Marathon training is safe for people with HIV

Marathon run training is safe for people with HIV, investigators from Germany report in BMC Infectious Diseases. Training also had a number of beneficial effects, including a significant increase in CD4 cell count and improvements in cholesterol and blood pressure, though the investigators note these were already normal at baseline.

“The main finding of our study was that regular aerobic activity resulting in performing a marathon was safe for people living with HIV. We could not show any potential harm, or increase in infections such as URTIs [upper respiratory tract infections],” write the authors. “Withdrawals from the study did not occur due to major health issues. There were no unfavourable effects on immunology and virological parameters.”

Little is known about the effects of sporting activities on the health and wellbeing of people with HIV. Studies involving people in the general population have shown that regular endurance training can be associated with short-term minor immune suppression and increased frequency of colds and coughs but also long-term boosts in immune function.

To establish a clearer understanding of the impact of a programme of regular moderate aerobic endurance training on the health of people with HIV, investigators in Bonn designed a prospective study monitoring individuals training for a marathon – a 42km (26.2 mile) run.

Sports scientists designed individualised training programmes lasting 12 months. Participants trained three to four times a week. Training consisted of 3-4 hours of running at the start of the study, increasing to 7-10 hours per week. At the start of the study, participants trained at 60-70% of their maximum heart rate, increasing to 70-80%. 

A total of 21 people were recruited. Baseline assessments included CD4 cell count and viral load, weight, blood pressure, lipids, and kidney and liver function. Participants also completed a quality of life questionnaire. All these assessments were repeated three and six months into the training programme and again on the night before the marathon.

A total of eight people (38%) dropped out but for reasons unrelated to the safety of exercise.

Analysis was restricted to the 13 individuals who completed the training programme and marathon (VIII Gay Games, Cologne, 2010). Median age was 42 years (27-50 years), 12 of the participants were male and one was female. Eleven people were taking antiretroviral therapy, nine of whom had an undetectable viral load. Median CD4 cell count at baseline was 640 cells/mm³. Blood pressure, lipid profile, and liver and kidney function were all normal. Three people had a history of AIDS-defining illnesses, and there were five significant current co-morbidities, including two cases of chronic hepatitis, two cases of depression and one case of dermal psoriasis. Self-reported quality of life was good.

At the end of the training programme, median CD4 cell count had increased significantly to 745 cells/mm³ (p = 0.001). This was accompanied by a significant fall in CD4-T cell apoptosis (53% at baseline to 32% at end of the study, p < 0.01). Training had no effect on viral load. Significant improvements were observed in total cholesterol (median 185 mg/dl vs 167 mg/dl; 4.78 vs 4.31 mmol/L; p = 0.02) and systolic blood pressure (median 125mmHg vs 120mmHg; p = 0.001). Liver and kidney function remained normal and there was no change in reported quality of life. There was no spike in the frequency of upper respiratory tract infections during the training period, including during the winter months.

The immunological benefits of training became significant at the six-month follow-up point. “Our data support a beneficial effect on the CD4 cell count,” comment the authors. “But our study design and number of participants do not allow quantifying the direct effect of exercise on the lymphocytes and the underlying mechanisms.”

The authors recognise that their study has several limitations: lack of complete cardiovascular parameters; lack of data on individual training intensities; small sample size; no control group; and high drop out rate.

Moreover, they were unable to determine whether beneficial effects in terms of immune function were directly due to training or antiretroviral therapy.

“HIV-infected persons can perform moderate endurance training. No safety issues were found in this ‘healthy’ study population. These data pushed the safety limit of exercise in a specific group of people living with HIV/AIDS to the distance of a marathon run,” conclude the authors. “In a long-term perspective effects of endurance training on typical HIV-associated risks such as cardiovascular diseases would be desirable.”