Effects of three training types on vitality among older adults: A self-determination theory perspective

ObjectivesTo investigate effects of endurance, functional and strength training on subjective vitality in older adults. Using the self-determination theory (SDT) framework we tested the moderating effects of autonomy support and mediating effects of need satisfaction on participants’ changes in vitality.DesignParallel-groups randomized controlled trial.Methods138 older adults (M = 74.2 years, SD = 4.5) were randomized to a training group or wait-list control, with assessments at baseline, at 7 weeks (short term), and 16 weeks (long term). Mixed models provided estimates of treatment effects, with covariates for moderating effects of autonomy support and mediating effects of need satisfaction (autonomy, competence, relatedness). Inferences were based on uncertainty in standardized effect-sizes (ES) in relation to a smallest important ES of 0.20.ResultsAt short term, effects on vitality were moderate for endurance training (ES = .70, ±.44), and small for functional (ES = .54, ±.36) and strength training (ES = .21, ±.47). At long term only endurance training had a clear effect on vitality (ES = .27, ±.38). Perceived autonomy support moderated the effect of endurance training at short term (ES = .66, ±.66), and functional training at long term (ES = .23, ±.40). Change in competence mediated the effect of functional and strength training at long term, while in endurance training high perceptions of autonomy support moderated the mediation effect of competence on vitality.ConclusionsEndurance training is recommended for increasing subjective vitality in older adults. Moderating effects of autonomy support and mediating effects of need satisfaction are partially consistent with self-determination theory.