HARD-HITTING PRE-WORKOUT WITHOUT THE INGREDIENTS THAT AFFECT YOUR SLEEP WITH ADDED INGREDIENTS FOR MENTAL FOCUS! Pre-workouts are the most popular category in all of sports nutrition and for good reason – they help you push yourself to the max each time you step into the gym. Fitness enthusiasts looking for an exceptional caffeine-free pre-workout that delivers intense muscle pumps and laser focus can look no further. We’ve got you covered with Mammoth SWELL.