Lol! I can appreciate this!
I have found many people older than me can run circles around me.
Some of the people I used to play basketball with are still running and still playing ball in community leagues. I run into them often and I feel very embarassed when they say, "Hey, come play with us on Thursday night!"

I have to explain that I cannot do so. I really cannot. I have been disabled for a very long time now (over 30 years). The various "conditions" have taken a toll , even though, in the beginning, I was determined I would stay fit! I was able to do so for many years... Later on, not so much.

I find senior classes are about my speed, too, and hanging out with them often saves me from an injury! I can gain a lot of strength and range of motion in that level of class(es).

I hope you get what you need from your class!