Well, I did feel the "tingling" the 1st few days so of course I assumed it "worked". Now that I'm looking back into my log I'm realizing that I have not been taking it for a couple of days and I am still progressing. People said it worked I just assumed the best but I don't like assuming. I like knowing that the product I'm taking is being absorbed into my bloodstream/being utilized by my body 100%. I feel great with the work out maxmizer and I have been using that even before incarnate but the workout maximizer has published studies on it to show that it does exacty what it's supposed to do. Incarnate on the other hand, I'm just taking other people's and the company's word for it that "it works". There's not much scientific substantiation for anything, just word of mouth and the encouragement of fellow people who have tried it. I don't know, I'm going to stop rambling now but all I know is that my progress is exactly the same, if not, better..and I'm off the incarnate. I don't feel I should have to buy another bottle to "see if it works" but we'll see. I have to play it by ear