I'm 63 and had a total hip replacement in November of 2006. After surgery I was able to run up to 50 miles/week on a treadmill and only 5 miles/week outdoors. I had to curtail my running after rotator cuff repair in December of 2007, but have now gotten back to 40 miles/week on the treadmill, 30 miles/week on a stationary bike, and 45 minutes of outdoor running once a week. I can only run a short time outdoors until I get hip pain, but I get none on the treadmill at the same speed. I have been lifting weights and stretching for my hip since surgery. Before my shoulder surgery I did a 5K in 27:28 (I had run 22:15 at age 61). What workouts do I need to do to break 27 minutes for 5K?