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Updated: Mar 16, 2026
A Rapidly Incremented Tethered-Swimming Maximal Protocol for Cardiorespiratory Assessment of Swimmers
Published on: January 28, 2020
Do 5% changes around maximal lactate steady state lead to swimming biophysical modifications?
Jailton Gregório Pelarigo1, Camila Coelho Greco2, Benedito Sérgio Denadai2
1University Catholic Center of Quixadá - UNICATÓLICA, Quixadá, Ceará, Brazil; Metropolitan College of Grande Fortaleza - FAMETRO, Fortaleza, Ceará, Brazil; Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, Portugal; Porto Biomechanics Laboratory, LABIOMEP, University of Porto, Portugal.
Elite female swimmers maintained physiological stability at 97.5% and 100% of maximal lactate steady state (MLSS) speeds. However, at 102.5% MLSS, fatigue led to decreased stroke length and increased blood lactate, preventing completion of the 30-minute swim.
Area of Science:
- Sports Science
- Exercise Physiology
- Swimming Biomechanics
Background:
- Understanding physiological responses during prolonged swimming is crucial for optimizing training and performance.
- Maximal lactate steady state (MLSS) is a key indicator of endurance capacity in swimmers.
- Elite swimmers exhibit distinct physiological adaptations to varying intensities.
Purpose of the Study:
- To investigate the biophysical responses of elite female swimmers at velocities around their maximal lactate steady state (MLSS).
- To determine the sustainability of swimming performance at 97.5%, 100%, and 102.5% of MLSS over a 30-minute duration.
- To analyze changes in oxygen uptake, pulmonary ventilation, blood lactate, stroke rate, and stroke length at different intensities.
Main Methods:
- Ten elite female swimmers completed three to five 30-minute constant pace tests at 97.5%, 100%, and 102.5% of their determined MLSS velocity.
- Measurements included gas exchange (oxygen uptake, pulmonary ventilation), blood lactate concentration, stroke rate, and stroke length.
- Data were analyzed to assess physiological stability and changes over time at each intensity.
Main Results:
- Oxygen uptake and pulmonary ventilation increased with swimming velocity.
- Stroke rate and stroke length also increased with velocity, with all variables remaining constant over time at 97.5% and 100% MLSS.
- At 102.5% MLSS, stroke rate increased, stroke length decreased, and blood lactate and pulmonary ventilation rose significantly, leading to fatigue and inability to complete the swim for most participants.
Conclusions:
- Elite female swimmers can sustain physiological homeostasis for 30 minutes at 97.5% and 100% MLSS.
- Swimming at 102.5% MLSS induces significant physiological strain, characterized by increased blood lactate and hyperventilation, ultimately leading to fatigue and performance decrements.
- Stroke length and stroke rate adjustments play a critical role in adapting to different swimming intensities, with significant changes indicating the onset of fatigue.
