Baroreflex responsiveness is maintained during isometric exercise in humans. J Appl Physiol (1985) 1986 Aug;61(2):797-803
Date
08/01/1986Pubmed ID
3745073DOI
10.1152/jappl.1986.61.2.797Scopus ID
2-s2.0-0022500214 (requires institutional sign-in at Scopus site) 49 CitationsAbstract
The simultaneous rise in heart rate and arterial pressure during isometric handgrip exercise suggests that arterial baroreflex control may be altered. We applied incremental intensities of neck suction and pressure to nine healthy young men to alter carotid sinus transmural pressure. Carotid stimuli were delivered during 1) supine control, 2) "anticipation" of beginning exercise, and 3) handgrip (20% of maximum voluntary contraction). Anticipation was a quiet period, immediately preceding the beginning of handgrip, when no muscular work was being performed. Compared with control, the R-R interval prolongation and mean arterial pressure decline provoked by carotid stimuli were decreased during the anticipation period. These data suggest that influences from higher central neural locations may alter baroreflex function. Furthermore, we derived stimulus-response curves relating carotid sinus transmural pressure to changes in R-R interval and mean arterial pressure. These curves were shifted during handgrip; however, calculated regression slopes were not changed from control. The data indicate that isometric handgrip exercise has a specific influence on human carotid baroreflex control of arterial pressure and heart period: baroreflex function curves are shifted rightward during handgrip, whereas baroreflex sensitivity is unchanged. Furthermore, central neural influences may be partially involved in these alterations.
Author List
Ebert TJAuthor
Thomas J. Ebert MD, PhD Adjunct Professor in the Anesthesiology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultBlood Pressure
Cues
Electrocardiography
Humans
Isometric Contraction
Male
Muscle Contraction
Neck
Physical Exertion
Pressoreceptors
Reflex
Suction
