ZMA is, of course, not the most popular supplement of all time, but it is widely available and tons of companies, from high-end to low-end, continue to produce it. While the testosterone-boosting benefits of ZMA may be overblown, zinc and magnesium have been shown to have beneficial hormonal effects on their own, so it's not difficult to imagine that that ZMA would have some effect. I didn't take pre/post bloodwork so I can't say anything definitive, but I did find that I was less sore in the morning while taking ZMA and I slept quite soundly, usually through the entire night, which is something I haven't done in ages. The sleep was deep, as even when I couldn't get a full night of sleep, I didn't feel tired. However, I did sometimes feel drowsy in the morning, which I assume was a result of the ZMA. Nothing exciting or new with the profile, but that's ZMA for you. What is nice is that the price on this is quite low where ever you look, so I think it's worthwhile even just if you use it to improve quality of sleep and don't care about potential hormonal benefits...sleep enhances recovery as it is.