Aerobic fitness in a population of independently living men and women aged55-86 years

Purpose: The purpose was to examine, for a subset of a large random survey of men and women, the age-related changes in the parameters of aerobic func tion, maximal oxygen consumption ((V)over dotO(2max)), and ventilatory thre shold ((T)over dot(VE)). Methods: A "ramp-like" treadmill protocol was desi gned to measure (V)over dotO(2max) and (T)over dot(VE) on a total of 298 su bjects (152 men and 146 women), aged 55-86 yr. Results: Data for VO2max (an d HRmax) and (T)over dot(VE), by 5-yr age groups provide "normative" result s. Age-related declines in (V)over dotO(2max) and (T)over dot(VE) were fit by a linear model; however, age explained at most 37% of the variance acros s ages 55-86 yr. In this restricted age range, the rate of decline in (V)ov er dotO(2max) in both men (-0.034 L.min(-1).yr(-1)) and women (-0.019 L.min (-1).yr(-1)), was similar to that of previous reports for linear regression with age. Men, but not women, showed a decrease in body mass across age. T hus, the decline in (V)over dotO(2max) expressed relative to body mass was similar in men (0.31 mL.kg(-1).min(-1).yr(-1)) and women (0.25); however, a cross this older age the decline is slower than noted for younger groups. T he minimum level of aerobic power compatible with an independent life at ag e 85 yr was approximately 18 mL.kg(-1).min(-1) in men and 15 mL.kg(-1).min( -1) in women. Regression analysis showed HRmax across this age span is not well predicted by age. (T)over dot(VE) across age declined at about one-hal f the rate of the (V)over dotO(2max), and in older age was approximately 85 % of the (V)over dot not equivalent to O-2max. Conclusion: The study provid es "normative" cardiorespiratory function data of a random sample of indepe ndently living men and women aged 55-86 yr.