- Creatine is one of the most popular dietary supplements, and its consumption grows intensively worldwide. Beginning from 1992-1993, sales volume of creatine as a dietary supplement used in sports, has taken the first place amongst the other supplements as it substantially increases muscular endurance while intensive physical exercises . It is important to note that creatine is not classified as doping agents. Despite increasing popularity of this supplement, there are still a lot of questions about its efficiency, safety and side effects. There were 3 experiments described below regarding creatine influencing stamina (muscular endurance).
Creatine and taurin test
- The purpose of this experiment was to learn how creatine uptake during physical loads affects sportsmen performance and whether there is any harmful effect on the body associated with such a supplementation.
- A group of 35 healthy, energetic US Army volunteers consisted of 20 males and 15 females, 22-36 year old, at Fort Sam Houston, Texas, was given 7 days` dietary supplementation with 20g/day creatine or taurine as placebo for the experimental purposes. Taurin is an amino acid that is formed in the body, which speeds up the process of removing toxins and is used in dietary supplementation. Our body is able to synthesize taurine, as well as to lose it while intensive loads and stress.
- During the research, scientists estimated the impact of short course of oral creatine on physical exercise performance, blood pressure and kidneys function. Apparently, there wasn`t any remarkable difference in 2-minute push-up counts for creatine and taurine subjects, while supplementation. The ones who were taking creatine showed an impressive growth in serum creatine levels in comparison with the taurine group. That fact might make us think that the former group of subjects experienced kidney failure. Nevertheless the data collected showed that there weren’t any changes in blood pressure, body composition, weight loss or gain, or serum creatine phosphokinase level (evidences of kidney failure), which indicates a benign effect of creatine on our body.
- Hence we can sum up that short-term creatine supplementation doesn`t have any destructive influence on our body, which means-it`s absolutely safe, however doesn`t bring any benefits to push-up performance consequently.1
Creatine and dextrose test
- It has been proven that creatine can soften increase in plasma ammonia (plasma ammonia levels in adults ranging from 9 to 33mol/L. It helps to maintain acid-base balance. Plasma ammonia levels might witness the severity of liver damage) and hypoxanthine (plasma hypoxanthine levels in humans reflect hypoxia- the lack of oxygen in body tissues), while 1 hour intensive endurance exercises. It’s suggested that creatine may enhance muscle energy balance during the procedure, maintaining sufficient ATP re-synthesis according to the demand (ATP is produced by almost all living things in organelles called mitochondria found in cells. It is not energy itself, but rather temporarily “stores” energy in its bonds. When the third phosphate bond is broken, energy is released). It was hypothesized that creatine supplementation would improve muscle energy balance (as assessed by muscle inosine monophosphate (IMP) accumulation) during intense endurance exercise.
- Seven well-trained men participated in the two tests, which included intense endurance exercise (cycling) lasted roughly for one hour. The subjects were not aware of the particular order of supplements uptake.
- The outcome of the two trials reflected that creatine supplementation significantly increase total muscle creatine leading to their enhanced endurance. During first 45 minutes of physical loads there wasn’t any noticeable changes in muscle or blood metabolite measurements between treatments. Notwithstanding the performance ride completion time was almost the same in the two tests (approximately 13,5 minutes, muscle inosine monophosphate was significantly lower in creatine supplemented group), which may lead us to following conclusions.
- To sum up, improvement of the ability of the muscle to maintain energy balance while intense aerobic exercise(swimming, jogging etc) is provided by raising total muscle creatine before physical loads, but it doesn’t occur during more moderate exercise.2 The more intense the physical load while creatine supplementation the better effect regarding the development of stamina.
Effects of creatine loads on muscular strength and stamina in female football players
- The purpose of this test was to determine the effects of creatine on the trained women and the impact of anaerobic exercise performance before the creatine uptake and disappearance of effects on the performance. Usually anaerobic exercise works on muscles, in particular, toning and shaping them. It also provides power and stamina. Anaerobic exercises push a person to move at increased speeds or greater effort while doing them. This helps the body burn more calories. The cells inside the human body require oxygen to break down fat for energy. While doing anaerobic exercise, oxygen supply decreases, and instead of breaking fat, carbohydrates are burnt for energy.
- The twenty six females were randomly divided into particular groups. During 4 weeks of the experiment different doses of creatine in the form of the food supplement as well as placebo were given to the objects. Some of them ingested high dose up to 20 g/day the other ones lower doses, namely, 2-3g/day, while different forms of exercises were being performed. The measurements were conducted at the end of the second, the third and the last week of the experiment. The data collected from these groups of subjects differ significantly, depending on the loads and the patterns of supplementation. Those ones who had constant physical loads associated with high doses of creatine uptake showed the best result in their performance.
- 20 g creatine supplementation a day for a week to the trained females improves not the maximal static strength and dynamic peak torque but the mean strength and endurance of repeated contractions. However, the effects on females are not as great as in males. The effects are enhanced by anaerobic exercises performed before the supplementation and would disappear in a week if the supplementation were stopped.3
- The effect and safety of short-term creatine supplementation on performance of push-ups. Armentano MJ1, Brenner AK, Hedman TL, Solomon ZT, Chavez J, Kemper GB, Salzberg D, Battafarano DF, Christie DS.
- Med Sci Sports Exerc. 2005 Dec;37(12):2054-61. Creatine supplementation reduces muscle inosine monophosphate during endurance exercise in humans. McConell GK1, Shinewell J, Stephens TJ, Stathis CG, Canny BJ, Snow RJ.
- J Sports Med Phys Fitness. 2003 Dec;43(4):481-7. Effects of creatine loading on muscular strength and endurance of female softball players. Ayoama R1, Hiruma E, Sasaki H