I added it in about 8 years ago and I used to suffer from what I call "drag ass" because I was in a very hard training mode and I'd just drag ass all the time because my body always needed more rest no matter how much I gave it. Rhodiola was recommended by a guy I was training with and within 2-3 weeks, I found that I was getting more energy throughout the day and sleeping better. Then I realized I was able to deal with stress better and not get bogged down.
Hope that helps. It is a great supplement that I highly recommend.