161 JPJO 6 (2) (2021) 161-168 Jurnal Pendidikan Jasmani dan Olahraga Available online at: https://ejournal.upi.edu/index.php/penjas/article/view/30522 DOI: https://doi.org/10.17509/jpjo.v6i2.30522 Intervention of Hydration Protocol on Strength, Endurance, and Muscle Power Performance Wahyu Syahrul Ramadhan 1 *, Leonardo Lubis 2,3 , Nandina Oktavia 2 , Daniel Womsiwor 4 , Beltasar Tarigan 5 1 Medical Doctor Program, Faculty of Medicine, Universitas Padjadjaran 2 Sciences Department, Division of Anatomy, Faculty of Medicine, Universitas Padjadjaran 3 Sport Medicine Department, West Java National Sport Council (KONI Jawa Barat) 4 Physical Education, Health, & Recreation Program; Faculty of Sport & Health Education, Cendrawasih University 5 Physical Education, Health, & Recreation Program; Faculty of Sport & Health Education, Universitas Pendidikan Indonesia Article Info Article History : Received December 2020 Revised Mei 2021 Accepted July 2021 Available online September 2021 Keywords : Hydration Protocol, Muscle Strength, Muscle Endurance, Muscle Power, Water Abstract Water is a molecule that plays an essential role in the muscle contraction process be- cause muscle is a tissue that mostly contains water (75-80%). Therefore, athletes need to maintain fluid intake to support their physical activities when competing and when training. Nevertheless, in several studies, it was noted that some athletes experienced hypohydration or dehydration, which ultimately impaired muscle performance. There- fore, this study was conducted to determine the hydration protocol intervention on muscle strength, endurance, and power performance. This research is an analytical study with quasi-experimental research methods, namely single-arm pre-post study design using secondary data. Subjects of this study were 69 athletes year 2020 (named consecutively: Muaythai 9, Pencak silat 12, wrestling 10, judo 18, and taekwondo 20 athletes). This research was conducted from December 2019 to January 2020. In the beginning, all athletes were tested for muscle strength using a leg dynamometer, then muscle endurance tests using push-up and sit-up tests, and muscle power tests using the triple hop test of the right and left legs. After the first test, all athletes were educat- ed about the hydration protocol. The hydration protocol was determined based on each athlete's sweat rate (ISR) and the training characteristics of each sports division. Then,  Correspondence Address : Jln. Ir. Soekarno km. 21. Jatinangor, Kab. Bandung. Indonesia E-mail : wahyu17005@mail.unpad.ac.id https://ejournal.upi.edu/index.php/penjas/index 162 INTRODUCTION Water is a molecule that plays a vital role in mus- cle contraction because muscle is a tissue mostly com- posed of water (75-80%) (Pavel et al., 2017b). De- creased water levels in the body can interfere with met- abolic processes and muscle performance, resulting in decreased athlete performance. Good hydration man- agement can prevent athletes from becoming dehydrat- ed, reduce the risk of injury, and maintain good muscle contraction physiology (Pavel et al., 2017a). Nutrition management for athletes is crucial to note. Athletes must pay attention to their nutritional intake, which includes maintaining fluid intake to sup- port their physical activities when competing and when training. However, some athletes do not have sufficient knowledge in fulfilling their fluid needs and doing exer- cises or competing in a state of dehydration, as seen in a study in various sports which showed 31.9% of athletes started training in a state of dehydration, and 43, 6% of athletes are dehydrated after exercise. Also, 52.9% of athletes have low knowledge of nutrition (Magee et al., 2017). Another study on young athletes showed that 89.4% experienced significant dehydration, while 10.6% experienced mild dehydration (Dieny & Putria- na, 2015). In athletes, the primary excretion of fluid during exercise is through sweat. Whole-body sweat rates (WBSR) are generally in the range of 0.5-2.0 L/hr. However, the amount of WBSR can also exceed 3.0 L/ hr in a minority of athletes (about 2%) (Baker, 2017). Excess fluid excretion that is not balanced with ade- quate water intake can cause dehydration. Dehydration in athletes can cause a decrease in the performance of muscle strength, muscle endurance, and muscle power and can even interfere with cognitive function (Magee et al., 2017; Meyer et al., 2016). Other studies have focused more on the effects of dehydration on muscle performance, but few have in- vestigated the effect of hydration protocols