Use it or lose it?

Yes, I know it sounds completely cliche', but there's a lot of truth to that expression. I missed a day of reviewing anything Japanese this weekend (bad, I know) and it affected me far more than I ever thought possible - especially since I've only been at it a few weeks. It's kindof like playing an instrument. For instance, I used to play the drums a few years back. I stopped because of time constraints with college. I was so busy trying to finish school projects, build and tweak my portfolio and search for a job in the industry that the drums did little more than collect dust. As a result, I lost most of what I had gained - I can no longer play for 3 hours straight (fast tempo rock type stuff) without batting an eye. Now I'm lucky to play 15 minutes of terribly timed (yet still fast) noise without running short of breath. The same happened with my Japanese. I took a day off, and wound up regressing on my Kanji studies by over 75 characters that I had to re-learn before moving on. Not to mention some of the sentences I'd picked up and didn't use. One thing's for sure - I won't let that happen again.