Nutrition and medication are very important among athletes to maintain optimal physical capacity. Competitive sports athletes have to stand out by any means possible so they have a strict diet, with well calculated micronutrients, supplement on nutritional supplement that can enhance their performance, and some do to the extent of taking illegal medications to boost their performance. doping with performance enhancement drugs have been categorised based on either its effects on causing skeletal muscle hypertrophy known as anabolic performance enhancement drugs and those that do not increase muscle mass but enhances performance in other ways e.g., endurance, respiratory, cardio vascularly or anti catabolically known as non-anabolic performance enhancement drugs. They can also be categorised based on their pharmacological mode of mechanism e.g., selective androgen receptor modulators (SARMs), β2- adrenergic agonists, oestrogen receptor (ER) and peptide-hormones like growth hormone (GH), insulin-like growth factor-1 (IGF-1) and insulin. The aim of this thesis is to analyse indebt the mode of mechanism of the most common performance enhancement drugs, how they affect the body and performance of an athlete over time, side effects and compare them with nutritional supplements that can enhance performance