on muscle performance. This study calculates fluid needs during individual sports so that each athlete gets the proper fluid intake according to their individual needs. So, the hydration protocol applied in this study was made to improve athletes' performance in training, especially in preparation for the national level Olympics. Therefore, all athletes received hydration protocol intervention monitored independently by themselves and the coach. In addition, the hydration protocol used was also a pro- tocol made by the researchers themselves. Based on the description above, this study aims to investigate the effect of the intervention of hydration protocol on the performance of strength, endurance, and muscle power. METHODS This study is an analytical study with quasi- experimental research methods, namely single-arm pre- post study design using secondary data Participants The subjects in this study were 69 athletes: 9 Muay Thai athletes, 12 Pencak silat athletes, ten wres- tling athletes, 18 judo athletes, and 20 taekwondo ath- letes. The sampling technique used in this research is nonprobability sampling (convenience sampling). Mar- tial arts sports were chosen because they were available and easily accessible to researchers. In addition, martial arts sports also require maximum muscle performance, which a good supply of fluids can support; therefore, hydration protocol is also important for martial arts sports. The independent variable in this study was the hy- dration protocol, while the dependent variables were muscle strength, muscle endurance, and muscle power. This research was conducted from December 2019 to January 2020. First, all athletes were tested for muscle strength using a leg dynamometer, muscle endurance tests with push-up and sit-up tests, and muscle power tests using the triple hop test of the right and left legs. After the first test, all athletes were educated about the hydration protocol used. Then, all athletes undergo the training for two months and have to implement the hydration protocol. Finally, the same tests are repeated at the end of the training. After the data was obtained, the normality test was first performed; the results showed that the data were not normally distributed; therefore, a nonparametric test was chosen to analyze the data. This study aimed to determine the differences in muscle performance before and after the intervention of the hydration protocol. Therefore the Wilcoxon test was chosen to determine Copyright © 2021, authors, e-ISSN : 2580-071X , p-ISSN : 2085-6180 Wahyu Syahrul Ramadhan et. al/ Jurnal Pendidikan Jasmani dan Olahraga 6 (2) (2021) 163 these differences. Procedure The The hydration protocol used in this study con- sists of several stages and rules, namely: 1. Determine the athlete's individual sweat rate (ISR) by: a. Calculate body weight before and after exer- cise. • If the difference is 1 kg, then 1000 mL of ad- ditional fluid is given during exercise. • f possible, measure the volume of urine dur- ing exercise. • Goal: no or <2% weight loss. b. Stable urine color. 2. Emphasize continuous fluid replacement, namely: a. Consume fluids according to the amount of the ISR. b. Adaptation to fluid replacement. c. Increase fluid delivery gradually. d. Allow the body to adapt to increased fluid con- sumption. e. Use individual drinking containers so they can be monitored visually. f. Simply put, the liquid consumed is as much as 0.5-1 cup per 10-15 minutes. (1 cup = 240 mL) 3. Understand the dynamics of each sport, namely: a. Time and duration of rest/break/time-out b. Access to fluids 4. Apply the process of acclimatization or physiologi- cal adjustments to the training process. Symptoms and signs for athletes who have not been acclima- tized will include: a. More sweating d. More electrolyte loss Data Analysis The data obtained will be processed using Statisti- cal Product and Service Solution (SPSS) software ver- sion 23 for Windows. This research uses associative hypothesis testing to find the relationship between the independent variable and the control variable, using the same sample to obtain two groups of data (the group before being given the hydration protocol and the group after being given the hydration protocol), and also the variable data obtained in numerical form so that The analysis was performed using Wilcoxon test, Kruskal- Wallis test, and the Mann-Whitney U post hoc test. RESULT General Characteristics The total number of subjects in this study was 69 athletes. The composition of each sport is shown in table 1. Wilcoxon Signed-rank Test