Though I am not fully convinced as to the efficacy of the product, I do believe that there is something happening in terms of my sex drive and libido. I am very physically active and am at the gym working-out three times per week with very difficult exercise work-outs ran by a trainer. However, I am 71 years old and simply not feeling like I would like to feel in terms of vigor, strength, and stamina. I feel some improvement and hope to see continued benefits.