Influence of age on physical performance, heart rate and systolic blood pressure response during exercise in apparently healthy women.

In order to assess normal physical performance in women, a near-maximal ergometer bicycle test was performed in 95 healthy non-athletic women aged 24-65 years (mean 44 years). The starting load was 50 W and the load was increased by 50 W every 4 min until exhaustion. Physical performance was expressed as cumulative work in Watts (W). All subjects had normal two-dimensional, M-Mode and Doppler echocardiographic findings. Physical performance was similar in the age groups 24-29, 30-39 and 40-49 years. Mean cumulative work among subjects less than 50 years was 1208 (600-1800) W vs. 947 (500-1600) W (p less than 0.001) in those greater than or equal to 50 years. Physical performance was similar in the age groups 50-59 and 60-65 years (NS). An inverse correlation between maximal heart rate and age was found (r = 0.64, p less than 0.001). Systolic blood pressure increased more during exercise in the subjects greater than or equal to 50 years (p less than 0.001 vs. those aged less than 50 years). M-Mode echocardiographic measurements at rest were similar in all age groups. These findings may be related to reduction in beta-sympathetic stimulation during exercise in women greater than or equal to 50 years of age.