after your body is beat, not just from the gym, but after a long day of rucking and your body aches. I find comfort in knowing, once I get to my chu and take this stuff, my body will feel like in a trance, pain melts away and I knock out happily. tho it is a challenge to open the bottle knowing that it will smell like a sweaty locker room, but the taste is great, mixes easy as well. I recommend to try it, it will help you relax your body. though it doesn't really make you sleepy it just helps you get there and help you feel refreshed in the morning.