What to Expect From Exercise

Mixed messages are sometimes sent about the risks and benefits of exercise for people with chronic HIV infection. What looks like a risk or benefit for a noninfected group may be more or less so for HIV-infected individuals. This overview should provide you with some of the information to mull over in making decisions about exercise. Is the immune system weakened after exercise? Previous evidence suggested there was a challenge to the immune systems of HIV-infected individuals after periods of exercise. Since that time several groups have studied the potential risks and benefits of various forms of exercise. We now understand that the range of benefits of consistent exercise may include lower viral loads, slower progression of disease and fewer symptoms, and greater survival numbers. Also, exercise yields few to no negative effects on'or some improvement in'CD4 counts. Does exercise help with strength and endurance? Observational studies have suggested an initially lower level of strength and endurance in HIV-infected people who do not exercise. As it turns out, even with HIV infection, the body responds to exercise by increasing both muscle and endurance. Progressive resistance exercise increases muscle volume and strength, while aerobic exercise increases stamina. Does exercise play a role in the treatment of lipodystrophy? While exercise can certainly improve body composition in general, the question of how it works when someone has body-shape changes may bring up some concerns. For the fat-gain side of the coin, some reduction may be seen in abdominal fat accumulation, while peripheral subcutaneous fat may stay pretty static. Care should be taken to make sure that weight remains steady during the exercise process by matching activity increases with calorie increases to prevent unwanted weight loss. What about psychological stress? Exercise can help to reverse some sources of depression and fatigue. Surveys have shown that aerobic exercise is related to improvement in quality of life. Not all studies have reported glowing results, but even no significant improvement is better than moving backward. What should I do to set up a physical activity program? Remember that any improvement in physical activity may prove beneficial in several ways. As with most changes in therapy, you should get your doctor's review and clearance. To set up something that may provide you with some good specific activities and goals, ask for a referral to a physical therapist or clinical exercise physiologist for an evaluation and exercise prescription. This prescription should detail types of exercises and the time to be spent doing them as well as the number and kind of resistance-exercise repetitions you should do to achieve your goals of improving muscle function and strength. You should also be 'under observation' during the first few sessions to make sure that you tolerate the exercise well and keep the risk for injury low. What types of physical activity and intensity should be expected? There are a few general concepts. (1) Start slowly, especially if you are not used to much physical activity. Start with an aerobic exercise program to build endurance for the first four to six weeks before adding resistance exercise. (2) Increase the duration of your exercise sessions to between 20 and 60 minutes. If you face some physical limitations, try intermittent 10-minute sessions to total 20 to 60 minutes until endurance and tolerance builds. (3) Increase the level of exercise to 'moderate' (50% to 80% of peak heart rate). Your level of exertion should be comparable to walking at three miles per hour, gardening or mowing the lawn with a power mower, golf (carrying clubs and walking, of course), bicycling at a fairly leisurely pace (less than 10 miles per hour), or dancing at a moderate level. So check with your doctor and let's get cracking! Fields-Gardner is the director of services for The Cutting Edge, an HIV nutrition company in the Chicago area. She is a member of the International AIDS Society and the American Dietetic Association's Dietetic Practice Group on HIV and AIDS. She has written a book on HIV medications and a guide to nutritional management of HIV for clinicians.