Dose-response effects of a Web-based physical activity program on body composition and metabolic health in inactive older adults: additional analyses of a randomized controlled trial.

BACKGROUND: Low physical activity is a major risk factor for several age-related diseases. Recently, we showed in a randomized controlled trial that a 12-week Web-based intervention (Philips DirectLife) to increase physical activity was effective in increasing physical activity levels and metabolic health in an inactive population aged 60-70 years. OBJECTIVE: The goal of this paper was to assess how many participants successfully reached the physical activity level as targeted by the intervention and what the effects of the intervention on body composition and metabolic health in these successful individuals were to provide insight in the maximum attainable effect of the intervention. METHODS: Among the 235 participants in a randomized controlled trial of the Actief en Gezond Oud (AGO) study, we assessed the effects of the intervention on metabolic parameters in those who had successfully reached their personalized physical activity target compared with the entire intervention group. Furthermore, we studied the dose-response effect of increase in physical activity on metabolic outcome within the intervention group. RESULTS: Of the intervention group, 50 of 119 (42.0%) participants successfully reached the physical activity target (corresponding to a 10% increased daily physical activity on average). This group showed markedly higher effects of the intervention compared to the entire intervention group, with greater decreases in body weight (2.74 vs 1.49 kg), waist circumference (3.74 vs 2.33 cm), insulin resistance (HOMA index: 0.23 vs 0.20), and in cholesterol/HDL ratio (0.39 vs 0.20) and Framingham risk score (0.90% vs 0.54%). We found that men compared to women were more likely to be successful. The dose-response analysis showed that there was a significant association between increase in minutes spent in moderate-to-vigorous activity and body weight loss, BMI reduction, waist circumference reduction, HDL cholesterol increasing, and cholesterol/HDL ratio lowering. CONCLUSIONS: Of the intervention group, 42.0% (50/119) reached their daily physical activity end goal, which was associated with a markedly better effect on body composition and metabolic health compared to the effect in the entire intervention group. In this population, men are more likely to be successful in increasing physical activity. Findings demonstrate that improving the effect of such physical activity interventions requires finding new ways to increase the proportion of the population reaching the targeted goal. TRIAL REGISTRATION: Dutch Trial Registry: NTR 3045; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3045 (Archived by WebCite at http://www.webcitation.org/6KPw52dCc).

Being Active, Engaged, and Healthy: Older Persons' Plans and Wishes to Age Successfully.

OBJECTIVES: This study took an emic multidimensional approach on successful aging and examined what older people consider important to age successfully by asking them about their plans and wishes (PWs). Associations between participants' demographics, health status, working life, social contacts, life satisfaction, and their PWs were investigated. METHOD: An online questionnaire was completed by 649 older individuals (55-90 years). Conceptual content analysis was performed to identify important categories in PWs. Quantitative analyses were conducted to examine associations between PWs and participants' characteristics. RESULTS: Most mentioned PWs were related to activities, engagement with life, and health. Seventy-four participants (11.4%) expressed no PWs. Multivariate analysis revealed that having PWs was most strongly related to participants' life satisfaction. Older individuals with a higher life satisfaction indicated significantly more often to have PWs than individuals with a lower life satisfaction. DISCUSSION: The majority of older people desire an active, engaged, and healthy life. PWs were variable and personal, which endorses an emic, multidimensional approach to successful aging. Knowledge on what older individuals find important in their lives and what they want to achieve can assist older individuals in setting and attaining their goals toward aging well.