Abstract Objectives Assess the feasibility of embedding an exercise specialist-led, mHealth-supported physical activity and exercise intervention (MOTIVATE-CEW) into a UK Complications from Excess Weight (CEW) service. Design Feasibility, single-site, parallel-group randomised controlled trial. Setting Participants were recruited from Alder Hey Children’s Hospital (AHCH) CEW service. Patients Young people (12–18 years) receiving care from the AHCH CEW service.