I'm not accustomed yet to working out so vigorously in the evening, so it was hard falling asleep after my return to karate class, and I had trouble falling and staying asleep. So yesterday, the day after my return, I was exhausted. I think I'll adjust with time and be able to fall asleep quicly and well--I did in the past.
One of the good changes about class is that we do more push-ups and more sit-ups/crunches than before--I had been thinking about staying after class to do more, but it's part of the routine now. So in total, we did 75 push-ups--55 at the start of class, in the pattern of 10 push-ups, followed by a rest while counting to 10, then nine push-ups, followed by a nine count, etc.--then two sets of 10 slowly at the end of class. I did the initial 55 with my arms wide, and the final 10 with my arms close to my sides.
And after doing as many sit-ups (feet and bent legs held down by a partner) as possible in 60 seconds (52 for me), we did I think 40 crunches at the end of class, working on both middle and oblique muscles.
So I may be able to get a pretty full resistance training workout by adding tricep raises on a chair and (this will be new to me) pull-ups after class. Maybe some neck work too, though we do some calisthenics related to the neck at the start of class.