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A More Comfortable Method for Hydrostatic Weighing: Head above Water at Total Lung Capacity
Erin White1, Silas Bergen2, Annabelle Berggren1
1Department of Health, Exercise and Rehabilitative Sciences, Winona State University, Winona, MN 55987, USA.
Journal of Functional Morphology and Kinesiology
|March 27, 2024
Summary
Making hydrostatic weighing (HW) more comfortable involves keeping the head above water (HAW) and inhaling to total lung capacity (TLC). This improved method enhances accessibility and enjoyment for body fat percentage (PBF) measurements.
Area of Science:
- Exercise Physiology
- Body Composition Analysis
Background:
- Hydrostatic weighing (HW) is a gold standard for body fat percentage (PBF) assessment.
- The traditional HW method requires full submersion and breathing at residual volume (RV), often causing discomfort.
Purpose of the Study:
- To identify modifications to the HW protocol to enhance participant comfort.
- To evaluate the impact of head position and lung volume on PBF measurements.
Main Methods:
- Three comparisons were conducted: head above water (HAW) vs. head below water (HBW), total lung capacity (TLC) vs. RV, and combined head and lung volume changes.
- Participants (n=122) were analyzed separately for males and females.
Main Results:
- Keeping the head above water (HAW) yielded higher PBF than head below water (HBW) (p < 0.05).
- Measuring PBF at total lung capacity (TLC) resulted in lower values than at residual volume (RV) (p < 0.05).
- The HAW@TLC condition showed significantly lower PBF for males (p=0.003) but not for females or overall compared to HBW@RV.
Conclusions:
- Modifying HW by keeping the head above water and inhaling to TLC improves comfort and accessibility.
- These adjustments maintain accurate PBF results, making the assessment more pleasant for all participants.
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