Hydration Status during Consecutive Two-A-Day Practices in Female Collegiate Soccer Players


Medicine and Health Sciences


Ross A. Sherman


Jeffrey A. Potteiger


It is understood that participation in two-a-day practices, especially in the summer, results in exercise-induced dehydration, inappropriate fluid intake, and substantial body mass loss, however there is a dearth of literature examining soccer players, and in particular females.

PURPOSE: To determine hydration status during five consecutive days of two-a-day practices in female collegiate soccer players.

METHODS: 18 outfield players (19±1 yrs; 167±5 cm; 60.1±4.8 kg) volunteered to be monitored during each morning and afternoon practice across five consecutive days of pre-season (air temperature 26±2°C; 59±16%). Hydration status was assessed for urine specific gravity (USG) from samples provided upon waking, immediately after morning practice and prior to and immediately after afternoon practice. Pre- and post-practice nude body mass, as well as volume of fluid consumed during each practice was also measured. Comparisons were made using two-way ANOVA.

RESULTS: No difference in USG was found across the two-a-days, however players were dehydrated (USG>1.020) at the start of the day for four of the five days. Pre-afternoon USG was significantly lower (p<0.01) than at any other time point (Pre-morning: 1.0204±0.0060; Post-morning: 1.0203±0.0078; Pre-afternoon: 1.0125±0.0076; Post-afternoon 1.0180±0.0066). Players were also found to have a significant (p<0.05) increase in USG overnight on three of the four days (Day 1-Day 2: 0.0038±0.0071; Day 2-Day 3: 0.0036±0.0066; Day 3-Day 4: 0.0035±0.0066). Change in body mass was significantly (p<0.01) different on Day 1 (-1.9±0.5 kg) and Day 2 (-1.9±0.4 kg) compared to Days 3-5, however no differences were found between the morning and afternoon practices. Players drank significantly (p<0.01) more fluid during the morning practice (Morning: 1.11±0.52 L; Afternoon: 0.75±0.54 L) and also on Day 1 (1.37±0.57 L) and Day 2 (1.23±0.34 L) compared to Days 3-5.

CONCLUSION: Players commonly started the day dehydrated, were able to appropriately rehydrate in the break between the morning and afternoon practice, but failed to adequately hydrate after the afternoon practice and before the next morning. Players lost the most body mass during the first two days, even though they consumed the most fluid on those days, and favored the morning practice for increased fluid intake.

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