Perini R, S Milesi, NM Fisher, DR Pendergast,
A Veicsteinas. Heart Rate Variability during Dynamic Exercise
in Elderly Males and Females. Eur J Appl Physiol 82(1-2):8-15,
It has been proposed that cardiac control is altered in the elderly.
Power spectral analysis of heart rate variability (HRV) was performed
on 12 male and 11 female elderly subjects (mean age 74 years) while
at rest in supine and sitting positions, and at steady states during
5 min of exercise (35-95% peak oxygen consumption, VO2peak). There
were no differences in power, measured as a percentage of the total
of the high frequency peak (HF, centred at about 0.25 Hz; 13% in
males vs 12% in females), low frequency peak (LF, centred at 0.09
Hz; 25% in males and 22% in females), and very low frequency component
(VLF, at 0.03 Hz; 66% in males and 69% in females) between body
positions at rest. There was no difference in spectral power between
male and female subjects. Total power decreased as a function of
oxygen consumption during exercise, LF% did not change up to about
14 ml x kg(-1) x min(-1) (40% and 80% VO2peak in males and females,
respectively), then decreased towards minimal values in both genders.
HF% power and central frequency increased linearly with metabolic
demand, reaching higher values in male subjects than in female subjects
at VO2peak, while VLF% remained unchanged. Thus, the power spectra
components of HRV did not reflect the changes in autonomic activity
that occur at increasing exercise intensities, confirming previous
findings in young subjects, and indicated similar responses in both
R, NM Fisher, A Veicsteinas, DR Pendergast. Aerobic
Training and Cardiovascular Responses at Rest and during Exercise
in Older Men and Women. Med Sci Sports Exerc 34:700-708,
DR, NM Fisher and E Calkins. Cardiovascular, neuromuscular,
and metabolic alterations with age leading to frailty .
J Gerontol: Biol Sci 48(Special Issue):61-67, 1993.
NM, DR Pendergast. Improved cardiac output after exercise
in the head-down tilt position in elderly subjects. Gerontologist
39 Special Issue I:466, 1999.
NM, DR Pendergast and E Calkins. Maximal Isometric Torque
of Knee Extension as a Function of Muscle Length in Subjects of Advancing
age. Arch Phys Med Rehabil 71(10):729-734, 1990.
NM, DR Pendergast and E Calkins. Muscle Rehabilitation in
Impaired Elderly Nursing Home Residents. Arch Phys Med
Rehabil 72(3):181-185, 1991.
DR, E Calkins, NM Fisher and R Vickers. Muscle Rehabilitation
in Nursing Home Residents with Cognitive Impairment: a Pilot Study.
Am J Alzheimer Care Rel Dis July/August:: 20-25, 1987.
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