PURPOSE: To evaluate the feasibility and effects of an exercise programme on people with severe, chronic schizophrenia. METHOD: A single-group, pre-post pilot study incorporating a baseline familiarisation phase was followed by a 24-week, small-group aerobic exercise programme for up to 30-min each session, twice a week and a 30-min weekly walking session. Adherence was assessed by attendance, and by analysing the exercise supervisor's comments in a programme diary and in each participant's exercise logbook. Body weight, cardio-respiratory fitness (VO₂ max), walking endurance (6-min walk test) and psychiatric symptoms (the Positive and Negative Syndrome Scale) were measured at each time point. RESULTS: Eight participants (6 men, 2 women; mean age 45 years, 9 months (SD 10 years, 1 month); mean body mass index 27.0 (SD 4.2)) attended a mean of 73% of the scheduled exercise sessions, and 83% of the walking sessions, with no adverse events and no dropouts. All participants displayed positive and negative behaviours during training sessions. There were significant reductions in weight (2.4%) and body mass index (2.2%), but no changes in other measures. CONCLUSIONS: It was feasible and safe to conduct a small-group aerobic exercise programme for adults with severe chronic schizophrenia that reduced body weight.