Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are increasingly used in tertiary obesity services to achieve clinically meaningful weight loss. Despite their effectiveness, concerns remain regarding reductions in lean muscle mass and subsequent declines in physical function during rapid weight loss. Exercise is recommended alongside pharmacotherapy; however, there is limited real-world evidence demonstrating whether functional capacity can be maintained or improved. This study aimed to evaluate functional outcomes in adults receiving GLP-1 therapy while participating in a physiotherapist-led exercise programme within a multidisciplinary weight management service.
Twenty-seven participants receiving semaglutide or tirzepatide through the Tertiary Obesity Multidisciplinary Service (TOMS) at the Royal Brisbane and Women's Hospital were reviewed during the 2025–2026 period. Participants completed a 12-week Very Low Energy Diet (VLED) alongside a structured exercise programme consisting of weekly one-hour supervised strength class, home exercise programme comprising two days of cardiovascular exercise and three days of resistance training each week. Functional outcomes were assessed at baseline and week 12 using grip strength (kg), six-minute walk test (6MWT; metres) and 30-second sit-to-stand (STS; repetitions). Body weight was recorded pre- and post-intervention.
Participants lost an average of 17.5 kg, representing 12.7% body weight loss. Despite substantial weight reduction, significant improvements were observed across all functional outcomes. Six-minute walk distance improved by 118.4 metres (347.5 to 465.9 m; p < 0.001), clinically meaningful improvement ≥30 m. Thirty-second sit-to-stand improved by 6.7 repetitions (10.3 to 17.1 repetitions; p < 0.001), clinically important threshold ≥2 repetitions. Grip strength increased by 5.4 kg (30.8 to 36.2 kg; p < 0.001), clinically meaningful threshold ≥5 kg.
Adults receiving GLP-1 therapy demonstrated statistically and clinically significant improvements in functional capacity despite substantial weight loss. These findings support the integration of structured physiotherapy-led resistance training within multidisciplinary obesity services to optimise functional outcomes during GLP-1-assisted weight management.