AUTHOR=Lopez Rebecca M. , Lund Dallin C. , Tritsch Amanda J. , Liebl Victoria 

TITLE=Relationship Between Pre- and Post-exercise Body Mass Changes and Pre-exercise Urine Color in Female Athletes

JOURNAL=Frontiers in Sports and Active Living

VOLUME=4

YEAR=2022

URL=https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2022.791699

DOI=10.3389/fspor.2022.791699

ISSN=2624-9367

ABSTRACT=<p>Although studies use body mass changes or urine color to measure hydration status, the purpose of this study was to examine the relationship between pre-practice urine color and exercise body mass changes in female tackle football players. Twenty-six female American football players (Age: 29.9 ± 7.3 years; Height: 165.2 ± 2.6 cm; Weight: 83.8 ± 24.4 kg) volunteered. Fluid consumptions (FC) was measured during tackle football practices, while urine color (U<sub>col</sub>), and percent body mass loss (%BML) were taken before and after practices. Subjects were grouped by %BML: lost mass (LM), gained mass (GM), or no change (NC). A one-way ANOVA compared groups on U<sub>col</sub> and FC. There were differences across groups for pre-practice U<sub>col</sub> (<italic>P</italic> &lt; 0.01) and FC (<italic>P</italic> &lt; 0.01). GM had a higher pre-practice U<sub>col</sub> than LM (<italic>P</italic> &lt; 0.01) and NC (<italic>P</italic> &lt; 0.05) and consumed more fluid than LM (<italic>P</italic> &lt; 0.01) and NC (<italic>P</italic> &lt; 0.05). A stepwise linear regression examined the extent that U<sub>col</sub> and FC were related to %BML. When predicting BML, FC accounted for 45% of variance (<italic>P</italic> &lt; 0.01). The addition of pre-practice U<sub>col</sub> increased predicted variance explained (<italic>R</italic><sup>2</sup> change= 2.5%, <italic>P</italic> = 0032). Subjects who gained mass during practice arrived with elevated urine color (U<sub>col</sub> 5 ± 2), while those who lost mass arrived with pale urine color (U<sub>col</sub> 3 ± 2). Findings indicate those who arrived with an elevated urine color attempted to improve hydration status by consuming more fluid and gaining body mass during exercise.</p>