Fatigue pp 393-399 | Cite as

An Integrative View of Limitations to Muscular Performance

  • J. A. Dempsey
  • M. A. Babcock
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 384)

Abstract

First we describe the changing site of limitation to maximal O2 transport with increasing fitness in mammals. The capacity for diffusion and airway/parenchymal flow rate and volume are markedly overbuilt in the sedentary subject’s lung, but undergo little change with increased training/fitness; accordingly, as demand for O2 transport increases in the highly fit, the limits for maximal diffusion and ventilation are surpassed or met at maximal exercise. Secondly, low-frequency diaphragmatic fatigue occured with by heavy endurance exercise. This fatigue resulted from increased diaphragmatic work together with the major contribution from the secondary effects of increased locomotor muscle activity; namely, metabolic acidosis and increased requirement for blood flow.

Keywords

Endurance Exercise Apply Physiology Inspiratory Muscle Fatigue Threshold Body Exercise 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • J. A. Dempsey
    • 1
  • M. A. Babcock
    • 1
  1. 1.The John Rankin Laboratory of Pulmonary Medicine, Department of Preventive MedicineUniversity of Wisconsin-MadisonMadisonUSA

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