well ive tried it two different times in my life. First time i bought the spray on amazon,com and i loved it at first but actually felt too jacked up on it and stopped it, threw it away. The second time i bought it about 2 years later to give it a try again, but bought a different brand. Didnt do jack shit. so some work some dont. Thats all i can tell you about it. With that said i might try to find one that works again because it does help with workout., however i saw a youtube video that suggested its mostly placebo because its too minimal of an effect to see a difference. So verdict is still out.