Hello Tom,
I did the C25k program last winter/spring (2013) at age 54, when I hit a weight I was entirely uncomfortable with ( shocked actually!). When I started, I couldn't do the 60 second runs, even a single one! I repeated week one, repeated week 2, but things got easier after that. The aches and pains go away after a few weeks, but those days off are needed!
I did 5 miles this morning......