The purpose of this study was to investigate the cardiovascular responses during isotonic concentric (CON) and eccentric (ECC) knee extension exercise in older adults. Peak torque for CON knee extension was determined in healthy older females (n=8). Subjects then performed isotonic CON and ECC knee extension exercise at 50% and 70% of CON peak torque. Heart rate (HR) and blood pressure (BP) were measured continuously, and mean arterial blood pressure (MAP) and rate-pressure product (RPP) were calculated. CON exercise elicited greater changes in systolic blood pressure(SBP),diastolic blood pressure(DBP),MAP and RPP than ECC exercise at 50% of CON peak torque (p<0.05). CON exercise elicited greater changes in SBP,DBP and MAP than ECC exercise at 70% of CON peak torque (p<0.05). Isotonic CON knee extension exercise elicited significantly greater increases in cardiovascular stress than ECC exercise at both 50% and 70% of CON peak torque. This result is relevant to resistance exercise in older people.
