Impacts of Adolescent and Young Adult Civic Engagement on Health and Socioeconomic Status in Adulthood

The present study examines links between civic engagement (voting, volunteering, and activism) during late adolescence and early adulthood, and socioeconomic status and mental and physical health in adulthood. Using nationally representative data from the National Longitudinal Study of Adolescent to Adult Health, a propensity score matching approach is used to rigorously estimate how civic engagement is associated with outcomes among 9,471 adolescents and young adults (baseline M_age = 15.9). All forms of civic engagement are positively associated with subsequent income and education level. Volunteering and voting are favorably associated with subsequent mental health and health behaviors, and activism is associated with more health-risk behaviors and not associated with mental health. Civic engagement is not associated with physical health.     

Optimized versus corrected peak power during friction-braked cycle ergometry in males and females

The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 +/- 122 and 668 +/- 37 W) was lower (P < 0.01) than either the highest (1074 +/- 111 and 754 +/- 56 W respectively) or the mean (1007 +/- 125 and 701 +/- 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 +/- 30 W in males and 33 +/- 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.     

Short-term heat acclimation prior to a multi-day desert ultra-marathon improves physiological and psychological responses without compromising immune status

Multistage, ultra-endurance events in hot, humid conditions necessitate thermal adaptation, often achieved through short term heat acclimation (STHA), to improve performance by reducing thermoregulatory strain and perceptions of heat stress. This study investigated the physiological, perceptual and immunological responses to STHA prior to the Marathon des Sables. Eight athletes (age 42 ± 4 years and body mass 81.9 ± 15.0 kg) completed 4 days of controlled hyperthermia STHA (60 min·day^?1, 45°C and 30% relative humidity). Pre, during and post sessions, physiological and perceptual measures were recorded. Immunological measures were recorded pre-post sessions 1 and 4. STHA improved thermal comfort (P = 0.02), sensation (P = 0.03) and perceived exertion (P = 0.04). A dissociated relationship between perceptual fatigue and T_re was evident after STHA, with reductions in perceived Physical (P = 0.04) and General (P = 0.04) fatigue. Exercising T_re and HR did not change (P > 0.05) however, sweat rate increased 14% (P = 0.02). No changes were found in white blood cell counts or content (P > 0.05). Four days of STHA facilitates effective perceptual adaptations, without compromising immune status prior to an ultra-endurance race in heat stress. A greater physiological strain is required to confer optimal physiological adaptations.