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Updated: May 22, 2026

A Rapidly Incremented Tethered-Swimming Maximal Protocol for Cardiorespiratory Assessment of Swimmers
Published on: January 28, 2020
VO2 kinetics during heavy and severe exercise in swimming
D M Pessoa Filho1, F B Alves, J F Reis
1Human Performance Laboratory, Physical Education, Rio Claro, Brazil.
This study examined oxygen uptake (VO2) kinetics in swimmers above and below the respiratory compensation point (RCP). Results show VO2 kinetics are similar below and above RCP, with RCP acting as a key physiological boundary in swimming.
Area of Science:
- Exercise Physiology
- Sports Science
- Cardiorespiratory Function
Background:
- Understanding oxygen uptake (VO2) kinetics is crucial for optimizing training and performance in swimming.
- The respiratory compensation point (RCP) is a key intensity marker in exercise physiology, but its role in swimming VO2 kinetics is not fully understood.
Purpose of the Study:
- To describe and compare VO2 kinetics above and below the respiratory compensation point (RCP) during swimming.
- To investigate if RCP serves as a physiological boundary for heavy- versus severe-intensity exercise in swimming.
Main Methods:
- Nine well-trained swimmers underwent incremental and square-wave exercise tests to determine gas-exchange threshold (GET), RCP, and VO2max.
- Pulmonary VO2 kinetics were analyzed during swimming transitions to speeds just below (S - 2.5%) and above (S + 2.5%) the RCP speed.
Main Results:
- The time constant of the primary VO2 component was similar below (17.8 ± 5.9 s) and above (16.5 ± 5.1 s) RCP.
- The amplitude of the VO2 slow component was comparable between intensities around RCP.
- VO2max was reached only during the trial above RCP (103.0 ± 8.2% VO2max).
Conclusions:
- VO2 kinetics exhibit similar characteristics below and above the RCP in swimming.
- The RCP functions as a physiological boundary, differentiating heavy-intensity from severe-intensity exercise domains in swimming.
- Findings align with critical power concepts observed in cycling exercise.
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