Faculty Collaboration Database

Endurance exercise training is associated with elevated basal sympathetic nerve activity in healthy older humans. J Appl Physiol (1985) 1994 Sep;77(3):1366-74

Date

09/01/1994

Pubmed ID

7836141

DOI

10.1152/jappl.1994.77.3.1366

Scopus ID

2-s2.0-0028088120 (requires institutional sign-in at Scopus site)   79 Citations

Abstract

We tested the hypothesis that endurance training is associated with altered basal levels of muscle sympathetic nerve activity (MSNA) and responses to acute stress in healthy older adults. MSNA (peroneal microneurography) and plasma norepinephrine (NE) concentrations were measured during supine rest, a cold pressor test, and isometric handgrip (40% maximal voluntary force to exhaustion) in 16 older masters endurance athletes [10 men, 6 women; 66 +/- 1 (SE) yr] and 15 healthy normotensive untrained control subjects (9 men, 6 women; 65 +/- 1 yr). The athletes had higher levels of estimated daily energy expenditure and maximal oxygen uptake and lower levels of resting heart rate and body fat than the control subjects (all P < 0.05). MSNA during supine rest was elevated in the athletes whether expressed as burst frequency (43 +/- 2 vs. 32 +/- 3 bursts/min, respectively; P < 0.05) or burst incidence (75 +/- 4 vs. 52 +/- 5 bursts/100 heartbeats, respectively; P < 0.01). These whole group differences were due primarily to markedly higher levels of MSNA in the athletic vs. untrained women (48 +/- 4 vs. 25 +/- 3 bursts/min, 82 +/- 3 vs. 38 +/- 3 bursts/100 heartbeats, respectively, P < 0.001). In contrast, basal plasma NE concentrations were not significantly different in the athletes vs. control subjects. The MSNA and plasma NE responses to acute stress tended to be greater in the athletes. These findings indicate that vigorous regular aerobic exercise is associated with an elevated level of MSNA at rest and a tendency for an enhanced response to acute stress in healthy normotensive older humans.

Author List

Ng AV, Callister R, Johnson DG, Seals DR

Author

Alexander V. Ng PhD Associate Professor in the Exercise Science department at Marquette University

MESH terms used to index this publication - Major topics in bold

Aged
Aging
Autonomic Fibers, Postganglionic
Blood Pressure
Female
Heart Rate
Humans
Isometric Contraction
Male
Middle Aged
Muscle, Skeletal
Norepinephrine
Physical Endurance
Physical Exertion
Skinfold Thickness
Stress, Physiological
Supine Position
Sympathetic Nervous System