For most people, light activity such as short walks and gentle stretching is encouraged within days of leaving hospital. More structured exercise usually begins after a cardiac rehabilitation assessment, typically four to six weeks after the event. A return to sport needs explicit clearance from your cardiologist, and the timescale varies by activity.
If you have an ICD, avoid overhead arm movements and strenuous upper body exercise for the first four to six weeks after implantation, so the leads can settle. Your device clinic will advise you specifically.
Do not wait until you feel completely well before starting to move. Prolonged rest does not help cardiac recovery, and gradual activity rebuilds both fitness and confidence. Our guide to exercise after cardiac arrest covers this in more detail.