You have to be very fit and strong to do "hard" martialarts.
要想练“硬”武术，你必须身强力壮。
2
Many times over the years, I have looked back on the days when I confidently practised martialarts and used a gym and wished I felt well enough and confident enough to do those things again.
Do something that's productive and requires concentration, such as writing about your situation, helping someone else with their homework, or practicing martialarts or yoga.