Surveys across the board show that about 50% of athletes report taking supplements, though what is defined as a supplement is not clear. What is clear is that although many top athletes take supplements, supplementation is not a prerequisite for being the best in your chosen activity, or even for reaching your personal best, since the other 50% of athletes don't use them!! Never the less, some supplements (such as vitamins and minerals) can play a valuable role in a winning diet.