Ventilatory response to exercise in men and women 55 to 86 years of age

This study examines the relationship between minute ventilation (VE) and carbon dioxide production (VCO2) during exercise in men (n = 128) and women (n = 96), 55 to 86 yr of age. The means for the slopes of VE-VCO2 (delta VE/delta VCO2), examined for graded exercise below the ventilation threshold (TVE), increased significantly for men (p < 0.0001), from 25.0 +/- 0.7 (SEM) at mean age 58 (55 to 59) yr to 32.2 +/- 1.8 at mean age 83 (80 to 86) yr, but did not change for women (p = 0.0812), from 22.3 +/- 0.9 at mean age 58 (56-59) yr to 24.2 +/- 2.4 at mean age 79 (75 to 85) yr. A correlation that was significantly greater than zero was found between delta VE/delta VCO2 and age. The increase in delta VE/delta VCO2 was 0.29/yr for men (r = 0.47, p < 0.001) and 0.20/yr for women (r = 0.28, p = 0.0051). In both cases, the explained variance was small (men = 22%; women = 8%). VE, tidal volume (VT), and breathing frequency (fb) were examined at VCO2 = 1.0 L/min, the highest intensity that most older men and women could exercise without exceeding TVE. VE was significantly higher by 14% in men 80 to 86 yr of age (38.2 +/- 1.4 L/min) compared with men 55 to 59 yr of age (33.5 +/- 0.8), whereas there were no differences in VE for the women.(ABSTRACT TRUNCATED AT 250 WORDS)