Assessment of hydration status of elite young male soccer players with different methods and new approach method of substitute urine strip

Abstract

Background: The purpose of the study is to determine and compare the hydration status with different methods and determine fluid intake, dehydration percentages and sweat rate of 26 young male soccer players (15 ± 1.2 years) before an important competition. More specifically, the study aims at validating the urine strip and advising the players to use it as an easy and practical method. Methods: Measurements of urine analysis were taken from the urine sample of the participants before breakfast and conducted for 3 consecutive days before the competition. Hydration status was assessed through analysis of urine color, urine specific gravity (USG) (laboratory, strip, refractometry), and osmolality. The players' dehydration percentages and sweat ratio were calculated. Results:The average values for all samples were 3 ± 1 for color, and 1.021 ± 4 g/cm 3 for USG (laboratory), and 1.021 ± 3 g/cm 3 for USG (strip), and 1.021 ± 4 for USG (refractometry), and 903 ± 133 mOsm/kg for osmolality. USG (strip) was highly correlated with USG (laboratory), USG (refractometry) (r = 0.8; P < 0.01) and osmolality (r = 0.7; P < 0.01), and moderately correlated with urine color (r = 0.4; P < 0.05). The mean dehydration percentage and sweat rate of the soccer players were observed as 0.5 % and 582.3 ± 232.0 mL/h, respectively. Conclusion: We found that youth soccer players are under a slight risk of dehydration under moderate weather conditions. As indicated by the research results, determination of hydration status of athletes must be taken into account more carefully under moderate and hot weather conditions. In addition, hydration methods were compatible with one another as measured in this study.

Sex differences in hydration status among adolescent elite soccer players

“…It should be noticed that different methods and markers may be used to define hydration status. Beyond body mass loss, which defines acute fluid losses, hydration status in athletes is usually monitored by urine specific gravity (USG) (Fernández-Elías et al, 2014;Oppliger et al, 2005), the threshold of >1.020 g/mL being considered an index of hypohydration (Armstrong & Maresh, 1998;Ersoy et al, 2016;Hamouti et al, 2013;Phillips et al, 2014;Sawka et al, 2007). We observed significantly higher USG values in males vs. females in the post-LIB measurements (ES=1.52); this finding further supports the notion that in an ad libitum hydration regimen, at the end of training male soccer players are more dehydrated compared to females.…”

“…Optimisation of athletes' hydration status is an issue of continuing research. The euhydrated state was shown to attenuate thermal, physiological and perceptual strain (Ersoy et al, 2016;Maughan & Shirreffs, 2008). Conversely, improper hydration strategies before, during, and after sport activity not only can impair athletic performance (Cheuvront et al, 2005;Maughan & Shirreffs, 2010), but may also adversely impact athletes' health (Benton et al, 2015;Siegel, 2015).…”

“…Furthermore, a recent study (Buoite Stella et al, 2017) performed on athletes (age: 8-63 years, median: 21±13 years) across all types of sport showed that only 6.5% out of 352 athletes reported fluid intake during their regular training at or above currently NATA and ACSM suggested hydration guidelines, namely drinking between 0.2-0.3 L for every 10-20 min of exercise performed (Goulet, 2012;Sawka et al, 2007). Thus, individual hydration should be monitored to ensure that each athlete is euhydrated before and after sport activity (Ersoy et al, 2016;Maughan & Shirreffs, 2008;Périard et al, 2014).…”

“…The ad libitum strategy of fluid intake, where athletes are free to drink on their will, started to be suggested likely because of the fear that planned drinking might cause overdrinking and thus exercise-induced hyponatremia (Almond et al, 2005;Judge et al, 2016;Siegel, 2015). However, despite the ad libitum strategy is generally expected to avoid detrimental levels of dehydration even in young athletes (Rowland, 2011), it is not always sufficient to result in euhydration (Purcell, 2013;Arnaoutis et al, 2015;Ersoy et al, 2016). Consequently, recent research points to optimise hydration through personalized strategies (Maughan & Shirreffs 2008;Périard et al, 2014).…”

“…Similarly, a group of adolescent male swimmers lost more fluid relative to initial body mass but drank no more than females (Higham et al, 2009). Paucity of information is available on adolescent female soccer players (Gibson et al, 2012), as the majority of studies have been carried out only on males (Arnaoutis et al, 2015;Da Silva et al, 2012;Ersoy et al, 2016;Gordon et al, 2015;Phillips et al, 2014;Williams and Blackwell, 2012). Notably, females can differ from males for many hormonal and physiological characteristics (Cauci et al, 2017;Stachenfeld, 2008), including antidiuretic hormone (ADH) responses through ADH receptors affecting hydration status (Liu et al, 2011).…”