Aerobic Exercise for Secondary Stroke Prevention: A Clinical Brief

As clinicians, we're constantly seeking the best ways to protect our patients from recurrent strokes. The evidence overwhelmingly points to aerobic exercise as a cornerstone of secondary prevention. But what does the latest research say about the specifics? How intensely, how often, and for how long should our patients be exercising? A recent systematic review and meta-analysis gives us some valuable insights. This 2025 meta-analysis by Harmon et al. looked at 27 randomized controlled trials involving patients in the subacute phase of stroke recovery (less than 6 months post-stroke). The big question was whether moderate to high-intensity aerobic exercise is both safe and effective in this population. The answer, in short, is a resounding yes. The study found that moderate to high-intensity exercise significantly improved several key measures of endurance and gait speed. Patients in the intervention groups saw a mean improvement of 33.11 meters in the 6-minute walk test, a clear indicator of improved cardiovascular fitness. They also showed a significant increase in peak work rate and faster gait speed. These are not just numbers on a page; they represent real-world improvements in our patients' ability to function and participate in their daily lives. So, what does a moderate to high-intensity exercise prescription look like? The interventions in the reviewed studies varied, but some common themes emerged. Moderate intensity was generally defined as 40-59% of heart rate reserve (HRR) or a Borg Rating of Perceived Exertion (RPE) of 12-14. High intensity was defined as 60-84% of HRR or an RPE of 14-16. The exercise sessions typically lasted for 20-40 minutes and were performed 3-5 times per week. It's important to note that many of the studies involved a gradual progression of intensity. Patients would often start at a lower intensity and work their way up as they became more fit. This is a crucial point for us as clinicians. We need to tailor our exercise prescriptions to the individual patient, taking into account their baseline fitness level and any comorbidities. A 'start low and go slow' approach is often the safest and most effective strategy. Of course, safety is always a primary concern, especially in the subacute phase of stroke recovery. The meta-analysis found no significant difference in the incidence of severe adverse cardiac or cerebral events between the intervention and control groups. This is a critical finding that should give us confidence in prescribing moderate to high-intensity exercise to our patients. However, it's also important to remember that the quality of evidence for this finding was rated as very low, and the authors recommend continued active monitoring for adverse events. In terms of patient selection, the studies included in the meta-analysis enrolled a broad range of patients in the subacute phase of stroke recovery. However, it's always important to conduct a thorough pre-participation screening to identify any contraindications to exercise. Patients with unstable cardiac conditions, uncontrolled hypertension, or other serious comorbidities may not be appropriate candidates for high-intensity exercise. In conclusion, the evidence from this meta-analysis strongly supports the use of moderate to high-intensity aerobic exercise for secondary stroke prevention in the subacute phase of recovery. By prescribing exercise at the right intensity, frequency, and duration, we can help our patients improve their cardiovascular fitness, reduce their risk of recurrent stroke, and regain their independence. It's a powerful tool in our clinical arsenal, and one that we should be using to its full potential.