Cardiovascular Responses to Exercise in People Living With HIV/AIDS: Effects of Exercise Training

Autonomic and Hemodynamic Responses to Muscular Ergoreflex Activation in People Living With HIV/AIDS: Effects of Exercise Training.

Patients living with HIV (PLWHIV) have compromised muscle metaboreflex, which can cause exercise intolerance. This randomized controlled clinical trial will verify the effects of regular exercise on autonomic and hemodynamic responses to muscle ergoreflex activation in these patients. PLWHIV without regular physical exercise will be randomly assigned into an exercise training or a control group. The exercise training group will undergo regular physical exercise during 12 weeks (60-min session performed 3 times/wk with moderate intensity), while the control group will keep inactive. Another group consisted of inactive HIV-uninfected group will be included. The primary endpoints will be blood pressure and autonomic markers in response to the Stroop Color-Word Test and the activation of muscle ergoreflex, by means of the post-exercise circulatory arrest (PECA), which will be performed with and without the topical application of a capsaicin-based analgesic balm. Secondary endpoints will include heart rate, peripheral vascular resistance, stroke volume, cardiac output, blood lactate concentration, anthropometrics, and handgrip strength. The active and inactive PLWHIV groups will be evaluated before and after the exercise training, while the healthy group only at baseline.

HIV-infection is associated to a reduced maximal cardiac output and blunted pressor reflex response to static handgrip exercise, which are suggestive of impaired ergoreflex activation. An abnormal ergoreflex activation may lead to exercise intolerance and increases in cardiovascular risk. Despite the importance of therapeutic strategies in reducing the cardiovascular risk among patients living with HIV, exercise-related effects on ergoreflex sensitivity in these population have not been previously investigated.

Inclusion Criteria for people living with HIV:

• diagnosis of HIv infection for at least 5 years;
• use of combined antiretroviral therapy for at least 3 years;
• asymptomatic and free from opportunistic diseases at enrollment.

Exclusion Criteria:

• regular physical exercise;
• malnutrition;
• presence of coronary artery disease, ischemic diseases, pulmonary disease, diabetes, Chagas disease, tuberculosis, heart failure, hypertension;
• using pacemakers and/or antidepressant, antiarrhythmic or antihypertensive medication, especially beta-blockers.