Study protocol for a feasibility randomised controlled trial of MOVE SMART-An intervention to increase physical activity, reduce sedentary behaviour and improve health outcomes in patients with psoriasis.

Patients with psoriasis are less physically active than age-matched controls due to psoriasis-specific barriers.

• Psoriasis-specific barriers significantly limit patients' ability to benefit from health-promoting levels of physical activity.
• Prior proof-of-concept studies co-designed with patients showed improved psoriasis, reduced cardiovascular disease/metabolic syndrome risk, and enhanced wellbeing/psychosocial functioning from exercise interventions.
• Individuals in prior studies remained sedentary for prolonged periods even after exercise intervention, motivating development of the new MOVE SMART approach.

The MOVE SMART intervention prompts 2 minutes of light-intensity physical activity following every 30 minutes of continuous sedentary behaviour during daytime waking hours.

• The intervention was designed to both increase light-intensity physical activity and interrupt sedentary behaviour.
• Participants follow MOVE SMART for 12 weeks, followed by activities of their own choice during weeks 13–24.
• The intervention is delivered as part of a 'Standard Care' plus MOVE SMART regimen in the intervention arm.

The trial is a decentralised, two-arm, feasibility randomised controlled trial recruiting 60 participants with Type 1 psoriasis from across the UK.

• Participants (n = 60) include people with Type 1 psoriasis with or without stable psoriatic arthritis.
• Participants are randomised to intervention (MOVE SMART with Standard Care, n = 30) or control (Standard Care only, n = 30).
• The decentralised design allows recruitment from across the UK without requiring in-person site visits.
• The study is registered at www.isrctn.com (ISRCTN 17400289).

The trial comprises three workstreams covering physical monitoring, acceptability evaluation, and trial design finalisation.

• Workstream-1 involves wearable devices to monitor physical behaviour and adherence, a blood pressure monitor, body weight scales posted to participants, and functional capacity assessed by video-link.
• Assessments occur at baseline, week 12, and week 24, including self-assessment of psoriasis extent/impact and wellbeing.
• Capillary blood is collected using home-sampling kits at each assessment point.
• Workstream-2 evaluates acceptability of the intervention, and Workstream-3 finalises the full trial design based on feasibility findings.

The primary objective of the trial is to assess the feasibility and acceptability of the MOVE SMART intervention.

• The trial is explicitly described as a feasibility RCT, not powered to detect clinical efficacy.
• Outcomes include physical activity behaviour, sedentary behaviour, blood pressure, body weight, functional capacity, psoriasis severity, and wellbeing.
• The feasibility data will inform the design of a subsequent full-scale RCT (Workstream-3).