Exercise is an integral part of many forms of rehabilitationfollowing muscle injury or surgery. It is usual to advise patients with a viral infection to avoid exercise because of the risk of developing myocarditis. Should HIV+ patients should be encouraged to undertake exercise as part of rehabilitation and should they further be advised to participate in regular exercise? There is sufficient evidence to support the benefits of regular exercise in the HIV+ patient. They will experience a training effect dependent on the normal parameters of frequency, intensity, duration, and mode of exercise.  The disease does place potential limitations to exercise, as the HI virus directly affects pulmonary, cardiac, skeletal muscle and endocrine function.  The effects of these changes may be  exacerbated by secondary infection and other pathological changes may be induced by treatment.  The advent of highly active antiretroviral therapy has brought with it a range of metabolic changes that may also influence exercise  participation. The limitations to exercise imposed by HIV infection and its treatment are reviewed.