Perini 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, 2002.
PURPOSE: The effects of an intense 8-wk aerobic
training program on cardiovascular responses at rest and during
exercise, including heart rate variability (HRV) as an expression
of autonomic modulation, were evaluated in subjects over 70 yr (mean:
73.9 +/- 3.5 yr). METHODS: Before and after training
in 7 men and 8 women: a) heart rate (HR), blood pressures (BPs),
pulse pressure (PP), and oxygen uptake were measured at rest, during,
and after exhausting incremental exercise; b) HRV power spectra
were calculated at rest in supine and sitting, and during and after
two submaximal constant loads (5 min). Power in low-frequency (LF,
0.04-0.15 Hz) and high-frequency (HF, >0.15 Hz) bands were expressed
as a percent of total power minus power < 0.04 Hz. RESULTS:
After training: a) at rest HR and HRV parameters (in both body positions)
were unchanged, whereas BPs decreased; b) peak cycle resistance
and oxygen consumption increased by 25% and 18%, respectively, but
no change in maximal HR and BPs were found; c) during submaximal
loads HR was unchanged at the same metabolic demand, whereas SBP
and DBP were lower than before at low loads whereas PP was unchanged.
LF power decreased and HF increased at oxygen uptakes above about
0.7 L.min-1 similarly before and after training; and d) recovery
of all parameters was similar to pretraining and complete after
10 min CONCLUSIONS: The increase in exercise capacity
without changes in cardiovascular parameters suggests that 8 wk
of aerobic training augmented peripheral gas exchange but not delivery
to muscle. The lack of effect on HRV indicates that the improvements
in aerobic power and cardiac autonomic modulation, at least in subjects
over 70 yr, are dissociated. Moreover, the metabolic demand seems
to be the main factor for the changes in HRV power spectra that
occur during exercise.
OTHER ABSTRACTS
Pendergast
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.
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, 2000.
Fisher NM, DR Pendergast. Improved cardiac output after exercise
in the head-down tilt position in elderly subjects. Gerontologist
39 Special Issue I:466, 1999.
Fisher 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.
Fisher NM, DR Pendergast and E Calkins. Muscle Rehabilitation
in Impaired Elderly Nursing Home Residents. Arch Phys Med
Rehabil 72(3):181-185, 1991.
Pendergast 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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