I'm 36...weigh 193 and I'm 6'2. I am starting back from 0 miles run, but I'm fairly active and I lift weights 3 days a week. Yesterday I went out and ran 3.3 miles at about 9:30 pace. So far I feel fine. Do you still think 20-25 miles a week is ok to start with as long as I am running slow pace? Should I try to incorporate 1 long run each week? Not sure when I am going to run next marathon as I guess alot of it depends on how quickly I can get to a point where I can begin more intense training. My goal would just be to break 4 hours. Before my last marathon I ran a 1/2 in 1:45 but then I had a herniated muscle in my lower leg that really affected my marathon and I ran it in about 4 1/2 hours. I had put in so much training I decided I was going to run it whether injured or not. Probably wasn't best idea.