I’m 67, last tri was IM Wisconsin 7 years ago. Since then I’ve had knee surgery to remove loose cartilage 2 and a half years ago. I walk 4-5 miles daily, bike about 100 miles a week, now running 2 miles 3 times a week on trails. As I recall, IM Wisconsin was about half on concrete and probably the last straw as I started having problems with the knee locking right after the race. Looking to train for a 70.3 in a year and full IM at 2 years if my knees hold up (so far no pain or issues since surgery).
So, which half and full are the easiest on the knees?