What is the main purpose of performance-enhancing drugs?

The main purpose of performance-enhancing drugs is to enhance physical performance. These substances are used by athletes to improve their strength, endurance, speed, and overall ability to perform in their chosen sport. By altering physiological processes, such as increasing muscle mass or enhancing recovery times, these drugs can lead to significantly improved athletic performance.

In contrast, the other options do not align with the primary intent behind the use of these substances. Increasing fatigue and weakness would be counterproductive to an athlete’s goals, while promoting fair competition contradicts the use of such drugs which often creates an unfair advantage. Similarly, focusing on improving the enjoyment of the sport does not address the competitive nature where performance enhancement is sought. Thus, the correct option highlights the central reason some athletes turn to these substances in their pursuit of success in sport.