Measurement of dehydration status among collegiate athletes following assorted exercise training

Abstract

Introduction: Temperature regulation, thermal and cardiovascular strain, and heat tolerance during sport specific training in warm to hot conditions could directly be modulated by hydration status. However, it remains unclear whether collegiate athletes have knowledge and strategies of optimal fluid intake in sport specific training conditions. The purpose of this study was to assess hydration status associated with fluid intake behavior and patterns for collegiate athletes in different modes of habitual exercise training.Methods: A total of fifty nationally ranked collegiate athletes were recruited from four different sport clubs (men's soccer, n = 13; men's kendo, n = 12; women's handball, n = 12; women's basketball, n = 13) as a category of intermittent exercise. Spot urine was collected within 10 minutes before (Pre) and after (Post) each training session over three consecutive days (Day 1, Day 3, and Day 5) which was randomly chosen for each sport club. A representative value for each sport club at Pre and Post was expressed as a mean value of three consecutive days. Each subject was allowed to drink water ad libitum during each training session over three consecutive days. Exercise training session per day lasted approximately 3 h for each club. For analysis of hydration status, urine specific gravity (Usg) was determined using a handheld refractometer.Results: In terms of urine specific gravity, a two-way analysis of variances (ANOVA) showed significant main effects of time before and after training session in men's soccer (Pre = 1.021 ± 0.007, Post = 1.024 ± 0.006 g/mL, p < 0.05), men's kendo (Pre = 1.021 ± 0.008, Post = 1.027 ± 0.007 g/mL, p < 0.05), women's handball (Pre = 1.025 ± 0.005, Post = 1.027 ± 0.004 g/mL, p < 0.05), and women's basketball (Pre = 1.023 ± 0.008, Post = 1.027 ± 0.005 g/mL, p < 0.05), whereas no significant main effects of day or interactions were found in each club.Discussion and conclusions: The results of the present study suggest that there appears to be a trend for collegiate athletes to be dehydrated even when they take sufficient water fluid. In other words, it is possible for athletes to have insufficient electrolytes such as sodium (which retains water in the body) even when they take plenty of water during exercise training. To minimize fluid deficits, ad libitum consumption of a carbohydrate–electrolyte fluid intake can be more effective than water. Introduction: Temperature regulation, thermal and cardiovascular strain, and heat tolerance during sport specific training in warm to hot conditions could directly be modulated by hydration status. However, it remains unclear whether collegiate athletes have knowledge and strategies of optimal fluid intake in sport specific training conditions. The purpose of this study was to assess hydration status associated with fluid intake behavior and patterns for collegiate athletes in different modes of habitual exercise training. Methods: A total of fifty nationally ranked collegiate athletes were recruited from four different sport clubs (men's soccer, n = 13; men's kendo, n = 12; women's handball, n = 12; women's basketball, n = 13) as a category of intermittent exercise. Spot urine was collected within 10 minutes before (Pre) and after (Post) each training session over three consecutive days (Day 1, Day 3, and Day 5) which was randomly chosen for each sport club. A representative value for each sport club at Pre and Post was expressed as a mean value of three consecutive days. Each subject was allowed to drink water ad libitum during each training session over three consecutive days. Exercise training session per day lasted approximately 3 h for each club. For analysis of hydration status, urine specific gravity (Usg) was determined using a handheld refractometer. Results: In terms of urine specific gravity, a two-way analysis of variances (ANOVA) showed significant main effects of time before and after training session in men's soccer (Pre = 1.021 ± 0.007, Post = 1.024 ± 0.006 g/mL, p < 0.05), men's kendo (Pre = 1.021 ± 0.008, Post = 1.027 ± 0.007 g/mL, p < 0.05), women's handball (Pre = 1.025 ± 0.005, Post = 1.027 ± 0.004 g/mL, p < 0.05), and women's basketball (Pre = 1.023 ± 0.008, Post = 1.027 ± 0.005 g/mL, p < 0.05), whereas no significant main effects of day or interactions were found in each club. Discussion and conclusions: The results of the present study suggest that there appears to be a trend for collegiate athletes to be dehydrated even when they take sufficient water fluid. In other words, it is possible for athletes to have insufficient electrolytes such as sodium (which retains water in the body) even when they take plenty of water during exercise training. To minimize fluid deficits, ad libitum consumption of a carbohydrate–electrolyte fluid intake can be more effective than water.