Effect of Exercise on Blood Pressure in Type 2 Diabetes: A Randomized Controlled Trial

Increased blood pressure (BP) in type 2 diabetes (T2DM) markedly increases cardiovascular disease morbidity and mortality risk compared to having increased BP alone. To investigate whether exercise reduces suboptimal levels of untreated suboptimal BP or treated hypertension. Prospective, randomized controlled trial for 6 months. Single center in Baltimore, MD, USA. 140 participants with T2DM not requiring insulin and untreated SBP of 120-159 or DBP of 85-99 mmHg, or, if being treated for hypertension, any SBP < 159 mmHg or DBP < 99 mmHg; 114 completed the study. Supervised exercise, 3 times per week for 6 months compared with general advice about physical activity. Resting SBP and DBP (primary outcome); diabetes status, arterial stiffness assessed as carotid-femoral pulse-wave velocity (PWV), body composition and fitness (secondary outcomes). Overall baseline BP was 126.8 +/- 13.5 / 71.7 +/- 9.0 mmHg, with no group differences. At 6 months, BP was unchanged from baseline in either group, BP 125.8 +/- 13.2 / 70.7 +/- 8.8 mmHg in controls; and 126.0 +/- 14.2 / 70.3 +/- 9.0 mmHg in exercisers, despite attaining a training effects as evidenced by increased aerobic and strength fitness and lean mass and reduced fat mass (all p < 0.05), Overall baseline PWV was 959.9 +/- 333.1 cm/s, with no group difference. At 6-months, PWV did not change and was not different between group; exercisers, 923.7 +/- 319.8 cm/s, 905.5 +/- 344.7, controls. A completion rate of 81 %. Though exercisers improve fitness and body composition, there were no reductions in BP. The lack of change in arterial stiffness suggests a resistance to exercise-induced BP reduction in persons with T2DM.