The Mayo Clinic, in a Dec. 4, 2020 article, "Performance-Enhancing Drugs: Know the Risks," available at, stated:

“Some athletes use stimulants to stimulate the central nervous system and increase heart rate and blood pressure.

Stimulants can:
–Improve endurance
–Reduce fatigue
–Suppress appetite
–Increase alertness and aggressiveness

Common stimulants include caffeine and amphetamines. Cold remedies often contain the stimulants ephedrine or pseudoephedrine hydrochloride.

Energy drinks, which are popular among many athletes, often contain high doses of caffeine and other stimulants. The street drugs cocaine and methamphetamine also are stimulants…

Although stimulants can boost physical performance and promote aggressiveness on the field, they have side effects that can impair athletic performance, including:
–Nervousness and irritability, which make it hard to concentrate on the game
–Insomnia, which can prevent an athlete from getting needed sleep
–Addiction or tolerance, meaning that athletes need greater amounts to achieve the desired effect, so they’ll take doses that are much higher than the intended medical dose

Other side effects include:
–Heart palpitations
–Heart rhythm abnormalities
–Weight loss
–Mild high blood pressure (hypertension)
–Heart attack and other circulatory problems.”

Dec. 4, 2020