Normal cardiopulrponary responses during incremental exercise in 20- to 70-yr-old men

Healthy men (N = 1424, age 20-70 yr) underwent a progressive incremental treadmill exercise test to volitional maximum. Cardiopulmonary variables were measured breathby-brcath. The aerobic power (VO_2max) declined at an average yearly rate of 0.33 ml•kg•^-1min^-1, HRmax declined 0.685 beats•min^-1yr^-1, and max O₂ pulse declined at an annual rate of 0.115 ml•beat^-1•kg^-1* 100. Gas exchange threshold (GET) expressed as percentage of VO_2max was 58% and 69% in the youngest (20-30 yr) and oldest (61-70 yr) decades, respectively. The average decline in V_E, Vt, f, and PETCO₂ over the entire age range was 29%, 10%, 21%, and 7%, respectively. There were increases in V_E/VO₂, and V_E/V_ECO₂, from age 20-70 yr of 13% and 14%, respectively, but no changes across 5 decades in PETO₂. Physical (height and weight) as well as life-style characteristics (leisure time activity, place of residency, smoking), were found to be potent predictors in most of the cardiopulmonary values at maximal exercise and therefore should be incorporated in the predictive equations for such variables. Normal response patterns of most cardiopulmonary variables throughout the range of exercise intensities were shown to be age-affected and thus should be standardized for age decades.