Impact of motivational interviewing as a follow-up to an exercise intervention among women with or at risk for metabolic syndrome: A randomized controlled trial

Objectives: Women have a higher prevalence of metabolic syndrome than their male counterparts, and interventions should target women with or at risk for metabolic syndrome. The objective of this study was to compare two intervention strategies on long-term outcomes following the completion of an exercise intervention. Methods: Twenty-six women (M age = 43.35 +/- 9.03) with at least one risk factor for metabolic syndrome were randomized into either a motivational interviewing group (n = 10) or self-regulation-based mobile messaging control group (n = 16) as a 12-week follow-up to a 10-week, 30-session exercise intervention. Outcomes of interest were body fat percentage, bone mineral density, waist circumference, systolic blood pressure, diastolic blood pressure, triglycerides, high-density cholesterol, and fasting blood glucose. Results: Mixed ANOVAs revealed a significant effect for group x time for body fat percentage F(1, 24) = 8.30, p = 0.01, eta(2)(p) = 0.26, bone mineral density F(1, 24) = 6.68, p = 0.02, eta(2)(p) = 0.22, waist circumference F(1, 24) = 10.35, p = 0.01, eta(2)(p) = 0.30, triglycerides F(1, 24) = 5.06, p = 0.03, eta(2)(p) = 0.17, and systolic blood pressure F(1, 24) = 5.39, p = 0.03, eta(2)(p) = 0.18 all in favor of the motivational interviewing group after 12 weeks when compared to the self-regulation-based mobile messaging group. No significant effect for group x time was noted for diastolic blood pressure p = 0.36, eta(2)(p) = 0.04, high-density cholesterol p = 0.08, eta(2)(p) = 0.12, or fasting blood glucose p = 0.85, eta(2)(p) = 0.01 when comparing the motivational interviewing and self-regulation-based mobile messaging groups. Conclusions: Motivational interviewing may be a more impactful solution to extend the effects of exercise intervention studies compared to a self-regulation-based mobile messaging control group. Future interventions should focus on increasing sample size, utilizing more objective measures of body composition, utilizing booster sessions, and increasing the length of follow-up periods.