Vol. 89, Issue 5, 1771-1777, November 2000
Initial ventilatory and circulatory responses to dynamic
exercise are slowed in the elderly
Koji
Ishida1,
Yasutake
Sato2,
Keisho
Katayama2, and
Miharu
Miyamura1
1 Laboratory for Exercise Physiology, Research Center of
Health, Physical Fitness and Sports, and 2 Graduate School of
Medicine, Nagoya University, Nagoya 464-8601, Japan
To elucidate the characteristics of
ventilatory and circulatory responses at the onset of brief and light
exercise in the elderly, 13 healthy, elderly men, aged 66.8 yr (mean),
exerted bilateral leg extension-flexion movements for only 20 s
with a weight around each ankle, with each weight being ~2.5% of
their body mass. Similar movements were passively performed on the
subjects by the experimenters. These results were compared with those
of 13 healthy, young men (22.9 yr). Minute ventilation increased at the
onset of voluntary exercise and passive movements in both groups but
showed a slower increase in the elderly. Heart rate also increased in
both groups but showed less change in the elderly. Mean blood pressure
temporarily decreased in both groups but less in the elderly. The
magnitude of relative change (gain) of heart rate in the elderly was
significantly smaller than that in the young, whereas the increasing
rate to reach one-half of the gain (response time) of ventilation in
the elderly was significantly slower than that in the young. Similar
tendencies were observed in the passive movements. It is concluded that
the elderly show slower ventilatory response and attenuated circulatory
response at the onset of dynamic voluntary exercise and passive movements.
aging; exercise onset; ventilation; heart rate; blood pressure
