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Updated: May 18, 2026

Evaluation of Fluid Overload by Bioelectrical Impedance Vectorial Analysis
Published on: August 17, 2022
Lack of awareness of fluid needs among participants at a midwest marathon
Sara Brown1, George Chiampas, Carrie Jaworski
1Loyola University Medical Center, Chicago, Illinois.
Background:
Marathon running has become popular, particularly among inexperienced runners.
Hypothesis:
Many marathoners are inexperienced and lack concern for potential complications of marathon running.
Study Design:
Cross-sectional survey.
Methods:
In sum, 419 runners completed a survey on a variety of topics regarding training for a marathon and hydration strategies.
Results:
Overall, 211 females (38.3 ± 9.1 years old) and 208 males (41.6 ± 11.0 years old) participated. They trained for 6.8 ± 4.3 months and had run for 9.8 ± 9.1 years; 33.5% had no marathon experience and 16.9% had run 1 marathon. Of the injuries reported, 77.6% and 72.9% were minor musculoskeletal injuries during the current and previous running seasons, respectively. Of the 278 runners who had run a marathon, 54 (19.0%) had been treated in the medical tent, 31.5% of whom for dehydration. Furthermore, 54.9% and 64.3% of the survey participants were "not at all" concerned with musculoskeletal injury and hyponatremia, respectively. Also, 88.7% did not know their sweat rate; 67.8% did not weigh themselves; and 81.3% had no other method of hydration assessment. No significant correlations were found between concern for hyponatremia and age, sex, or experience.
Conclusions:
Most participants were inexperienced, lacked concern for injury or hyponatremia, and were not using methods of hydration assessment.
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