The difference test used in this study was the Wil- coxon signed-rank test to determine whether there was a significant difference between the pre and post hydra- tion protocol intervention on muscle performance. P-value <0.05, it can be interpreted that there are significant differences between the groups before and after being given the hydration protocol intervention. Based on table 2, the results show that there are significant differences in all variables. Copyright © 2021, authors, e-ISSN : 2580-071X , p-ISSN : 2085-6180 Table 1. Characteristics of research subjects Sport Disciplines Male Female Muay thai 6 3 Pencak silat 7 5 Wrestling 5 5 Judo 9 9 Taekwondo 10 10 Variable Pre Test Post Test p-Value M SD M SD Muscle strength 46.5 6.03 49.9 5.85 0.0001 Muscle endurance (push-up) 43.2 8.20 50.0 9.84 0.0001 Muscle endurance (sit-up) 44.5 10.2 51.5 10.5 0.0001 Muscle power (right leg) 5.71 0.73 6.55 0.98 0.0001 Muscle power (left leg) 5.73 0.81 6.54 0.92 0.0001 Table 2. Wilcoxon signed-rank test Wahyu Syahrul Ramadhan et. al/ Jurnal Pendidikan Jasmani dan Olahraga 6 (2) (2021) 164 DISCUSSION The Every day, water is needed by our body in more significant amounts when compared to other nu- trients. Most of the human body is composed of water, namely as much as 55% in the elderly, 60% in adults, while in infants, as much as 75% (Muth & Zive, 2019; Whitney & Rolfes, 2018). 70–80% of the water in the body is contained in many body tissues, such as mus- cles, skin, internal organs, and the brain. Only 10-20% of water in the body is in the adipose tissue and bones. Total body water consists of two-thirds of the total amount of water in the body in the intracellular space, while the other third is extracellular, which includes plasma volume, solid connective tissue, bone, transcel- lular fluid, interstitial fluid, and lymph. The amount of extracellular fluid can describe a person's hydration sta- tus, while intracellular fluid reflects the body cell mass and nutrients (Muth & Zive, 2019; Whitney & Rolfes, 2018) A person is considered to have a good hydration status (euhydration) if he has a normal osmolarity pres- sure (Posm) of 285-295 mOsm/kg regardless of total daily water intake (Armstrong & Johnson, 2018). The water requirement of each individual can vary each day widely depending on age, sex, body weight, physical activity, weather, and the composition of the food con- sumed (Armstrong & Johnson, 2018). Water content in the body and fluid balance is regulated by physiological factors, namely by osmoreceptors and baroreceptors, and non-physiological factors such as social, habit, and cultural influences (Riebl & Davy, 2013). Based on the Dietary Reference Intakes (DRIs) established by the European Food Safety Authority (EFSA), the adequate amount of water intake for adults is 2.5 liters/day for men and 2 liters/day for women. This is slightly differ- ent from the Dietary Reference Intakes released by the Institute of Medicine (IOM), which are 3.3 liters/day for men and 2.3 liters/day for women (Gandy, 2015). Muscle tissue is composed of protein (18-20%) and water (75-80%). In addition, muscle also contains several molecules in small amounts, such as glycogen (0.5-1.5%), glucose (0.02-0.04%), phospholipids (~1%), cholesterol (0.07-0.18%), lactic acid (~0.01%), vitamins, enzymes and some other organic molecules (Pavel et al., 2017b). In general, the role of water in muscle physiology includes acting as a solvent and is involved in various metabolic reactions in muscle cells. Each gram of mus- cle glycogen stores 2.7 grams of water which serves as a medium to facilitate hydrolytic enzymes to break down glycogen into glucose for later use as energy in the process of muscle contraction (Lorenzo et al., 2019). So that if the body lacks fluids in the muscles, it will also interfere with the energy production process, which ultimately results in a decrease in muscle perfor- mance. Besides, water also plays an essential role in maintaining the structural shape of a cell by binding to cytoplasmic proteins and indirectly influencing physio- logical mechanisms such as cell performance and regu- lation of cell proliferation or apoptosis (Lorenzo et al., 2019). Water also plays a vital role in mechanical func- tions, such as maintaining flexibility and elasticity of tissues to prevent injury (Lorenzo et al., 2019). Muscle is a network composed of protein (18- 20%) and water (75-80%). In addition, muscles also contain several molecules in small amounts, such as glycogen (0.5-1.5%), glucose (0.02-0.04%), phospho- lipids (~1%), cholesterol (0.07-0.18%), lactic acid (~0.01%), vitamins, enzymes and some other organic molecules (Pavel et al., 2017a). The protein contained in muscle consists of myo- sin (60%) and actin (12%) which compose the elements of muscle contraction. In addition, there are nucleopro- teins, globulin X, myogen, and myoalbulin that make up the sarcoplasm. And also, myoglobulin (~ 1%) is a muscle that contains oxygen deposits. 