I think some of ours need two weeks to recover, and at least one is waiting for a knee replacement. Two of us are 57, and the oldest are 73 and 75.
I just hope I'm as fit as them in 15 years - and this is one way to ensure it.
I'll go along with that - it's a tough workout, but I've made some great new friends (down in St Austell, not Portslade). It make you think as well - finding space, and looking for someone to pass to. Most of us are in our 50's, but one is 73. Give it a go!