Table 1. Schedule of participant assessments.

Milestones	Activity	Prescreen	Screen	Baseline(preintervention)	Mid-intervention	Postintervention	Post off-treatment period
Week		−4 to −1	−1	0	6	12	18
Visit (time point)		1	2	3–4	5	6–7	8–9
Recruitment	Patient identification	X
	Prescreen checklist for eligibility	X
Enrolment and screening	Consent	X
	Confirm eligibility criteria (ABI, ECQ)	X
	Demographics and health history	X
	Blood pathology tests	X
Medical review familiarisation, randomisation	Treadmill walk test with ECG, medical review		X
	Familiarisation with 6 min walk and vascular tests		X
	Randomisation			X
	Set up and familiarisation with intervention device			X
Interventions	Daily footplate NMES (weeks 1–12)
	Daily footplate placebo CON (weeks 1–12)
Off-treatment	Off-treatment follow-up period (weeks 13–18)
Primary outcome	6 min walk test			X	X	X	X
Secondary outcomes	Quality of life and function (WIQ, ICQ)			X	X	X	X
	Treadmill walking test			X		X	X
	Physical activity (7-day accelerometer)		X			X	X
Exploratory outcomes	ABI			X		X	X
	Leg blood flow and vascular function			X		X	X
Monitoring and compliance	Symptoms (CSI, VAS) (weeks 0, 1, 3, 6, 9, 12, 18)						X
	Device experience (weeks 1 and 12)			X		X
	Device diary and data log (daily, weeks 1–12)
	Telephone monitoring and support, unblinded(weeks 1, 3, 6, 9, 12)

All participants will continue to receive usual care and medical advice from their general practitioner (local doctor) and vascular surgeon, and they will be randomly allocated to the NMES programme () or placebo controlCON programprogramme () for 12 weeks. Outcome measures will be assessed at baseline (week 0), midway through (week 6) and at the end of the intervention period (week 12), and again at the end of the 6-week off-intervention phase (week 18). The six6 min walk test and the treadmill walking test will always be conducted during separate visits at each assessment time point. Telephone monitoring calls will be made at weeks 1, 3, 6, 9, and 12.

ABI, Ankle-Brachial Index; CONplacebo controlCSI, Claudication Symptom Instrument; ECQ, Edinburgh Claudication Questionnaire; ICQ, Intermittent Claudication Questionnaire; NMESneuromuscular electrical stimulationVAS, Visual Analogue ScaleWIQ, Walking Impairment Questionnaire