OBJECTIVE:This study examined the feasibility of a parallel-group assessor-blinded randomized controlled trial investigating whether task-specific training preceded by aerobic exercise (AEX + TST) improves upper limb function more than task-specific training (TST) alone. METHODS:People with upper limb motor dysfunction after stroke were allocated to TST or AEX + TST. Both groups were prescribed 60 hr of TST over 10 weeks (3 × 1-hr sessions with a therapist per week and 3 × 1 hr of home-based self-practice per week). The AEX + TST group performed 30 minutes of aerobic exercise immediately prior to the 1 hr of TST with the therapist. Recruitment, adherence, retention, participant acceptability, and adverse events were recorded. Clinical measures were performed prerandomization at baseline, on completion of the intervention, and at 1- and 6-month follow-up. RESULTS:Fifty-nine persons after stroke were screened, 42 met the eligibility criteria, and 20 (11 male; mean [SD] age: 55.4 [16.0] years; time since stroke: 71.7 [91.2] months) were recruited over 17 months. The mean Wolf Motor Function Test Functional Ability Score at baseline was 27.4 (max = 75) and the mean Action Research Arm Test score was 11.2 (max = 57). Nine were randomized to AEX + TST and 11 to TST. There were no adverse events, but there was one drop out. Retention at 1- and 6-month follow-up was 80% and 85%, respectively. Attendance was 93% (6) for the AEX + TST group, and 89% (9) for the TST group. AEX + TST was perceived as acceptable (100%) and beneficial (87.5%). Exertional fatigue (visual analogue scale) prior to TST was worse in the AEX + TST group (3.5 [0.7] out of 10) than the TST group (1.7 [1.4] out of 10). The TST group performed 31% more repetitions per session than the AEX + TST group. CONCLUSION:A subsequent Phase III study is feasible, but modifications to eligibility criteria, outcome measures, and intervention delivery are recommended.