## 4 Discussion
These results suggested that electrolyte drinks can prevent water loss in the body by increasing water retention and reducing urine volume during dehydration associated with exercise [5,24]. Body water loss due to exercise is regulated by a water-regulating hormone that responds to changes in body water to maintain water homeostasis [25]. Renin, a body water-regulating hormone, is a type of proteinase released from the renal glomeruli as a response to hypernatremia associated with TBW loss. Renin secretion is known to increase the secretion of aldosterone, an adrenal cortex hormone, and to regulate water balance by stimulating the secretion of ADH released from the posterior pituitary gland [26]. In this study, after consuming regular water and an electrolyte drink before and after exercise, ADH, aldosterone, and renin did not show an interaction effect between the different periods of intake and types of fluids. Hormone concentrations showed a tendency to increase at P0 and, then, decreased again at P1, with no significant difference between the CON and 3 RINK groups. [PERSON] and [PERSON] [27] reported that there was no change in the secretion of renin and aldosterone upon ingestion of fluids with different sodium concentrations after treadmill exercise-induced dehydration in five male college students. In a study by [PERSON] et al. [28] involving 11 adult male individuals, consuming electrolyte drinks before and after performing exhaustive exercise did not induce any changes in ADH. These findings were consistent with the results of this study and were attributed to the intake of sodium contained in the electrolyte drinks, which abolishes the hyponattemic trigger for secretion of renin and aldosterone. In addition, at P1, ADH was found to be higher in the 3 RINK than in the CON group. This could be conducive in the maintenance of water homeostasis because of increased water reabsorption and reduced urine excretion [5,24]. Electrollyte balance is required to maintain normal cell function and plasma volume. Sodium, which is abundantly present in the ECW, plays a role in maintaining plasma volume and osmotic equilibrium between the ECW and the ICW. Potassium is an electrolyte present in the ICW that helps regulate osmotic pressure and plays an important role in nerve stimulation and muscle contraction [29]. Our analysis of body water and electrolytes after consuming the two types of fluids before and after exercise revealed a significant difference in terms of sodium levels at P0 and P1. In addition, a significant difference was found in P0-R for the sodium, hemoglobin, and hematocrit levels with 3 RINK intake. In a study by [PERSON] [30], five male college students received glycerol-enriched water and regular water at 2 h before exercise. Sodium and potassium were found to be significantly increased in the group that received glycerol-enriched water. Although a reduction in sodium concentration was observed due to the release of sweat during exercise, the levels were more stable in the glycerol than in the regular water group by the end of the exercise, suggesting increased water retention in the body and increased ion reabsorption. In contrast to the results of the above study, our study showed that sodium increased at P0, and decreased to a level similar to that at rest at P1. In addition, at P1 there was a significant increase after receiving 3 RINK compared to that after receiving CON. The amount of water that exits into the interstitial water to maintain plasma osmotic pressure leads to a decrease in water loss and increase in absorption [31]. Therefore, unlike the intake of regular water, electrolyte water allows quick recovery of the loss of body water by increasing water absorption rate, which faciliates rebalancing of water homeostasis. Hemoglobin, which carries oxygen, and hematocrit, which indicates the ratio of red blood cells in the blood, are used as indicators of plasma volume and are important factorsin exercise performance [32; 33].