What's 25 years?

I took my son (and one of his friends) down to the dojo this afternoon - well he actually asked to go. I gave them a 40 minute bag workout. Waiting with anticipation for a text tomorrow about sore shoulders. It was a great workout. I threw in some overhead lifts with steel bars and a lovely long plank session, when I got to yell at them to keep their knees up. They are younger, stronger and fitter than me, but I made them sweat. Next time I choose the music!