I received Tribulus as a free sample. I was very pleased with the results and plan to keep using the product. My recovery times decreased and my lifts gained by 5 lbs and increased my rep range In my first two weeks. It mainly due to recovery. I lift heavy 5 days a week and complete two cardio days on speed, heavy bags and my bike. I am really impressed with Tribulus. Thank You Muscletech for the great products.