Finding the Optimal volume and intensity of Resistance Training Exercise for Type 2 Diabetes: The FORTE Study, a Randomized Trial.

AIM

To compare different volumes and intensities of resistance training (RT) combined with aerobic training (AT) for improvements in glycemic control and cardiovascular health for persons with type 2 diabetes (T2DM).

METHODS

Participants with T2DM were stratified by HbA1c and randomized: "usual care" (RT1), which consisted of moderate intensity (50% 1-repetition maximum [1-RM]), low volumeRT (initiated half-way through program); higher intensity (75% 1-RM) and higher volume (initiated at program onset) RT (RT2); or moderate intensity but higher volume RT (RT3). RT sets and repetitions were adjusted to maintain similar work and volume between RT2 and RT3. Walking or cycling (60-80% aerobic capacity)was prescribed 5 times/week, and RT was prescribed 2 times/week. An ANCOVA, adjusted for baseline and gender, assessed changes post-6months in glycemic control (HbA1c- primary outcome), aerobic capacity and anthropometrics.

RESULTS

Sixty-two participants (52.3±1.2years, 48% female) were randomized (RT1, n=20; RT2, n=20; RT3, n=22). Only post-training fasting glucose, without significant HbA1c change, was different between groups (RT1-RT3=-1.7mmol/L, p=0.046). Pre-post differences were found in pooled HbA1c (7.4±0.2%[57±2.2mmol/mol] vs. 6.7±0.2%[50±2.2mmol/mol], p<0.001), aerobic capacity (21.5±0.8vs. 25.2±0.8ml/kg/min, p<0.001), body mass (84.0±2.7vs. 83.0±2.7kg, p=0.022[DXA]), body mass index (30.8±0.9vs. 30.3±0.8kg/m, p=0.02) and body fat (32.3±1.1vs. 31.3±1.2%, p<0.001). The trial was discontinued early; no HbA1c advantage was found with either RT2 or RT3 over RT1.

CONCLUSIONS

Combined AT+RT exercise improved glycemic control, cardiovascular risk factors and body composition after 6months for participants with T2DM, but differential effects between the prescribed intensities and volumes of RT were not found to effect HbA1c.