I used this for about a week and felt nauseous and our of it during and after workouts. Startet taking the EVL BCAA Lean Energy after reading good reviews, than went back to ENGN again and now its amazing. It gives me quite the boost and energy to complete the work out. I take it with Citrulline and Glutamine (which is probably a bad idea ???) and then I take the before mentioned BCAA lean energy post workout and also mid workout if needed.