An ergogenic aid is defined by the International Society of Sports Nutrition (ISSN) as anything that can improve performance. Therefore an ergogenic aid per se can include anything from supplements and deliberate nutrition, to a pair of lightweight running trainers!
From a nutritional perspective, some ergogenic aids are based on nothing more than hear say and therefore lack credibility and validity. Below is a non-exhaustive list of a few common supplemental ergogenic aids you might want to consider:
Carbohydrates, Caffeine, Nitric Oxide and Bicarbonate of Soda have all been seen to irrefutably aid performance. Beta Alanine may provide some benefit to staving off fatigue too.
Creatine (mainly monohydrate, but others include ethyl ester and micronized creatine to name a few), Nitric Oxide and L-Arginine.
Protein (whey, casein, egg, soya, hemp, brown rice, pea), ZMA and Fenugreek, Creatine and HMB (mainly for inexperienced lifters, but may be of benefit to experienced lifters too).
Protein (as above), Electrolytes, Vitamins and Minerals and Carbohydrate.
Note: This list is not exhaustive, and it serves well to remember that the MOST BENEFICIAL of all ergogenic aids is WATER! For more info on this subject and much more besides, go check out our blog.