Abstract

Lifestyle modification has been widely acknowledged as the primary treatment for the metabolic syndrome (MetS). We examined the short-term effects of a non-dieting lifestyle intervention program, within the theoretical psychological framework of self-determination theory (SDT), on metabolic fitness and psychological well-being among premenopausal, clinically obese women. A secondary analysis of a randomized, controlled, 3 month, intensive, community-based lifestyle intervention study was performed on 31 pre-menopausal obese women with the MetS (56.4% of original study sample). These participants had been randomly allocated to a non-dieting lifestyle intervention group (n = 17) or waiting list control (n = 14). Among participants who completed repeat anthropometric and cardiorespiratory fitness measurements after 3 months intervention, the lifestyle intervention group showed a significant improvement in VO2 (mL.kg(-1).min(-1)) compared with control (test for interaction, p = 0.003). No significant difference was found for body mass. Metabolic improvements were evident for diastolic blood pressure and high-density lipoprotein cholesterol in both groups. The lifestyle intervention group also showed significantly improved general psychological well-being compared with the control group (test for interaction, p = 0.0005). All of the psychological well-being subscales showed significant favourable changes in the intervention group as compared with controls. This short-term, non-dieting lifestyle intervention, consistent with the "Health at Every Size" (HAES) obesity treatment paradigm, significantly improved cardiorespiratory fitness and psychological well-being. Metabolic risk tended to improve after 3 months intervention with no significant difference in the resolution of the MetS between intervention and control participants.