Document Detail

Central command contributes to increased blood flow in the noncontracting muscle at the start of one-legged dynamic exercise in humans.
MedLine Citation:
PMID:  22500007     Owner:  NLM     Status:  MEDLINE    
Whether neurogenic vasodilatation contributes to exercise hyperemia is still controversial. Blood flow to noncontracting muscle, however, is chiefly regulated by a neural mechanism. Although vasodilatation in the nonexercising limb was shown at the onset of exercise, it was unclear whether central command or muscle mechanoreflex is responsible for the vasodilatation. To clarify this, using voluntary one-legged cycling with the right leg in humans, we measured the relative changes in concentrations of oxygenated-hemoglobin (Oxy-Hb) of the noncontracting vastus lateralis (VL) muscle with near-infrared spectroscopy as an index of tissue blood flow and femoral blood flow to the nonexercising leg. Oxy-Hb in the noncontracting VL and femoral blood flow increased (P < 0.05) at the start period of voluntary one-legged cycling without accompanying a rise in arterial blood pressure. In contrast, no increases in Oxy-Hb and femoral blood flow were detected at the start period of passive one-legged cycling, suggesting that muscle mechanoreflex cannot explain the initial vasodilatation of the noncontracting muscle during voluntary one-legged cycling. Motor imagery of the voluntary one-legged cycling increased Oxy-Hb of not only the right but also the left VL. Furthermore, an increase in Oxy-Hb of the contracting VL, which was observed at the start period of voluntary one-legged cycling, had the same time course and magnitude as the increase in Oxy-Hb of the noncontracting muscle. Thus it is concluded that the centrally induced vasodilator signal is equally transmitted to the bilateral VL muscles, not only during imagery of exercise but also at the start period of voluntary exercise in humans.
Kei Ishii; Nan Liang; Anna Oue; Ai Hirasawa; Kohei Sato; Tomoko Sadamoto; Kanji Matsukawa
Related Documents :
25204857 - Effects of exercise on bmi z-score in overweight and obese children and adolescents: a ...
14577577 - Nitric oxide and iron metabolism in exercised rat with l-arginine supplementation.
22344057 - Reliability of power output during eccentric sprint cycling.
16888797 - Mri detects myocardial iron in the human heart.
12477007 - Bilateral arm power imbalance in swim bench exercise to exhaustion.
16331127 - Voluntary training in mice and submandibular lymphocyte response to acute exercise.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2012-04-12
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  112     ISSN:  1522-1601     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  2012 Jun 
Date Detail:
Created Date:  2012-06-18     Completed Date:  2013-01-17     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1961-74     Citation Subset:  IM    
Department of Physiology, Graduate School of Health Sciences, Hiroshima University, Hiroshima, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Blood Pressure / physiology
Exercise / physiology*
Hemoglobins / metabolism
Leg / blood supply,  physiology*
Motor Neurons / metabolism,  physiology*
Muscle Contraction / physiology*
Muscle, Skeletal / blood supply*,  metabolism,  physiology*
Oxygen / metabolism
Regional Blood Flow / physiology
Spectroscopy, Near-Infrared / methods
Vasodilation / physiology
Young Adult
Reg. No./Substance:
0/Hemoglobins; 7782-44-7/Oxygen
Comment In:
J Appl Physiol (1985). 2012 Jun;112(12):1959-60   [PMID:  22582219 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Continuum vs. spring network models of airway-parenchymal interdependence.
Next Document:  Effect of incremental exercise on airway and systemic inflammation in patients with COPD.