I'm not intended to train for TOEIC test on Sunday, but I have been making myself exposed to materials in English. Bloomberg TV, News feed on Twitter, etc. And then I come to be tired to touch English sentences and talks in the internet.
But keeping touch with information in both English and Japanese is quite a fan. Using other languages is good for many people to see the world, especially Japanese people, I think.
Of course it's tough for my brain, but it's challenging like training my physicals. You can train your brain even if you are over 40.
Writing fuzzy sentences in English like me is also good.