Final answer:
Anabolic steroids, erythropoietin (EPO), and human growth hormone (hGH) have the most research supporting their ability to enhance exercise or sports performance, however, they present serious health risks and are banned by sports governing bodies.
Step-by-step explanation:
Among the substances discussed in the context of exercise and sports performance, anabolic steroids and hormones like erythropoietin (EPO) and human growth hormone (hGH) have notable research indicating their effectiveness in enhancing athletic performance. Anabolic steroids are known to help build muscle mass, while EPO boosts the production of red blood cells, thereby enhancing oxygen delivery to muscles for improved aerobic respiration. Human growth hormone facilitates muscle mass building and recuperation of tissues post-exercise.
However, despite their effectiveness, the utilization of these performance-enhancing drugs raises serious ethical concerns and health risks, leading to their prohibition by many sports governing bodies and making their non-medical use illegal. Amino acid supplements, on the other hand, have not been shown to provide a significant advantage to athletes over maintaining a healthy diet, according to various studies.
Therefore, while certain drugs and supplements have shown potential to enhance performance, their associated risks and the ethical implications of their use lead to strong advisement against their use outside of medical necessity.