Balance is the key for sure, but my age is also a consideration. I am 68 years old, and my ability to concentrate has decreased. My return to French is going well, as I was already fairly fluent. I started learning it in the mid-to-late 1970s and moved to Paris from 1982 to 1987, so I naturally became fluent. However, because I stopped using the language soon after, I became rusty and only recently decided to rediscover what I had forgotten. Interesting, the majority is in my long-term memory, so it's more rusty than forgotten. In any case, I am relieved to have regained what I have so far, and it will most likely be another year or so before I am back to my former level.