Cardiovascular function in the elderly during water immersion.
In attempting to clarify the effects of aging on the regulatory functions of the cardiovascular system, we measured blood pressure, heart rate and stroke volume during thermoneutral head-out water immersion in seven healthy elderly and eight healthy young subjects. In the young subjects water immersion resulted in a marked increase in stroke volume, a deceleration of the heart rate and stable blood pressure values. In the elderly group the blood pressure increased significantly during shoulder-level water immersion. Compared to the young subjects, the elderly presented a less pronounced elevation of the stroke volume, and no change in the heart rate. These results indicate that the vasodepressive mechanisms regulated by baroreflexes diminish with aging, resulting in an elevation of blood pressure.
Sugiyama
Y
Y
Department of Autonomic & Behavioral Neurosciences, Division of Higher Nervous Control, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan.
Miwa
C
C
Xue
Y X
YX
Iwase
S
S
Suzuki
H
H
Matsukawa
T
T
Watanabe
T
T
Kobayashi
F
F
Mano
T
T
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D018495:Fluid Shifts / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007101:Immersion / Q000503:physiopathology*; D008297:Male; D013318:Stroke Volume / Q000502:physiology*; D014867:Water; D018474:Weightlessness Simulation
D014867:Water