Long-term Effects Of Exercise On Cardiovascular Disease Risk Profile Following Weight Loss In Overweight Women

Abstract

Despite the widely recognized benefits of weight loss, minimal research has examined the longitudinal effects of exercise training on cardiovascular disease (CVD) risk factors after weight loss. PURPOSE: To evaluate the long-term influence of exercise training on CVD risk factors after weight loss in previously overweight women. METHODS: A randomized weight loss trial was conducted in 64 premenopausal women (BMI 28.3±1.2 kg/m2; age 33.7±6.4 yrs). Participants were assigned to either aerobic training (AT: continuous treadmill exercise at 67-80% of maximum heart rate), resistance training (RT: 10 total body exercises at 65-80% of 1-RM), or control (C: no exercise). All groups consumed a standardized diet until achieving BMI <25kg/m2. Exercise groups trained 3x/wk during the weight loss period and were encouraged to exercise 2x/wk for one yr following the initial weight loss. Body weight, % body fat, abdominal fat, resting blood pressure (BP), insulin sensitivity, total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, and triglycerides (TG) were measured. Two-way repeated measures ANOVA was used to analyze dependent variables at baseline, post-intervention, 1 yr post intervention, and 3 yrs post intervention. Post hoc paired sample t-tests were used to examine changes from baseline to 3 yrs post intervention. Significance was accepted at p≤0.05. RESULTS: Mean weight loss for all subjects was 11.92 kg. Significant group x time interactions were found for body weight, % body fat, systolic BP, TG, HDL, and TC:HDL ratio, with no significant interactions for any other variable. Three yrs after weight loss, body weight (74.9.4±5.7 to 71.1±9.6 kg), body fat (39.7±3.9 to 35.9±6.2 %), systolic BP (120.0±13.0 to 111.4±8.0 mmHg), HDL (42.0±13.4 to 55.1±11.9 mg/dL), and TC:HDL ratio (4.2±1.6 to 3.3±1.2 mg/dL) were significantly improved from baseline in AT. TG (87.5±32.2 to 74.3±27.0 mg/dL), HDL (41.2±8.9 to 49.4±13.4 mg/dL), and TC:HDL ratio (3.9±0.8 to 3.5±0.8 mg/dL) significantly improved from baseline in RT. C had no differences. CONCLUSIONS: Three yrs after initial weight loss, several CVD risk factors were more favorable in women who exercise trained compared to non-exercisers. Further longitudinal research examining the effects of exercise on the maintenance of improved CVD risk factors is warranted.