Autonomic responses to exercise and cold pressor test in young healthy Hispanic adults.

Abstract

Hispanic/Latino (H/La) individuals have a notably high incidence of type 2 diabetes and obesity, significantly increasing their cardiovascular risk. Although regular exercise reduces the risk of cardiovascular diseases, abnormal hemodynamic responses during exercise can increase the risk of adverse events during/immediately following the exercise bout. To date, no studies have investigated the pressor response to exercise in the H/La population. Therefore, we examined exercise pressor reflex in 48 young healthy adults [22 H/La, 26 non-Hispanic White (NHW)]. Beat-to-beat blood pressure (finger plethysmography) and heart rate (ECG) were measured before and during isometric handgrip (HG) performed at 30% and 40% of their maximal voluntary contraction, followed by postexercise ischemia (PEI) to isolate the muscle metaboreflex. In addition, cold pressor test (CPT) was used to quantify pressor response to a nonexercise sympathoexcitatory stimulus. We observed that increases in mean arterial pressure (ΔMAP) during 30%HG (P = 0.58) and its subsequent PEI (P = 0.93) were not different between the two groups. Likewise, ΔMAP during 40%HG and PEI was similar between both groups (PEI: H/La = 39 ± 8 mmHg, NHW = 37 ± 11 mmHg; P = 0.51). However, the pressor response to CPT was significantly augmented in H/La (ΔMAP: H/La = 31 ± 11 mmHg, NHW = 22 ± 11 mmHg; P = 0.02). Together, these data suggest that the exercise pressor reflex and muscle metaboreflex are not altered in young healthy H/La adults. However, H/La adults exhibit elevated blood pressure reactivity to a nonexercise sympathoexcitatory stimulus, which may be indicative of early autonomic dysregulation in Hispanic adults as compared with NHW adults, potentially contributing to higher cardiovascular risk with aging in the Hispanic population.NEW & NOTEWORTHY This is the first study to investigate exercise-induced cardiovascular responses in young, healthy Hispanic individuals. We found that although the exercise pressor reflex and the muscle metaboreflex are not augmented in Hispanic adults, they exhibit elevated blood pressure reactivity in response to the cold pressor test. This remarkably high pressor response to a nonexercise stimulus potentially predisposes the Hispanic adults to earlier development of future hypertension.