| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Medicine, University of California, San Diego, La Jolla, CA, USA
2 Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
3 Department of Medicine, University of California, San Diego, La Jolla, CA, USA; Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
* To whom correspondence should be addressed. E-mail: rrichardson{at}ucsd.edu.
The interactions between exercise, vascular and metabolic plasticity, and aging have provided insight into the prevention and restoration of declining whole body and small muscle mass exercise performance known to occur with age. Metabolic and vascular adaptations to normoxic knee-extensor exercise training (1 hour 3 times a week for 8 weeks) were compared between six sedentary young (20 ±1 yrs, Y) and six sedentary old (67 ± 2 yrs, O) subjects. Arterial and venous blood samples, in conjunction with a thermodilution technique facilitated the measurement of quadriceps muscle blood flow and hematologic variables during incremental knee-extensor exercise. Pre-training, young and old subjects attained a similar maximal work rate (WRmax) (Y=27±3, O=24±4 W) and similar maximal quadriceps oxygen consumption (Muscle VO2max) (Y=0.52 ± 0.03, O=0.42 ± 0.05 l/min), which increased equally in both groups post training (WRmax, Y=38±1, O=36±4 W, Muscle VO2max, Y=0.71 ± 0.1, O=0.63 ± 0.1 l/min). Pre training, muscle blood flow was ~500ml lower in the old when compared to the young throughout incremental knee-extensor exercise. Following eight weeks of knee-extensor exercise training, the young reduced muscle blood flow ~700 ml/min, elevated a-v O2 difference ~1.3 ml/dl, and increased LVR ~17 mmHg/ml/min, whereas the old subjects revealed no training induced changes in these variables. Together, these findings indicate that following eight weeks of small muscle mass exercise training, young and old subjects of equal initial metabolic capacity have a similar ability to increase quadriceps muscle WRmax and muscle VO2max despite an attenuated vascular and/or metabolic adaptation to submaximal exercise in the old.
This article has been cited by other articles:
|
|
 |
|
  B. A. Parker, S. L. Smithmyer, J. A. Pelberg, A. D. Mishkin, and D. N. Proctor Sex-specific influence of aging on exercising leg blood flow J Appl Physiol, March 1, 2008; 104(3): 655 - 664. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. G. Schrage, J. H. Eisenach, and M. J. Joyner Ageing reduces nitric-oxide- and prostaglandin-mediated vasodilatation in exercising humans J. Physiol., February 15, 2007; 579(1): 227 - 236. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. W. Wray, A. Uberoi, L. Lawrenson, and R. S. Richardson Evidence of preserved endothelial function and vascular plasticity with age Am J Physiol Heart Circ Physiol, March 1, 2006; 290(3): H1271 - H1277. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. J. Donato, A. Uberoi, D. W. Wray, S. Nishiyama, L. Lawrenson, and R. S. Richardson Differential effects of aging on limb blood flow in humans Am J Physiol Heart Circ Physiol, January 1, 2006; 290(1): H272 - H278. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. E. Eklund, K. S. Hageman, D. C. Poole, and T. I. Musch Impact of aging on muscle blood flow in chronic heart failure J Appl Physiol, August 1, 2005; 99(2): 505 - 514. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. F. Towse, J. M. Slade, and R. A. Meyer Effect of physical activity on MRI-measured blood oxygen level-dependent transients in skeletal muscle after brief contractions J Appl Physiol, August 1, 2005; 99(2): 715 - 722. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
