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Exercise physiology

David M Systrom, MD, FRCPC
Gregory D Lewis, MD
Section Editor
James K Stoller, MD, MS
Deputy Editor
Helen Hollingsworth, MD


Physical exercise requires the coordinated interaction of ventilation, cardiac output, and systemic and pulmonary blood flow to meet the metabolic demands of contracting muscles, as skeletal muscle metabolism can rise quickly to 50 times its resting rate during heavy exercise. To preserve cellular oxygenation and acid-base homeostasis during exercise, metabolic, cardiovascular, respiratory responses must adapt rapidly to these dramatic changes in tissue demands.

The normal physiologic response to exercise will be reviewed here. The role of exercise testing to evaluate reduced exercise tolerance due to dysfunction of the respiratory or cardiovascular systems is discussed separately. (See "Functional exercise testing: Ventilatory gas analysis" and "Exercise ECG testing: Performing the test and interpreting the ECG results" and "Approach to the patient with dyspnea".)


Minute ventilation – Volume of air exhaled per minute, VE

Oxygen uptake (L/min) – VO2

Maximum oxygen uptake – VO2max

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Literature review current through: Nov 2017. | This topic last updated: Jul 05, 2016.
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