The impact of different supervised exercise regimens on endothelial function in patients with intermittent claudication

Background and objectives: The impact of supervised exercise training on endothelial function in patients with intermittent claudication is unclear. This study assesses the impact of treadmill-based supervised exercise training alone or in combination with resistance training on pain free walking distance, flow-mediated dilatation, reactive hyperaemia index, nitric oxide and asymmetric dimethylarginine. Methods: Thirty-five patients with intermittent claudication were randomised to 12 weeks of treadmill-only supervised exercise training (Group 1) or a combination of treadmill and lower-limb resistance supervised exercise training (Group 2). Pain free walking distance was assessed by six-minute walk test. Endothelial function was assessed by brachial artery flow-mediated dilatation, reactive hyperaemia index and serum analysis of asymmetric dimethylarginine and nitric oxide. Results: Pain free walking distance improved within Group 1 (160m to 204m, p=0.03) but not Group 2 (181m to 188m, p=0.82), no between group difference. No significant change in flow-mediated dilatation or reactive hyperaemia index in either group. Nitric oxide decreased in Group 1 (15.0 mu mol/L to 8.3 mu mol/L, p=0.003) but not Group 2 (11.2 mu mol/L to 9.1 mu mol/L, p=0.14), p=0.07 between groups. Asymmetric dimethylarginine decreased in Group 2 (0.61 mu mol/L to 0.56 mu mol/L, p=0.03) but not Group 1 (0.58 mu mol/l to 0.58 mu mol/L, p=0.776), no between group difference. Conclusion: Supervised exercise training does not improve endothelial function as measured by flow-mediated dilatation, reactive hyperaemia index and nitric oxide bioavailability.