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

Abstract

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 (Ucol), 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 Ucol and FC. There were differences across groups for pre-practice Ucol (P < 0.01) and FC (P < 0.01). GM had a higher pre-practice Ucol than LM (P < 0.01) and NC (P < 0.05) and consumed more fluid than LM (P < 0.01) and NC (P < 0.05). A stepwise linear regression examined the extent that Ucol and FC were related to %BML. When predicting BML, FC accounted for 45% of variance (P < 0.01). The addition of pre-practice Ucol increased predicted variance explained (R2 change= 2.5%, P = 0032). Subjects who gained mass during practice arrived with elevated urine color (Ucol 5 ± 2), while those who lost mass arrived with pale urine color (Ucol 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.

The effect of exercise-induced fatigue and heat exposure on soccer-specific decision-making during high-intensity intermittent exercise

“…Urine osmolality was also measured immediately prior to nude body mass pre-CISP, where participants were asked to provide a urine sample which was subsequently analysed on an osmometer (Osmomat 030, Genotec, Germany). Participants were then asked to provide a urine sample post-CISP, this time following the nude body mass procedure as per previous research [ 50 ], due to needing to account for fluid intake when calculating fluid lost during the trial.…”

Rapid discrimination of urine specific gravity using spectroscopy and a modified combination method based on SPA and spectral index

“…Usually, test strips are widely used to measure USG due to their low price and easy operation. However, it also has several disadvantages, such as the need to consume test strips and unhygienic, which seriously limits the promotion and application of test strips in long-term home health care [4][5][6]. Spectroscopy is simple, rapid, non-invasive, requires no sample pretreatment, and can analyze multiple substances simultaneously [7][8][9].…”