The effect of short-term consumption of creatine and beta-alanine on the mechanical properties of knee muscles at speeds of 60 and 180 degrees per second.

Dissertation for receiving a Master's degree (M.A)

Trend: Sports Biomechanics

Abstract

Aim: The use of authorized sports supplements in recent years is one of the most important parts of an athlete's preparation. It has become a competition. Despite the many researches that have been conducted in the field of supplements, there is no general consensus on improving performance, and the effects of these two supplements on many factors of physical fitness have not been compared. Therefore, the present study was conducted with the aim of the effect of short-term consumption of creatine and beta-alanine on the mechanical characteristics of the knee muscles at speeds of 60 and 180 degrees per second. Research method: The research method is semi-experimental, applied, and the research design is causal-comparative. For this purpose, 40 male students of physical education and sports sciences of Khwarazmi University volunteered. And they were randomly divided into 5 groups of 8 people: creatine, beta-alanine, creatine-beta-alanine, placebo and control, then the maximum torque, time to reach the maximum torque, torque development, maximum power and acceleration time of the knee extensor muscles of the superior leg at angular speeds of 60 and 180 degrees per second were measured by the isokinetic device, then they took the supplements for 5 days, the creatine group 20 grams, the beta-alanine group consumed 6 grams per day, the creatine-beta-alanine group consumed 20 grams of creatine and 6 grams of beta-alanine per day, and the placebo group consumed 5 grams of glucose per day, the same tests were performed again.

Findings: short-term consumption of creatine and beta-alanine on the mechanical characteristics of knee muscles at speeds of 60 and 180 degrees per second in maximum torque, time to reach maximum torque, development Torque, maximum power and acceleration time of knee extensor muscles have no significant effect.

Key words: creatine/ beta-alanine/ isokinetic contraction/ power/ peak torque/ time to peak torque/ acceleration time/ peak power

Chapter One

(general research)

1.1. Introduction

Using authorized sports supplements in recent years has become one of the most important parts of an athlete's preparation to compete. Due to the importance of increasing the performance of athletes in competitive sports and approaching records in national and international competitions, the use of permitted sports supplements has become one of the most important parts of an athlete's preparation to participate in the competition field in recent years (Moon, 2013). From the point of view of tournament organizers, managers, coaches and most athletes, two points are important when using supplements: 1: use of permitted supplements, 2: use of substances that have maximum efficiency with minimum side effects (Wilmore and Casteel, 1377). Considering the above, in recent years, hundreds of nutritional supplements for athletes have been offered in the market, among which creatine and beta-alanine can be mentioned. Today, creatine is widely used as the simplest supplement by athletes of different ages and championship levels, especially by strength athletes (Habibullah Nia, 2010). Creatine is a non-structural protein in muscle contraction, but it can be combined with phosphate at high levels to form phosphocreatine. Therefore, considering that most of the energy is provided from ATP and creatine phosphate during intense activities and before the start of the anaerobic glycolysis process, it seems that the increase in creatine phosphate reserves will probably increase the amount of ATP produced during very intense activities (Nizam al-Islami, 2013). The basis of using creatine is increasing creatine and phosphocreatine and delaying premature fatigue caused by the breakdown of ATP and phosphocreatine. The increase of phosphocreatine reserves in athletes of various sports fields, especially strength fields, whose activity is more dependent on supplying energy from the phosphagen system, is of particular importance.. In various disciplines, especially power, which relies heavily on the supply of energy by the phosphagen system, the increase of this immediate source, which also acts as a buffer of hydrogen ions, can increase the success of athletes (Sheikh al-Islami Watani, 2012). Also, the use of creatine as a proton (hydrogen) buffer can interfere in the process of glycolysis and lead to the improvement of sports performance (Nizam al-Islami, 2011). Creatine supplement was used for the first time in the 1992 Barcelona games, however, its use has not been prohibited by legal authorities (Sheikh al-Islami, 2004). Another food supplement that has recently been considered as a performance-enhancing agent is beta-alanine (?A) (Roberges et al., 2004). Beta-alanine is a non-protein amino acid that is synthesized in the liver. The main source of beta-alanine in the body is food. Meat is the main source of dietary beta-alanine (Sprite et al., 1989). The performance-enhancing feature of beta-alanine supplementation may be due to increased levels of carnosine in the body (Allen et al., 2008). Carnosine (beta-alanine-L-histidine) is a dipeptide in muscle tissue that acts as an intracellular buffer of hydrogen ions (Messonier et al., 2007). A decrease in pH is known as one of the causes of fatigue and decreased muscle strength and contractile performance. Therefore, beta-alanine supplementation can be useful in improving performance. According to the above explanations, it should be said that nowadays supplements have found different audiences and enthusiasts in different fields and the number of users of these supplements has increased over the past few years. According to previous documents about the effect of supplements on improving the performance of athletes, in this research, the effect of short-term consumption of creatine and beta-alanine on the mechanical characteristics of the knee muscles at speeds of 60 and 180 degrees per second is investigated.

2.1. Statement of the problem:

Due to the importance of increasing the performance of athletes in competitive sports and approaching records in national and international competitions, the use of permitted sports supplements in recent years has become one of the most important parts of an athlete's preparation to appear in the competition field (Ran et al., 2010). From the point of view of tournament organizers, managers, trainers and most athletes, two points are important in supplement consumption, 1: use of permitted supplement and 2: use of substances that have maximum efficiency with minimum side effects (Sheikh al-Islami, 2014). According to the above, the use of creatine monohydrate supplement as an authorized sports supplement is in the program of many athletes at the professional, semi-amateur and amateur sports levels. Therefore, in line with the increase in the use of creatine supplements, the attention of researchers has also been drawn to it, and a lot of research has been done in this field. For example: in a research on the effect of creatine supplementation along with strength training on increasing strength in middle-aged and elderly people, the results of the study showed that creatine consumption along with strength training increased muscle strength in both age groups (Gutshalk et al., 2002). In another study titled the effect of 28 days of creatine consumption on muscle performance and metabolism in road cyclists, the improvement of performance after creatine consumption was reported, and the results of their research showed that muscle metabolism after creatine consumption is followed by less lactate accumulation. Also, in recent years, some studies in the field of supplement consumption have investigated the effects of beta-alanine on performance and improved the total work performed, fatigue time, physical work capacity at threshold. They reported the fatigue of productive power at lactate threshold. Studies say that taking beta-alanine supplements with a possible increase in tamponine capacity causes fatigue to be delayed and improves recovery in periodic periods. Also, some studies have pointed to the increase in anaerobic capacity and power as a result of beta-alanine supplementation. But some studies done in this regard do not confirm the above. In general, according to the functioning of beta-alanine in intramuscular hydrogen buffering, it is expected that the supplemental consumption of this amino acid can affect anaerobic performance. However, by reviewing past studies, it was found that there is no general agreement between the results of studies regarding the effect of beta-alanine and creatine on performance, and that the effects of these two supplements on many factors of physical fitness have not been compared.