Background: Stroke is a complex disease that can vary in severity. After a stroke, patients often have long-term disabilities that require major rehabilitation efforts. Evaluation of treatment and methods are important for development of effective rehabilitation after stroke. Various forms of physiotherapy interventions have been tested in different phases after stroke, but there are still questions about timing and forms of exercise. In this work, aerobic exercise with an ergometer cycle and an in-bed cycle were used as models for intervention in subacute and acute phase after stroke. Exercise has been evaluated both after discharge from hospital and in hospital care. Aim: The overall aim of the dissertation was to study the effects of exercise in different phases after stroke of varying severity.

Method: Two studies were performed in Swedish stroke units during 2013- 2018. Both studies were randomized controlled trials focusing on the effects of exercise in different phases after stroke. Study A included 56 patients with mild stroke from one hospital. Patients were discharged from the hospital and enrolled to intervention in median 22.5 days after stroke onset. All patients received usual care in a stroke unit according to national guidelines, and the intervention group received additionally aerobic exercise for 1 hour 2 times per week for 12 weeks post-discharge. The session included 2x8 minutes of intense aerobic exercise on an ergometer cycle. In study A, the effects of exercise were evaluated by aerobic exercise, walking distance and hemodynamic responses and compared to usual care.

Study B included 52 patients in the acute phase of moderate to severe stroke from two hospitals. Patients were enrolled to intervention 2 days after onset, and all patients received usual care. In addition to usual care, one group received in-bed cycle exercise 20 minutes daily, 5 days per week for 3 weeks. In study B, the effects of exercise were evaluated by walking distance and hemodynamic responses and compared to usual care.

Results: Study A showed that intensive aerobic exercise twice weekly for 12 weeks during the subacute phase of mild stroke improved the patient’s aerobic capacity and walking distance after the intervention period. The study also showed that exaggerated blood pressure reactions associated with exercise were common in the subacute phase but not significantly affected by participation in a 12-week exercise period.

Study B showed that the addition of in-bed cycle exercise in the acute phase after more severe stroke was not superior to usual care with regards to walking distance after 3 months. From baseline to post-intervention, systolic blood pressure decreased significantly to a similar extent in both groups, but the exercise group seemed to normalize their blood pressure response to exercise to a greater extent than patients in the control group.

Conclusion: For patients with mild symptoms, aerobic exercise initiated 3 weeks after stroke onset was beneficial for aerobic capacity and walking distance. In the acute phase after stroke, starting two days after onset, 3 weeks 4 of in-bed cycle exercise was not superior to usual care with regards to walking distance after 3 months. Exercise-related exaggerated blood pressure reactions were common in the subacute phase but not affected by participation in a 12- week exercise period. An effect of the in-bed cycle exercise in the acute phase after stroke seemed to be that patients randomized to the intervention normalized their blood pressure reaction in connection with exercise.