1The human body has more than 600 skeletal muscles or 40% of the total muscle, which varies in shape and size (Hall, 2016; Magyari et al., 2018). The constituent structure of skeletal muscles consists of many fibers with diameters ranging from 10 to 80 micrometers. The smallest con- tractile units in muscle are called sarcomeres, which are composed of different proteins. Myofibrils consist of several sarcomeres and a group of myofibrils to form one muscle fiber or cell. In addition, various types of connective tissue, called fascia, surround the muscle structure and create a stable and flexible environment (Magyari et al., 2018). In this study, three components of muscle perfor- mance-testedwere tested: muscle strength, muscle en- durance, and muscle power. Muscle strength is defined as the maximum force or torque of a muscle or muscle that can resist resistance during a specific task (Bagchi et al., 2018; Walton-Fisette & Wuest, 2018). In this Copyright © 2021, authors, e-ISSN : 2580-071X , p-ISSN : 2085-6180 Wahyu Syahrul Ramadhan et. al/ Jurnal Pendidikan Jasmani dan Olahraga 6 (2) (2021) 165 study, muscle strength was tested using a leg dyna- mometer. Muscle endurance is the ability of a group of mus- cles to contract repeatedly over a period of time. This study tested muscle endurance with push-up and a sit- up test (Riebe et al., 2018). Muscle power is defined as the ability to produce a certain amount of force at high speed or a combination of muscle strength and speed (speed) applied in a short span of time (Walton-Fisette & Wuest, 2018). In this study, muscle power was tested by the triple hop test of the right and left legs. The results of the different tests using the Wilcox- on test shown in Table 2 show significant differences in muscle performance in the athletes' group before and after being given the hydration protocol intervention. This difference indicates the relationship between hy- dration protocol and muscle strength, muscle endur- ance, and muscle power. Thus, hydration protocol plays an important role in maintaining the athlete's hydration status at a good level. In other studies, good hydration status has been shown to affect performance in sports, including muscle (Shirreffs, 2005). These results are supported by research showing the critical role of water in metabolism and muscle activity (Lorenzo et al., 2019). The combat sports (i.e., wrestling, boxing, judo, Pencak silat, taekwondo, muay Thai, taekwondo) match their athletes before a competition based on gender and weight class. The weight class aims to make the oppo- nent have the same weight to reduce injuries (Pallarés et al., 2016). Although success in combat sport has many factors, recent research has shown that muscle strength and power are the key factors influencing per- formance in this sport. However, the effects of dehydra- tion and rapid rehydration on neuromuscular perfor- mance (i.e., muscle strength and strength) have not been adequately explored. Weight loss due to dehydra- tion has been shown to affect boxing and wrestling per- formance. However, if weight loss recovers quickly, the effect on performance is not visible. Maximal isometric muscle strength was found to be reduced or unchanged after rapid weight loss. Pallarés et al. found that 4% dehydration reduced muscle endurance, but not knee strength isokinetic, while pH or Pi was independent of hypohydration. However, recent research suggests that hypohydration can impair isometric, eccentric forces, particularly the force development rate. (Pallarés et al., 2016) The hydration protocol intervention has a big ef- fect on keeping the athlete's total body water (TBW) and body mass stable during training activities. In an- other study, decreases in TBW and body mass were noted to reduce muscle performance in athletes (Akan, 2020). Hydration protocols made by MHealthy Physical Activity Program from the Regents of the University of Michigan recommends consuming 500-600 mL of wa- ter 2 hours before exercise, 200-300 mL every 10-20 minutes of exercise, and 500-700 mL after practice (Program, 2014). Meanwhile, according to the American College of Sports Medicine (ACSM), athletes are recommended to consume 5─7 mL of water per kg of body weight four hours before training and consume 450─675 mL of wa- ter per 0.5 kg of body weight lost during exercise. This ACSM recommendation applies to all ages (Smith et al., 2015). In addition, if the athlete's training duration exceeds one hour, then fluids containing 30–60 grams of carbohydrates need to be added every hour (Muth & Zive, 2019; Smith et al., 2015). Good hydration conditions in athletes are very im- portant because if there is a decrease in hydration sta- tus, it will interfere with the physiological work of the muscles. The results of other studies show that hypohy- dration or dehydration conditions in athletes show a decrease in muscle performance such as muscle strength, muscle endurance, and muscle power (Goulet et al., 2018; Judelson et al., 2007; Magee et al., 2017; Meyer et al., 2016; Savoie et al., 2015). Also, hypohy- dration has been shown to cause decreased blood flow and changes in skeletal muscle metabolism (increased lactate, muscle glycogenolysis, and carbohydrate oxida- tion) (Nuccio et al., 2017). Dehydration can interfere with normal physiologi- cal functions. A decrease in blood volume due to a de- crease in the fluid can increase the strain on the heart, thereby decreasing the stroke volume and increasing the heart rate. When the core temperature increases due to exercise and dehydration, the blood flow to the skin increases and further reduces blood from its main flow, further exacerbating the stretching of the heart. Due to the increased blood flow to the skin, sweat production increases as an attempt to remove heat from the body through evaporation (Logan‐Sprenger et al., 2015). Copyright © 2021, authors, e-ISSN : 2580-071X , p-ISSN : 2085-6180 Wahyu Syahrul Ramadhan et. al/ Jurnal Pendidikan Jasmani dan Olahraga 6 (2) (2021) 166 A decrease of 3%-4% of the total water in the body can reduce muscle strength by about 2% (Meyer et al., 2016). A decrease of 3% -4% of body mass can decrease the explosive power of muscles by about 3% —endurance performance, especially in hot weather (Magee et al., 2017). Even mild dehydration (~1-2% weight loss) indicates impaired cognitive performance during exercise (Magee et al., 2017). About 2000─3100 mL of water in the body is ex- creted every day. A total of 1200─2000 mL by the kid- neys (urine), 450 mL by the skin (sweat), 250─350 ml by the lungs (water vapor), and 100─300 mL through the digestive tract (feces) (Riebl & Davy, 2013; Whit- ney & Rolfes, 2018). Humidity, temperature environ- ment, along the intensity and duration of physical activ- ity undertaken also affect the amount of urine output. In cold temperatures, urine output will be more, while it will be less at hot temperatures. In a hot environment, more excreted body fluids are released through sweat (Kenefick & Cheuvront, 2012). Athletes lose sweat and electrolytes due to ther- moregulated sweat during exercise, and it is known that the level and composition of sweat can vary within and between individuals. The WBSR typically ranges from about 0.5 to about 2.0 L/hour (Baker, 2017). However, the amount of WBSR can also exceed 3.0 L/hr in a mi- nority of athletes (about 2%) (Baker, 2017). The hydration protocol also aims to minimize the amount of excessive water intake or less than the amount of water excreted by the body, primarily through sweat. Apart from using water, rehydration can also be supplemented with foods containing water and sodium if the athlete only has 12 hours of recovery time before doing the next strenuous activity. However, if you need quick rehydration, athletes should drink 1.5 liters of water per kg of body weight lost. If you are more than 7% dehydrated, fluid rehydration should be done intravenously (Muth & Zive, 2019). Recent research on the relationship between water and muscle work is discovering the fourth phase of wa- ter or EZ-water, which is directly related to the muscle contraction mechanism (Pollack, 2013, 2018; Yoo et al., 2014). EZ-water or exclusion zone water is a form of the fourth phase of water in which water has properties be- tween solid and liquid, it also has the characteristic of pushing whatever is in it out, so that in this phase, water cannot dissolve anything, so it is called the exclusion zone water. This phenomenon makes water play a role in increasing the density or viscosity of hydrophilic molecules (such as proteins) by up to sixfold (De Ninno, 2017; Pollack, 2013, 2018). The bonding force on the hydrophilic surface with water is a major factor in forming