169-OR: Differential Effects of Amount, Intensity, and Mode of Exercise Training on the Diabetes Risk Index

Objective: Examine the effects of amount, intensity, and mode of exercise training on type 2 diabetes (T2D) risk.Methods: A total of 531 men and women with dyslipidemia [STRRIDE I (n=222), STRRIDE AT/RT (n=142) or prediabetes [STRRIDE-PD (n=167)] were randomized to control group or one of 10 exercise interventions, ranging from doses of 8-22 kcal/kg/week; intensities of 50-75% V?O2peak; and duration of 6-9 months. Two groups included resistance training and one included dietary intervention (weight loss goal of 7%). Fasting plasma samples were obtained at baseline and 16-24 h after last exercise bout. The Diabetes Risk Index (DRI) and its components—Lipoprotein Insulin Resistance Index (LP-IR) and branched chain amino acids (BCAA) valine and leucine—were determined by NMR spectroscopy. DRI scores range from 1-100, the latter representing those at greatest T2D risk. Paired t-tests determined significance within groups (p<0.05). Study-specific ANCOVA determined differences among groups.Results: The inactive control group did not significantly change DRI score. After training, four of ten exercise groups significantly improved DRI scores, ranging from -2.8 ± 8.2 to -8.3 ± 10.4. In STRRIDE AT/RT, only the aerobic-plus-resistance group significantly improved DRI. In STRRIDE-PD, the moderate-intensity-plus-diet group had a greater DRI change than the other exercise-only moderate intensity groups. Reductions in DRI appeared to be driven largely by decreases in insulin resistance (LP-IR) but not dysmetabolism (BCAA), except for the moderate-intensity-plus-diet group, which exhibited a reduction in both.Conclusions: Multiple exercise interventions led to improvements in DRI scores. Results provide compelling evidence that adding resistance to aerobic training elicits a synergistic effect on insulin resistance and T2D risk. In individuals with prediabetes, incorporating dietary intervention with aerobic training results in the most robust improvement in T2D risk.

Duke Scholars

Author Leanna Ross Medicine, Cardiology