Faculty Collaboration Database

Active hyperemia and vascular conductance differ between men and women for an isometric fatiguing contraction. J Appl Physiol (1985) 2006 Jul;101(1):140-50

Date

04/08/2006

Pubmed ID

16601303

DOI

10.1152/japplphysiol.01567.2005

Scopus ID

2-s2.0-33745872535 (requires institutional sign-in at Scopus site)   65 Citations

Abstract

To understand the role of muscle perfusion in the sex differences of muscle fatigue, we compared the time to task failure, postcontraction (active) hyperemia, and vascular conductance for an isometric fatiguing contraction performed by young men and women with the handgrip muscles at 20% of maximal voluntary contraction (MVC) force. In study 1, the men (n = 16) were stronger than the women (n = 18), and study 2, the men (n = 7) and women (n = 7) were matched for strength. Isometric contractions were sustained during two sessions: 1) until the target force could no longer be achieved or 2) for 4 min. For both studies, blood flow and vascular conductance were similar for the men and women at rest and after 10 min of occlusion, and at task failure for the fatiguing contraction estimated using forearm venous occlusion plethysmography. In study 1, the time to task failure was longer for the women (11.4 +/- 2.8 min) than for the men (8.4 +/- 2.4 min; P = 0.003). However, at the end of the 4-min contraction, active hyperemia and vascular conductance were greater for the men than the women (99 vs. 70% peak blood flow; P < 0.001). In study 2, the men and women had similar strength and a similar time to failure (8.4 +/- 1.6 vs. 8.6 +/- 2.3 min). Active hyperemia was greater for the men than the women (86 vs. 64% peak flow; P = 0.038) after the 4-min contraction, as was vascular conductance (80 vs. 57% peak conductance; P = 0.02). Thus the briefer time to failure of men than women for an isometric fatiguing contraction is a function of the greater strength of men but is not dependent on differences in the active hyperemia and vascular conductance.

Author List

Hunter SK, Schletty JM, Schlachter KM, Griffith EE, Polichnowski AJ, Ng AV

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

Adult
Blood Pressure
Electromyography
Female
Forearm
Hand Strength
Heart Rate
Humans
Hyperemia
Isometric Contraction
Male
Muscle Fatigue
Muscle, Skeletal
Physical Endurance
Physical Exertion
Plethysmography
Regional Blood Flow
Sex Characteristics
Task Performance and Analysis
Time Factors