I have been taking ATP Extreme for about 2-3 weeks. I am glad that your product does not have any stimulating side effects. I have tried different supplements over a period of time and the ATP is by far the best supplement I have ever used that does what is is supposed to do! First of all, I can get through a workout with more drive, my muscles are more stimulated and I have an awesome pump. Secondly, the supplement allows me the to lift heavier. I am only 113 pounds but I can lift more that I could have ever imagined. Thirdly, my endurance level has increased and this allow me a more intense workout. I am very pleased with your product and eager to spread the word!