TY - JOUR T1 - The effect of three weeks of β-alanine and creatine supplementation on the response of creatine kinase, lactate dehydrogenase and lactate to an exhausting swimming session in elite swimmers TT - اثر سه هفته مکمل دهی بتاآلانین و کراتین بر پاسخ کراتین کیناز، لاکتات دهیدروژناز و لاکتات به یک جلسه تمرین شنای وامانده ساز در مردان شناگر نخبه JF - RJMS JO - RJMS VL - 28 IS - 6 UR - http://rjms.iums.ac.ir/article-1-6589-en.html Y1 - 2021 SP - 90 EP - 99 KW - Muscle injury KW - Creatine kinase KW - Lactate dehydrogenase KW - Beta-Alanine KW - Creatine N2 - Background & Aims: One of the consequences of intense exercise is muscle injury, pain and muscle sorenes. Symptoms of muscle injury include the appearance of intramuscular proteins in the blood and long-term decline in muscle function, decrease in strength and power, flexibility and dynamic muscle speed (1). Muscle damage is associated with the release of creatine kinase and lactate dehydrogenase enzymes and can be measured by the release of these enzymes into the blood. Creatine kinase (CK) is a key enzyme involved in muscle cell metabolism that accelerates the conversion of creatine to phosphate or inverse. increase in this substance in the blood may be sign of muscle damage and inflammation (3). Lactate dehydrogenase (LDH) is an enzyme that is found in large quantities in the cytoplasm of all body tissues at different concentrations and in the conversion of pyruvic acid to lactic acid or inverse in the anaerobic glycolysis pathway accelerates this reaction (3). studies have reported muscle damage by measuring CK and LDH levels during the interval between sets (4), high-intensity training (5), muscle contractions (6, 7), speed training (8) and aerobic training (9). On the other hand, exercise increases the concentration of lactate in the blood. It has been shown that nutritional interventions and the use of antioxidant supplements can be one of the best ways to protect against muscle damage caused by exercise (1). Creatine, an unnecessary dietary compound, can either come from exogenous sources such as fish or meat, or it can be produced endogenously by the body primarily in the liver. Creatine was produced by two-step process from the three amino acids arginine, glycine and methionine (15). In addition to creatine, the amino acid β-alanine is a newer supplement for those interested in professional sports. Beta-Alanine is a precursor of carnosine (β-alanine -histidine); Which can increase the concentration of carnosine in muscles (13,17). Studies have reported the benefits of beta-alanine supplementation in variety of laboratory protocols (19). Researchers are looking for ways to improve performance, prevent unwanted changes in muscle injury indexes, or at least minimize them. Therefore, the present study aims to investigate the effect of three weeks of β-alanine and creatine supplementation on the response of creatine kinase, lactate dehydrogenase and lactate to an exhausting swimming session in elite swimmers. Methods: In this semi-experimental study, 21 elite boy swimmers 15 to 20 years were selected as sample and divided into three groups: 1) supplementation of beta-allanine (daily dose of 2 tablets 1500 mg))2), supplementation of creatine (4 and 2 servings of creatine monohydrate 5 g) (3) placebo (the amount of 2 capsules containing wheat flour). During supplementation, the subjects performed their daily workouts for three days a week (1.5 hours of swimming at distance of 1200 meters) (22). The exhausting exercise protocol was performed in three stages: warming, progressive and lactate tolerance training. Blood samples were collected before, immediately, 15 and 30 minutes after training. Data were analyzed by repeated measures ANOVA and Bonferroni post hoc test at the P<0.05. Results: Three weeks the supplementation of β-alanine (P=0.007) and creatine (P=0.001) significant increase LDH levels in response to exhausting swimming session. No significant difference was observed in the CPK changes in the supplemented groups of beta-alanine, creatine and placebo. The use of creatine supplementation significantly decreases LDH in elite swimmers (P=0.02). Significant increase in lactate levels was observed after three weeks of supplementation of creatine in response to exhausting swimming session (P=0.001). Conclusion: The findings of this study were consistent with the results of Previous research (23,25,26). According to previous studies, beta-alanine supplementation is responsible for the buffer system, carnosine, antioxidant role, enzymatic regulator and calcium control in the sarcoplasmic reticulum (13,17,19). Mechanism and pattern of changes (increase) of serum total creatine kinase enzyme following aerobic training is mainly due to leakage due to energy loss and instability or damage due to peroxidation of cell membrane phospholipids (30). decreased muscle strength and dysfunction due to decreased sarcoplasmic calcium is due to continued muscle contraction and intracellular calcium accumulation and its inability to return to sarcoplasmic cells (27). increasing muscle carnosine with positive effect on muscle cell calcium increases the function of muscle contraction protein and consequently, increases the efficiency of contractile motor units (13,17,19). Therefore, due to metabolic adaptations and increased buffering capacity which is caused by the consumption of beta alanine, no significant changes in creatine kinase enzyme were observed after beta-alanine consumption. Beta-alanine is one of the supplements that athletes use to increase performance and reduce fatigue (13). Beta-alanine supplementation affects aerobic and anaerobic capacity, increases exercise intensity, improves performance, increases carnosine and histidine, changes in hydrogen ion levels in blood and reduces fatigue (13). It seems that taking beta-alanine supplementation increases ability of athletes to exercise more intensely. In general, several factors such as the period and amount of supplementation before the activity, the size and speed of absorption of supplements during the activity, the diet of the subjects before and during the study and the training status of the participants and a combination of the above factors can affect the response of the muscle injury indicators. According to the results, it seems creatine have a greater effect on cell membrane consolidation, and the use of beta-allanine supplements, increases the individual's ability to perform a more intense exercise. M3 ER -