weekly dose. BMD increased over time (0.06–0.08 g/cm2; time effect p=0.001) with similar gains across frequencies. Metabolic markers (HOMA-IR and triglycerides) improved modestly. CONCLUSION: A brief, school-feasible, non-running HIT program performed 1–3 times per week appears safe and beneficial for adolescents with obesity. Once-weekly HIT may yield meaningful improvements in adiposity and fitness, while higher weekly frequencies may provide additional benefits in central adiposity and aerobic capacity. These findings support flexible frequency prescriptions within constrained physical education time.
Read CV Yuhang GaoECSS Paris 2023: CP-MH05
INTRODUCTION: Obesity is a major risk factor for cardiovascular diseases and various chronic diseases Previous research has demonstrated that physical activity during youth plays a significant role in maintaining health including psychological and cardiovascular functions into adulthood. However, there is currently a lack of systematic evidence regarding how participation in university sports clubs with varying cardiovascular intensity affects the risk of developing obesity decades after graduation, particularly during middle and older age. This university period represents a critical transition from student life to professional careers. Further investigation is needed into how the specific organizational structures of sports clubs and their respective exercise intensities contribute to the long-term suppression of Body Mass Index (BMI) increases. This study examined the relationship between participation in different sport disciplines during university and the risk of obesity in middle and older age among male graduates of a faculty of sports. METHODS: This study included 2,148 graduates of a faculty of sports (graduating between 1969 and 2018). Data were collected through a self-administered, mail in questionnaire. Obesity risk was defined as a BMI ≥25 kg/m2 (overweight and obesity) according to the WHO criteria. University clubs were classified into three groups of cardiovascular intensity (low, moderate, high), following the classification system of sport disciplines by the American College of Cardiology. This classification considers the static and dynamic components of an activity, which correspond to the estimated percent of maximal voluntary contraction reached and maximal oxygen uptake achieved, respectively. Statistical analysis was performed using the Cox proportional hazards model to examine the association between sports club intensity and obesity risk, adjusted for university-era BMI, age at the time of the survey, MVPA, smoking status, and alcohol consumption. RESULTS: The study participants were middle-aged and older men, with a mean follow up period of 33.1±7.6 years. After data screening, 778 individuals with university-era sports club experience were included in the analysis (mean age: 55.1±7.7 years; 666 middle-aged [85.6%] and 112 older participants [14.4%]). Among all respondents, 250 (32.1%) were categorized as overweight or obese. Adjusted hazard ratios and 95% confidence intervals associated with the low, moderate, and high cardiovascular intensity sports were 1.00 (reference), 0.62(0.43 to 0.88, P=0.007) and 0.71(0.46 to 1.09, P=0.120) in middle-aged man, respectively. CONCLUSION: Participation in university sports clubs with moderate cardiovascular intensity was shown to significantly reduce the risk of obesity during middle age, even several decades after graduation. These findings suggest that the intensity of physical activity during the transition from youth to adulthood may have long-lasting protective effects against obesity in later life.
Read CV DONGHAI XUECSS Paris 2023: CP-MH05