the high-density intermediate phase (viscous interphase). EZ-water (negatively charged) envelops all macromolecules in cells and plays a vital role in meta- bolic and mechanical processes in muscle cells. The increase in the density of the water surrounding the pro- tein does not support the muscle contraction process. The water molecules in the relaxed myofibrils are asso- ciated with hydrogen bonds, with very few free hydrox- ide ions. However, when the muscles contract, there is a large breaking of the bonds in the water hydrogen bonds that surround the protein that plays a role in con- tractility (contractile protein) so that the number of free water molecules increases and forms a water mass. This means that some of the water bonds in the contractile proteins are released when the muscles contract due to the breaking of hydrogen bonds and destruction of EZ- water (Lorenzo et al., 2019; Pollack, 2018). Furthermore, when the myofibrils relax, it appears that they bind to hydrogen extensively with little or no free OH-. In measurements using synchrotron radiation- Fourier transform infrared (SF-FTIR) spectromicrosco- py, it was found that water absorption was relatively higher in the central region of the sarcomere than in the I-band region, implying a higher hydration capacity in thick filaments compared to thin filaments. When myo- fibrils contract, there is a change, namely a significant release of hydrogen from the water. The separation of the amide accompanies the change induced by this con- traction I peak, implying that the muscle protein transi- tions from the alpha-helix to beta-sheet-rich structures. Therefore, muscle contraction can be characterized by a loss of regularity in the muscle-protein complex, ac- companied by changes in the structure of water (Pollack, 2013; Yoo et al., 2014). The mechanism shows how important the role of water is in the process of muscle contraction. In addition, the composition of water that is main- tained in the body can also protect the cardiovascular system and body temperature regulation system. When exercising, sweating is the best temperature-lowering Copyright © 2021, authors, e-ISSN : 2580-071X , p-ISSN : 2085-6180 Wahyu Syahrul Ramadhan et. al/ Jurnal Pendidikan Jasmani dan Olahraga 6 (2) (2021) 167 mechanism to keep your body temperature from rising too high. An increase in body temperature that is too high can cause heat injury as well as a decrease in en- durance performance (Akan, 2020; James et al., 2019). The hydration protocol plays an important role in ful- filling body fluid replacement so that the fluid that comes out is replaced immediately. A good fluid re- placement can reduce excess temperature rise and im- prove performance during training (Akan, 2020). Apart from maintaining good hydration status, training also affects muscle performance improvement. A study on judo athletes during an 8-week training peri- od showed an increase in the components of muscle endurance and muscle power (Mohammed & Choi, 2017). Another study conducted on Mixed Martial Arts (MMA) athletes during a 4-week training period also showed an increase in the components of muscle strength, muscle endurance, and muscle power (Kostikiadis et al., 2018). However, this training varia- ble is one of the confounding factors that bias this study. CONCLUSION Based on data that has been processed through in- fluence analysis tests, it can be concluded that there is an influence of the hydration protocol intervention on muscle performance, namely muscle strength, muscle endurance, and muscle power. The influence of the hy- dration protocol is to maintain a good hydration status (euhydration) in the athlete so that the athlete does not experience hypohydration which will later impair the athlete's muscle performance. Not only in martial arts sports but all sports, it is important to apply hydration protocols individually according to the training program (volume of training). CONFLICT OF INTEREST The authors declared no conflict of interest. ACKNOWLEDGEMENT We would like to deliver our gratitude to West Ja- va KONI for facilitating this research so that it can be implemented. We would also deliver our sincere grati- tude to all participants who had involved in the study. REFERENCES Auxter. at. al. (2001). 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The journal of physical chemistry letters, 5(6), 947-952. https://doi.org/10.1021/jz5000879 Copyright © 2021, authors, e-ISSN : 2580-071X , p-ISSN : 2085-6180 Wahyu Syahrul Ramadhan et. al/ Jurnal Pendidikan Jasmani dan Olahraga 6 (2) (2021)