Cardiovascular Responses to Different Resistance Exercise Protocols in Elderly.

Increase in muscle mass and strength through resistance exercise (RE) has been highly recommended for healthy aging. On the other hand, RE could lead to acute cardiovascular risks prompted mainly by intense blood pressure elevations and cardiac autonomic imbalance. We compared the cardiovascular responses to three different RE protocols performed by 21 healthy elderly on a leg press machine. The protocols tested were high load (80% 1RM) until muscular failure (HL); low load (30% 1RM) until muscular failure (LL); low load, 30 repetitions followed by 3 sets of 15 repetitions, with 50% blood flow restriction (LL-BFR); and a control session (CON). Based on heart rate variability analysis, only LL kept parasympathetic indexes lower than CON at 30 min recovery. By finger photoplethysmography, LL-BFR prompted higher systolic and mainly diastolic blood pressure increments in many sets. The heart rate and cardiac output increase, and total peripheral resistance reduction following exercise were not different among RE protocols. There was no significant post-exercise hypotension and carotid arterial compliance changes. HL seems to be the safer protocol to be recommended for the healthy elderly, because it induces lower blood pressure increments and faster parasympathetic recovery compared to LL and LL-BFR.