High-velocity resistance training improves executive function in mobility-limited older adults.

OBJECTIVES: To examine the effect of high-velocity resistance training (HVRT) on the executive function of middle-aged and older adults with and without mobility limitations. METHODS: Participants (n = 41, female: 48.9%) completed a supervised 12-week HVRT intervention (2 sessions/week; at 40-60% of one-repetition maximum). The sample included 17 middle-aged adults (40-55 years); 16 older adults (>60 years) and 8 mobility-limited older adults (LIM). Executive function was assessed before and after the intervention period and was reported as z-scores. Maximal dynamic strength, peak power, quadriceps muscle thickness, maximal isometric voluntary contraction (MVIC), and functional performance were also measured pre and post intervention. Training-related adaptations in cognitive measures were calculated using a Generalized Estimating Equation model. RESULTS: HVRT improved executive function in LIM (adjusted marginal mean differences [AMMD]: 0.21; 95%CI: 0.04, 0.38; p = 0.040) although no effect on middle-aged (AMMD: 0.04; 95%CI: -0.09; 0.17; p = 0.533) and older (AMMD: -0.11; 95%CI: -0.25; 0.02; p = 0.107) participants was observed. Improvements in maximal dynamic strength, peak power, MVIC, quadriceps muscle thickness, and functional performance were all associated with changes in executive function, and changes in the first four also seem to mediate the association between changes in functional performance and executive function. CONCLUSIONS: HVRT-induced improvement in executive function of mobility-limited older adults were mediated by changes in lower-body muscle strength, power, and muscle thickness. Our findings reinforce the relevance of muscle-strengthening exercises to preserve cognition and mobility in older adults.

Physical Inactivity From Childhood to Adolescence and Incident Depression.

INTRODUCTION: The long-term impact of physical activity during early life on the risk of depression in later stages of adulthood remains unclear. This study examines the association between physical activity during childhood and adolescence and the incidence of depressive symptoms in early, middle, and late adulthood. METHODS: Data from a birth cohort (the 1958 National Child Development Survey), including births (N=17,415) in England, Wales, and Scotland, were used. After birth, 11 more follow-ups were carried out between ages 7 and 62 years (2020). Leisure-time physical activity was assessed through a self-reported questionnaire. Psychological measures were assessed with the teacher-rated Bristol Social Adjustment Guide, the teacher-rated Rutter scale, and the self-rated Malaise Inventory. Leisure-time physical activity and psychological symptoms were examined in all the 11 follow-up assessments included in this study. Best-fit model was used to obtain hazard ratios and 95% CIs of depression symptoms by physical activity status in different ages, including demographic, behavioral, and health-related variables as potential confounders. RESULTS: After multivariate analysis, being physically active at age 16 years reduced the risk of incident elevated depressive symptoms (hazard ratio=0.73, 95% CI=0.62, 0.85) throughout adulthood. The long-term impacts of physical activity practiced at age 16 years persisted throughout adulthood up to age 62 years. CONCLUSIONS: Adolescence is a critical early-life period to promote physical activity for reducing the incidence of elevated depressive symptoms throughout adulthood. Public health policies should promote healthy lifestyles during the lifespan to reduce both the burden of physical inactivity and depressive symptoms at the population level.