| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1Medical College of Wisconsin and Veterans Affairs Medical Center, Milwaukee, Wisconsin 53295; and 2University of Western Ontario, London, Ontario, Canada N6A 3K7
Submitted 25 July 2003 ; accepted in final form 4 February 2004
Nine healthy volunteers performed a series of single handgrip isometric contractions to test the hypothesis that the blood flow response to a contraction is determined solely by the tension-time index (isometric analog of work). Contractions were performed in duplicate at 15, 30, and 60% of maximal voluntary contraction (MVC) at durations of 0.5, 1, and 2 s. Forearm blood flow (FBF) was measured beat by beat by using Doppler ultrasound. Peak FBF responded in a graded fashion to graded increases in peak tension with contraction time held constant (35, 56, and 90 ml/min for 15, 30, and 60% MVC for 1 s, respectively). When tension was kept constant, peak FBF responded in a graded fashion to graded increases in duration (77, 90, and 97 ml/min for 60% MVC for 0.5, 1, and 2 s). With a constant tension-time index, peak FBF responded in a graded fashion to graded increases in peak tension (48, 56, and 77 ml/min for 15% MVC/2 s, 30% MVC/1 s, and 60% MVC/0.5 s). Similar trends were also observed for total postcontraction hyperemia. Blood flow increased regardless of whether the change in tension-time index was accomplished by an increase in tension or duration of contraction. However, with a constant tension-time index, the change in blood flow was related to the peak tension developed. Our results suggest that the blood flow response to a single muscle contraction is not determined solely by the work performed (tension-time index) but also by the number of muscle fibers recruited.
exercise; tension-time index; hyperemia; skeletal muscle; human
This article has been cited by other articles:
|
|
 |
|
  J. U. Gonzales, B. C. Thompson, J. R. Thistlethwaite, A. J. Harper, and B. W. Scheuermann Forearm blood flow follows work rate during submaximal dynamic forearm exercise independent of sex J Appl Physiol, December 1, 2007; 103(6): 1950 - 1957. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. S. Clifford Skeletal muscle vasodilatation at the onset of exercise J. Physiol., September 15, 2007; 583(3): 825 - 833. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. P. Dufour, S. Doutreleau, E. Lonsdorfer-Wolf, E. Lampert, C. Hirth, F. Piquard, J. Lonsdorfer, B. Geny, B. Mettauer, and R. Richard Deciphering the metabolic and mechanical contributions to the exercise-induced circulatory response: insights from eccentric cycling Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2007; 292(4): R1641 - R1648. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Armstrong, A. K. Dua, and C. L. Murrant Time course of vasodilation at the onset of repetitive skeletal muscle contractions Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2007; 292(1): R505 - R515. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. S. Clifford, H. A. Kluess, J. J. Hamann, J. B. Buckwalter, and J. L. Jasperse Mechanical compression elicits vasodilatation in rat skeletal muscle feed arteries J. Physiol., April 15, 2006; 572(2): 561 - 567. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Sostaric, t. l. S. L. Skinner, M. J. Brown, T. Sangkabutra, I. Medved, T. Medley, S. E. Selig, I. Fairweather, D. Rutar, and M. J. McKenna Alkalosis increases muscle K+ release, but lowers plasma [K+] and delays fatigue during dynamic forearm exercise J. Physiol., January 1, 2006; 570(1): 185 - 205. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. W. G. E. VanTeeffelen and S. S. Segal Rapid dilation of arterioles with single contraction of hamster skeletal muscle Am J Physiol Heart Circ Physiol, January 1, 2006; 290(1): H119 - H127. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. S. Kirby, R. R. Markwald, E. G. Smith, and F. A. Dinenno Mechanical effects of muscle contraction do not blunt sympathetic vasoconstriction in humans Am J Physiol Heart Circ Physiol, October 1, 2005; 289(4): H1610 - H1617. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. F Ferreira, A. J Harper, D. K Townsend, B. J Lutjemeier, and T. J Barstow Kinetics of estimated human muscle capillary blood flow during recovery from exercise Exp Physiol, September 1, 2005; 90(5): 715 - 726. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. L. Murrant Stimulation characteristics that determine arteriolar dilation in skeletal muscle Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2005; 289(2): R505 - R513. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. W. Wray, A. J Donato, A. Uberoi, J. P Merlone, and R. S Richardson Onset exercise hyperaemia in humans: partitioning the contributors J. Physiol., June 15, 2005; 565(3): 1053 - 1060. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. J. Hamann, H. A. Kluess, J. B. Buckwalter, and P. S. Clifford Blood flow response to muscle contractions is more closely related to metabolic rate than contractile work J Appl Physiol, June 1, 2005; 98(6): 2096 - 2100. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. R. Saunders and M. E. Tschakovsky Evidence for a rapid vasodilatory contribution to immediate hyperemia in rest-to-mild and mild-to-moderate forearm exercise transitions in humans J Appl Physiol, September 1, 2004; 97(3): 1143 - 1151. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
