The use of substances by athletes to enhance their performance has been a feature of competition since ancient times. Athletes took these substances to improve their strength and overcome fatigue, and this practice continues to this day. Today, in many sports, these performance-enhancing substances have become even more prevalent. Some common examples of these substances are: steroids, erythropoietin, human growth hormone, and stimulants. This essay will focus on stimulants. Stimulants have long been used in competition, for example, Thomas Hicks won the 1904 Olympic marathon after taking a combination of stimulants (strychnine and brandy) [1]. However, using stimulants to enhance performance can have adverse health effects. For example, Tommy Simpson collapsed and died during the 1967 Tour de France. Say no to plagiarism. Get a custom essay on “Why Violent Video Games Should Not Be Banned”?Get the original essay The stimulants he took (alcohol and amphetamine) were partly blamed for his death [1]. Since then, stimulants have been on the banned list and their use in competition has been banned [2]. Regardless, stimulants, whether legal or illegal, are always taken by athletes because they want to improve their performance in order to gain an advantage over others in order to win. Research has shown that the reason for athlete's competitive gain is mainly due to stimulants that increase alertness, anaerobic performance, endurance and decrease fatigue [3]. Therefore, this essay will review the literature to see how different stimulants (i.e. amphetamine, ephedrine, caffeine, and cocaine) enhance athletic performance to give an athlete a competitive advantage. Amphetamine Amphetamines were first synthesized in 1920 and were widely used during World War II to increase alertness and fatigue [4]. It stimulates the central nervous system (CNS) and causes the release of norepinephrine from sympathetic nerves by reflecting sympathetic neuronal activity, as well as clearing dopamine from the brain [5]. Thus, amphetamines cause an increase in these neurotransmitters (dopamine and norepinephrine), leading to physiological consequences, such as an increase in heart rate and blood flow to the muscles [1]. Propose the possibility that amphetamines may enhance athletic performance due to their stimulant effects. Obviously, an article by Gene et al. [6] supports this, as it reveals that amphetamine significantly improved performance and that athletes felt that this stimulant improved their strength, coordination and endurance. To add, Avis et al. [7] shows that the positive effects of amphetamines include higher levels of physical energy and mental fitness, as well as those who use them feeling more confident and efficient. Additionally, in a randomized crossover trial of cycling at different RPE intensities (hard or very hard), amphetamines allowed participants to sustain higher work rates and longer metabolic and cardio-respiratory levels, whereas they perceived the exercise as not being that hard. even when working at a very hard representative RPE [8]. For example, exercise is prolonged by a stimulant acting on the CNS [8]. Indicating that this stimulant is an ergogenic aid to performance. However, continued consumption of this stimulant may have adverse effects onhealth. For example, side effects associated with amphetamines are confusion, palpitations, rapid breathing, hypertension, tachycardia, and tremor [9]. Ephedrine Ephedrine is the purified form of an ephedra alkaloid, a sympathomimetic amine known for its stimulant properties [10]. These include acting as a CNS stimulant and stimulating alpha and beta adrenergic receptors [7]. Additionally, this type of stimulant has been shown to contribute to athletic performance and weight loss [4]. This is why they are used by athletes. Regarding weight loss, Shekelle et al. [11], a meta-analysis reveals that ephedrine can promote moderate weight loss for up to 6 months, but there are no data on long-term weight loss. Regarding performance, a double-blind crossover study investigating the effect of 24 mg of ephedrine on physical performance reported that ephedrine does influence blood pressure and heart rate during exercise and recovery, but that it does not improve any measures of physical work (strength, endurance). , and power) [12]. In contrast, Bell et al. Study results [13] reveal that ephedrine significantly improved power output during the first phase of a cycle test (Wingate). Another study by Bell et al. [14] shows that a dose of 0.8 mg/kg of ephedrine improved the running times of 12 athletes in a 10 km race from 46.9 ± 3.3 minutes to 45.5 ± 2.9 minutes. These results indicate that this stimulant can be used as an ergogenic aid during prolonged exercise such as long-distance running. The possible ergogenic effect exhibited by ephedrine could be due to the fact that this stimulant increases the release of monoamines such as dopamine at the central and peripheral level [10]. Caffeine Caffeine is consumed in various forms and enjoyed by millions of people, including athletes. The effect of caffeine is to reduce fatigue, increase alertness and wakefulness [15]. Research has demonstrated that low to moderate doses of caffeine (3 to 9 mg/kg) have a significant impact on exercise performance [16,17]. This is further supported by a double-blind crossover study [18]. The study found that different amounts of caffeine consumed improved the performance of fifteen triathletes and cyclists during a one-hour cycling time trial. Furthermore, a meta-analysis by Doherty and Smith [19] quantified the effect of caffeine on different exercise protocols (short-term, high-intensity exercise, and time to exhaustion). They report that caffeine impacts whole-body exercise and has a greater effect on the time-to-exhaustion protocol (effect size = 0.63) compared to the short-term protocol (effect size = 0.16). Altogether, caffeine ingestion has been shown to increase an individual's endurance levels [20]. It appears that athletes consume caffeine because of its ergogenic benefits. The putative beneficial effects of caffeine on performance may be attributed to the fact that it exerts its effect through the intracellular oxidation of free fatty acids and that it acts as an antagonist of adenosine receptors in the CNS [21]. However, its influence on performance is probably due to its role as an adenosine receptor antagonist [9]. In other words, the beneficial effect of caffeine on performance results from the fact that it directly affects the CNS. Therefore, caffeine also has potential side effects. For example, low doses cause anxiety, gastrointestinal discomfort, and inability to concentrate, while high doses can cause arrhythmias and mild hallucinations.,."