Abstract
We investigated the muscle metaboreflex contribution to blood pressure response during
dynamic handgrip exercise in men living with HIV (MLHIV) vs. without HIV (Controls).
Pressor and heart rate responses were evaluated during metaboreflex activation through
post-exercise muscle ischemia (PEMI) method and control exercise session (CER) in
17 MLHIV and 21 Controls. Protocols were performed randomly on the same day, being
both sessions composed of 12 min, as follows: a) 3 min at rest, b) 3 min of dynamic
handgrip exercise at 30% of maximal voluntary contraction, c) 3 min of recovery post-exercise
with vascular occlusion (occlusion only in PEMI), and d) 3 min of recovery post-exercise
without vascular occlusion. To assess metaboreflex response, differences between PEMI
and CER in recovery post-exercise were calculated for blood pressure and heart rate.
Systolic and mean blood pressure (P<0.01) were superior in the last 2 min of recovery
with vascular occlusion at PEMI in relation to CER for both groups. No difference
was found between groups for blood pressure and heart rate (P>0.05). However, metaboreflex
response for systolic blood pressure was lower in MLHIV vs. Controls (4.05±4.63 vs.
7.61±3.99 mmHg; P=0.01). In conclusion, pressor response during metaboreceptor stimulation
was attenuated in men living with HIV, which may suggest loss of muscle metaboreflex
sensibility.
Key words
exercise - ergoreflex - exercise pressor reflex - HIV infection
