While there’s no single definition of what a pre-workout supplement should contain, many include various combinations of caffeine, beta-alanine, creatine, nitrates, and branched-chain amino ...

in comparison to those who did not drink beverages containing caffeine. Most pre-workout drinks come in the form of a powder that people mix themselves. Some companies manufacture ready-to-drink ...

C4 Pre-Workout is a workout supplement line from Cellucor that people may take before exercise to help increase energy, alertness, and strength. They contain caffeine and creatine, which may help ...