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Post-swim orthostatic intolerance in a marathon swimmer
J B Finlay1, A F Hartman, R C Weir
1Department of Medical Biophysics, University of Western Ontario, London, Canada.
Medicine and Science in Sports and Exercise
|September 1, 1995
Summary
Marathon swimmers may experience fainting and orthostatic intolerance after long swims due to blood pooling in the legs. This condition, linked to the venous muscle pump
Area of Science:
- Sports Medicine
- Exercise Physiology
- Cardiovascular Research
Background:
- Marathon swimming involves prolonged physical exertion in aquatic environments.
- Understanding physiological responses to extreme endurance events is crucial for athlete safety.
- Orthostatic intolerance and syncope are potential risks in endurance athletes.
Observation:
- A well-trained marathon swimmer experienced orthostatic intolerance and syncope after two long-distance swims (33 km and 38 km).
- Elevated creatine phosphokinase (CK) levels were noted post-swim, indicating muscle damage.
- Rectal core temperature remained above 37.0°C, suggesting thermoregulation was maintained.
Findings:
- Post-swim orthostatic intolerance and syncope were attributed to blood pooling in the legs.
- Inactivation of the venous muscle pump mechanism after prolonged swimming is the proposed cause.
- Intravenous saline infusions effectively relieved the orthostatic intolerance.
Implications:
- This case highlights the importance of monitoring cardiovascular responses in ultra-endurance athletes.
- Strategies to mitigate blood pooling and support venous return post-exercise may be beneficial.
- Further research into the specific physiological mechanisms of exercise-associated collapse in swimmers is warranted.