Supervised exercise training is part of first-line therapies for intermittent claudication. Short periods of intensive treadmill training have been found efficient; however, the optimal modalities remain to be determined, especially interval training with active recovery (ITAR). In this prospective assessor-blinded single-centre pilot study, we assessed the feasibility of a randomised controlled trial comparing parallel 4-week intensive rehabilitation programs comprising treadmill training performed as ITAR or conventional training with constant slope and speed interspersed with rest periods (CT).

A total of 38 in- or out-patients were randomised to the ITAR or CT program for 5 days/week for 4weeks. The primary outcome was change in maximum walking distance measured on a graded treadmill before and after the program.

Adherence was high. All training sessions were completed in the ITAR program and only a few were not completed in the CT program (median 100% [Q1–Q3 96–100]). Tolerance was excellent (no adverse events). VO_2peak was low in both groups, corresponding to moderate to severe exercise intolerance. The 2 groups did not differ in the primary outcome (median ITAR vs CT 480 [135–715] vs 315m [0–710]; p=0.62) or other walking distances (constant speed and gradient treadmill test). For all 38 participants, both programs greatly increased maximum walking distance in the graded treadmill test: median 415 [240–650] to 995m [410–1490], with a large effect size (p<10⁻⁴).

A 4-week intensive rehabilitation program with ITAR or CT for intermittent claudication showed high adherence, was well tolerated, and improved walking distance as much as that reported for longer conventional programs. These findings prompt the design of a larger multicenter randomised controlled trial.

NCT01734603