Peripheral vascular disease (PVD) of the lower limbs is most apparent during ambulation, when ischaemic pain (intermittent claudication) elicits early exercise cessation. Functional capacity in claudicants was enhanced by a 4 week period of low frequency electrical stimulation of calf muscles, evidenced by increases in treadmill claudication (CD) and maximal walking (WD) distances, but improvements were not maintained when stimulation ceased (Tsang et al. 1994, Anderson et al., 2004). For stimulation to be considered an effective treatment for PVD, improved functional capacity must be sustainable. We therefore investigated whether repeating stimulation after a rest period would achieve this. Following habituation with the assessment protocols, 8 stable intermittent claudication patients, aged 70±2 years (mean±S.E.M.) were randomised into active low frequency (8Hz) stimulation or control (TENS) treatment groups. Treatment lasted for a fixed period of 20mins, 3 times per day for 4 weeks (Bout1), with a repeat regimen (Bout2) applied after a 2 week rest period (total study duration 14 weeks). Functional capacity was assessed using treadmill measures, with lower limb blood flow estimated by venous congestion plethysmography. Approval for the study was obtained from the South Birmingham Research Ethics Committee, and University Hospital Birmingham, NHS Trust. Four weeks active stimulation (Bout1) led to an 18% increase in pain-free walking distance from baseline (310±59 vs. 260±71 m, P〈0.05, paired t test), with a similar improvement in WD. Following a period of 2 weeks rest, improvements in CD and WD had waned by approximately 15 m. A repeat regimen of stimulation (Bout2) reversed the decline in CD and WD after the rest period, and reinstated values back to those seen after the first stimulation period. Lower limb blood flow increased from baseline after Bout1 (3.5±0.6 vs. 2.1±0.3ml.min^-1 (100ml)^-1, P〈0.05) and did not decline over 2 weeks rest. Flow increased further after Bout2 (5.7±1.0ml.min^-1 (100ml)^-1), and remained 92% above pre-treatment values at the end of the study. TENS did not induce improvements on any measure. Chronic low frequency electrical stimulation of ischaemic calf muscles is therefore an effective stimulus for transient improvements in functional capacity in PVD. Applied intermittently, it enables improved functional capacity to be sustainable. We also show that stimulation provides amelioration of the haemodynamic compromise experienced by claudication patients