Definitely, most professional tennis players use some form of supplement.  Have you ever noticed at the change of ends during a match when a professional tennis player has more than one drink bottle and takes a small drink from each bottle.  A common ingredient is a match supplement to provide consistent energy throughout the long points, games and sets. 

Supplements can assist players of all levels to improve their game, and play harder when it matters.

If the professionals are using supplements, why aren’t you?