NATAP: Exercise Good for Heart & Nervous System

[Guest guest]

NATAP - www.natap.org

Exercise good for the heart, nervous system in HIV patients

By Rauscher

NEW YORK (Reuters Health) - Moderate aerobic exercise significantly improves arterial compliance and autonomic nervous system function in HIV-infected patients, according to findings presented Sunday at the 35th Congress of the International Union of Physiological Sciences in San Diego, sessions of Experimental Biology 2005.

"Our study shows that even those with HIV should be exercising. It's not just good for their health, but it also improves their physiology in terms of arterial compliance and autonomic function," said Dr. K. Spierer, from Coler Goldwater Specialty Hospital and Nursing Facility, Roosevelt Island, New York.

He and his colleagues examined the quantitative effects of aerobic fitness on arterial compliance and autonomic nervous system function in 28 HIV-positive, asymptomatic, and 20 HIV-negative subjects matched for age, BMI, maximum oxygen uptake (VO2max), and medication.

About half of the subjects in each group performed 45 minutes of moderate aerobic exercises (up to 75% of VO2max) three times per week for 10 weeks. The balance of the subjects in each group followed their normal daily activities.

As expected, the HIV-positive exercisers had higher VO2max and improved arterial compliance and autonomic function compared with the HIV-positive sedentary group.

"But what was really surprising," Dr. Spierer said, "was that for the variables of arterial compliance and the sensitivity of the baroreflex, which really hones in on blood pressure regulation, we found that the HIV-positive group who exercised did better than the HIV-negative group who did not."

What was "most striking" was that VO2max in the HIV-positive exercisers was equivalent to that of the HIV-negative exercisers, the researchers note.

HIV-positive patients often have reduced exercise capacity, muscle wasting, and respiratory complications, Dr. Spierer explained. However, this wasn't the case in the aerobically fit HIV-positive subjects in this study. Their exercise capacity was not significantly different from the fit HIV-negative subjects, he said.

These findings suggest that physical activity "may provide a protective effect on cardiovascular and autonomic variables and may be a cost-effective, adjunctive therapy in HIV-positive patients," the researcher speculate.

"What we really need are specific guidelines on exercise for patients with HIV because there are none that exist to date," Dr. Spierer said.