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Introduction Intermittent claudication (1C) is a vascular condition which limits the distance subjects can walk before experiencing pain in the lower limb calf muscles due to limitation of vascular supply. Orthotic intervention evidenced in the literature has previously included the use of rocker profiles or raised heels to increase the pain-free walking distance, but variable results have been demonstrated. This study aims to design a rocker profile with the specific objectives of increasing the pain free walking distance demonstrated by claudicants and reducing their calf pain once claudicating. Method Twelve volunteer healthy subjects, age range 25 to 54 years (mean: 32.7 +/- 11.3), initially undertook separate walking trials in gait laboratory conditions with shoes adapted with three different rocker sole profiles; the one-curve toe-only profile, the two-curve profile and the three-curve profile, plus a shoe adapted with a moderate (12mm) heel raise. Measurements and comparisons of gait kinetics and kinematics (Qualysis, Sweden), and the electromyographical (EMG) activity (Noraxon, USA) of the medial and lateral gastrocnemius muscles, plus that of soleus and tibialis anterior, were undertaken. The most effective condition compared to a baseline un-adapted shoe was then tested during walking trials with claudicants (n=8, mean age 66 +/- 9 years) to ascertain its efficacy in reducing the pain-free walking distance to claudication and the severity of the pain once claudicating. Results All changes from the baseline shoe were set at a level of significance of p<0.05 The three-curve rocker profile placed the ankle joint into a relatively plantarflexed position compared to baseline at loading response (/?=0.00), mid stance (p=0.00) and terminal stance (/?=0.00), and significantly reduced total sagittal plane ankle range of motion compared to baseline (/7=0.00). The moderate heel raise also induced ankle plantarflexion at loading response (p=0.00) but increased ankle range of motion during second rotational phase of gait (/?=0.00) compared to baseline. The one-curve rocker profile induced a sagittal plane dorsiflexion shift at the ankle during mid stance (/?=0.00). The three-curve rocker profile was the most effective test condition in reducing both the externally-applied ankle dorsiflexion moment (/?=0.00) and ankle power generation (p=0.00) during stance phase of gait compared to baseline. Changes to muscle EMG values by all the test conditions were not statistically significant. Claudicant walking trials when wearing the three curve rocker profile demonstrated a statistically significant increase in pain-free walking distance to claudication (/?=0.00) and a reduction in claudication pain once claudicating (/?=0.00). Conclusion This study demonstrates that a specifically-designed rocker profile can significantly alter gait kinetics and kinematics and produce a statistically different increase in the pain-free walking distance of claudicants whilst also significantly reducing their pain levels once claudicating.