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Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
The maximally attainable VO2 during exercise in humans: the peak vs. maximum issue
J R Day1, H B Rossiter, E M Coats
1Department of Physiology, St. George's Hospital Medical School, London, United Kingdom.
A plateau in oxygen uptake (VO2) is not always seen during maximal incremental exercise. However, the peak VO2 achieved during such tests is a reliable indicator of maximal oxygen uptake (VO2 max).
Area of Science:
- Exercise Physiology
- Cardiopulmonary Function
- Metabolic Assessment
Background:
- Maximal oxygen uptake (VO2 max) reflects integrated physiological system function.
- Quantifying VO2 max typically requires observing a plateau in oxygen uptake (VO2).
- The consistency of VO2 plateaus during incremental exercise is debated.
Purpose of the Study:
- To determine if a VO2 plateau consistently occurs during maximal incremental ramp cycle ergometry.
- To compare peak VO2 (VO2 peak) from ramp tests with VO2 determined from constant-load tests.
Main Methods:
- Breath-by-breath analysis of ventilatory and pulmonary gas-exchange variables.
- Maximal incremental ramp cycle ergometry.
- Maximal constant-load tests.
Main Results:
- A VO2 plateau was not consistently observed during ramp exercise.
- VO2 peak from ramp tests did not significantly differ from extrapolated VO2 or VO2 from constant-load tests.
- In a subset of subjects, VO2 peak was either lower (plateau) or higher than extrapolated values.
Conclusions:
- A plateau in VO2 is not an obligatory finding during incremental exercise.
- Peak VO2 achieved during maximal incremental tests is a valid surrogate for VO2 max.
- Further testing may be needed for definitive VO2 max confirmation.
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