The effect of aging on submaximal exercise performance and recovery.

The upward drift of gas exchange variables during 70% maximal exercise and recovery half-times in aged and young subjects of equivalent age-predicted aerobic capacity was measured. In the aged subjects, upward drift of VE, VO2, and HR was reduced compared with the young group. The recovery of VE, VCO2, and VO2 was slowed in the aged.

Recovery of gas exchange variables and heart rate after maximal exercise in COPD.

Studies of the limited exercise capacity in patients with COPD have not assessed the recovery phase, although the phenomenon of increased oxygen uptake after exercise has been thoroughly investigated in normal subjects. Therefore, we compared the recovery of gas exchange variables and HR after maximal cycle ergometry in 16 patients with varying severities of airflow obstruction and ten aged control subjects. Aerobic capacity was reduced in the patients with COPD, and the rates of recovery of VE, VO2, VCO2, excess VCO2, and HR were all significantly slower in the patients with COPD than in the controls.