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Cardiovascular responses to external compression of human calf muscle vary during graded metaboreflex stimulation
Author(s) -
Bell Martin P. D.,
White Michael J.
Publication year - 2005
Publication title -
experimental physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.925
H-Index - 101
eISSN - 1469-445X
pISSN - 0958-0670
DOI - 10.1113/expphysiol.2004.029140
Subject(s) - isometric exercise , cuff , medicine , cardiology , circulatory system , ankle , intensity (physics) , thigh , electrical muscle stimulation , stimulation , anatomy , anesthesia , surgery , physics , quantum mechanics
This study investigated the cardiovascular response to a standard external muscle compression during concomitant muscle metaboreflex stimulation of varying intensity in human calf muscle. Eleven healthy male subjects (mean ( s.d. ) age, 26 (5.6) years; height, 177 (5) cm; weight, 74.3 (6.8) kg) were seated in an isometric dynamometer with the angle of the knee at 90 deg, and the angle of the ankle at 85 deg. After a 150‐s rest period, subjects were asked to either perform isometric plantar flexion at 20, 30, 40, 50, 60, 70 or 80% of previously determined maximum isometric contractile force (MVC) for 90 s, or to sit at rest for this period. A thigh cuff maintained circulatory occlusion throughout the exercise period and for 180 s post exercise. After 60 s of post‐exercise circulatory occlusion (PECO), a calf cuff was inflated to 300 mmHg for 60 s followed by a further 60 s of PECO alone after which the thigh cuff was deflated. During PECO the mean arterial pressure (MAP) increase from rest was dependent upon the preceding exercise intensity ( P < 0.001). Compression elicited a further significant change in MAP, and the magnitude of this change from the PECO baseline was also dependent upon the preceding exercise intensity ( P < 0.01). These results are compatible with activation of a metabolically sensitised population of mechanoreceptive afferents in human muscle during external compression.