Feasibility of Aerobic Interval Training in Nonambulant Persons after Stroke

Background: Modifiable cardiovascular risk factors are prevalent and poorly managed in people after stroke. Aerobic exercise is effective in reducing many modifiable cardiovascular risk factors after stroke but is challenging and under-researched in nonambulant persons. This pilot study aimed to investigate the feasibility of aerobic interval training in nonambulant persons after stroke. Methods: Aerobic exercise was performed on an upright or semi-recumbent cycle ergometer. Participants were prescribed 4 × 4-min intervals of exercise at 85% maximum age-predicted heart rate (APHRmax) with a 3-min active recovery at 70%APHRmax per 30-min session, 3 times per week for 10 weeks. Heart rate, rating of perceived exertion, workload, cadence, and duration of exercise achieved were recorded for each interval. Results: Nine participants (mean ± SD; age 62 ± 12 y; 5 males) unable to walk without assistance after stroke (2.9 ± 3.9 y) were recruited. There were no adverse events reported, but there was one dropout (due to bronchitis). Attendance for the remaining participants was 93 ± 6%. The mean training %APHRmax was 72 ± 14% for the higher intensity interval and 57 ± 21% for the recovery interval. The mean increase in training workload between weeks 1 and 10 was 11.2 ± 11.6 W (27 ± 28%) for the higher intensity interval and 4.0 ± 7.7W (17 ± 33%) for the recovery interval. The mean increase in VO2peak was 2.3 ± 2.9 mL·kg−1·min−1 (18 ± 22%) over the 10-week intervention. Conclusion: Aerobic interval training at a moderate-vigorous intensity on an upright or recumbent cycle ergometer is feasible for nonambulant persons after stroke. Aerobic interval training should be further investigated to determine its potential to improve cardiorespiratory fitness after stroke and risk factors for recurrent stroke.