A lavatory urine color (LUC) chart method can identify hypohydration in a physically active population

Area of Science:

• Sports Medicine
• Physiology
• Diagnostic Methods

Background:

• Accurate hydration status assessment is crucial for athletic performance and health.
• Traditional methods for assessing urine concentration can be time-consuming or require laboratory analysis.
• Hypohydration, or dehydration, can negatively impact physiological function and athletic capabilities.

Purpose of the Study:

• To introduce and evaluate a novel, at-the-toilet-bowl method for self-assessing urine concentration (Uc) using urine color.
• To determine the efficiency and accuracy of this new method in identifying hypohydration among athletes.

Main Methods:

• A cohort of 189 athletes participated, providing urine samples in a lavatory stall.
• Participants selected a color panel based on urine voiding duration, then compared their urine color to the selected panel.
• Trained investigators also assessed urine color, with results compared against urine specific gravity (USG) and urine osmolality thresholds for hypohydration.

Main Results:

• Subject and investigator urine color scoring showed high agreement (P=0.99).
• The lavatory urine color (LUC) method demonstrated fair accuracy, with area under the curve values ranging from 0.73-0.82.
• Classification accuracy for hypohydration was 72% (vs. USG ≥ 1.020) and 62% (vs. urine osmolality ≥ 836 mmol·kg⁻¹).

Conclusions:

• The novel lavatory urine color (LUC) method provides a practical and immediate way to assess hydration status.
• This method yields results comparable to traditional urine color charts.
• The LUC method offers a convenient tool for athletes to self-monitor urine concentration and potential hypohydration.