Does personality moderate the efficacy of physical and cognitive training interventions? A 12-month randomized controlled trial in older adults

This study investigated whether personality traits moderate the effects of a 12-month physical or combined physical and cognitive training interventions on physical and cognitive functioning. Participants were community-dwelling 70–85-year-old adults (n = 314). They were randomly assigned to physical training (weekly supervised walking/balance and strength/balance training, home exercises 2–3×/wk and moderate aerobic activity) or to a physical and cognitive training group (the same physical training and computer training on executive functions 3–4×/wk). The outcomes assessed at baseline and post-intervention were physical (maximum gait speed, six-minute walking distance, dual-task cost on gait speed) and cognitive functioning (Stroop, Trail-Making Test-B, verbal fluency, CERAD total score). Personality traits (NEO-PI-3, n = 239) were assessed post-intervention. Personality traits did not moderate intervention effects on physical functioning. Higher openness was associated with greater improvement in CERAD scores, especially in the physical and cognitive training group (group×time×trait B = -0.08, p = .038). Lower neuroticism (time×trait B = -0.04, p = .021) and higher conscientiousness (time×trait B = 0.04, p = .027) were associated with greater improvement in CERAD scores in both groups. Personality traits had mostly null moderating effects across physical and cognitive outcomes, with the possible exception of CERAD score. Individuals with more adaptive personality traits gained more on global cognitive scores during a 12-month training intervention.