I thought I was doing pretty good, going on a week-long Q trip at age 70 late this summer.  I have been totally humbled.  I think your Dad has given me a new goal.  By the time I'm 90, maybe the grandkids will be willing to do the heavy lifting and the serious paddling.  Right now, they are still young enough (8, 9, 10) to think canoeing with gramps is a lot of fun.