Changes in Body Fat Distribution and Fitness Are Associated With Changes in Hemoglobin A(1c) After 9 Months of Exercise Training: Results from the HART-D study
Article
Senechal, Martin; Swift, Damon L.; Johannsen, Neil M.; Blair, Steven N.; Earnest, Conrad P.; Lavie, Carl J.; Church, Timothy S.
Abstract
OBJECTIVE To investigate the associations between changes in body composition and fitness after exercise training and changes in hemoglobin A(1c) (HbA(1c)) in individuals with type 2 diabetes.RESEARCH DESIGN AND METHODS Participants (n = 201) were randomized to aerobic, resistance, or combined training for 9 months. HbA(1c), waist circumference, total and trunk fat mass, appendicular fat mass, lean body mass, isokinetic leg muscle strength, peak O-2 uptake, and estimated METs were assessed at baseline and follow-up. Change in HbA(1c) was evaluated across quartiles of change in body composition and fitness.RESULTS Change in HbA(1c) was associated with changes in body weight (r = 0.13, P = 0.052), waist circumference (r = 0.17, P = 0.013), trunk fat mass (r = 0.19, P = 0.005), and estimated METs (r = -0.16, P = 0.023). There was a trend in change in HbA(1c) across quartiles of waist circumference (P = 0.011), trunk fat mass (P = 0.020), and estimated METs (P = 0.011). Participants with increased estimated METs and reduced trunk fat mass had greater odds of having reduced HbA(1c) after training (3.48, 1.46-8.31). Finally, participants with increased estimated METs and reduced waist circumference were 2.81 (1.13-6.98) times more likely to have reduced HbA(1c) and type 2 diabetes medication use than those without improved fitness and central adiposity.CONCLUSIONS In patients with type 2 diabetes, a reduction in central adiposity and increase in fitness were the most prominent predictors of the change in HbA(1c) in response to exercise training.
