Purpose: Short-to-moderate duration exercise training improves fitness and lowers cardiovascular risk in type 2 diabetes (T2DM). However, the impact of long-term compliance to an active lifestyle of T2DM patients on cardiovascular risk factors has never been studied but could provide information on the maximal achievable health effect of physical activity in T2DM. This study examined the impact of a life-long active lifestyle by comparing physical fitness, cardiovascular risk and vascular function between long-term physically active T2DM patients versus sedentary T2DM patients and controls.
Methods: Fitness, HOMA-IR, brachial artery flow-mediated dilation (FMD) and lifetime risk for cardiovascular disease were assessed in 15 exercising T2DM patients, 12 age-, sex- and weight-matched sedentary T2DM patients and 9 sedentary men free of established cardiovascular and metabolic disease as controls. Long-term regular exercise was defined as self-reported participation of >2.5 h of (predominantly) endurance exercise per week, which was performed for 18-47 years.
Results: Sedentary T2DM patients showed lower fitness (21.8 ± 2.3, 32.6 ± 6.0 and 31.1 ± 3.2 ml O2/kg/min), higher HOMA-IR (8.3 ± 5.0, 2.0 ± 1.8 and 1.1 ± 0.5 100/%S) and higher lifetime risk scores (17.3 ± 5.4, 9.3 ± 5.0 and 8.9 ± 3.9 %) compared to active peers and controls, respectively. Brachial artery FMD was lower in sedentary T2DM patients compared with active peers, but not in controls (3.3 ± 1.2, 5.2 ± 2.1 and 3.8 ± 1.2%).
Conclusions: Life-long active T2DM patients have superior fitness levels, HOMA-IR, cardiovascular risk and FMD compared to sedentary peers, whilst no differences were found when compared to controls. This study provides evidence that a life-long active lifestyle, even in T2DM, may be able to effectively normalize cardiovascular risk.