I'm preparing for an AT thru hike this spring. I'm up to running 3-5 miles 2-3 times a week, and doing a combination of push ups and sit ups at least once week - along with eating healthy this is working great. Since I sit in a cube for upwards of 10 hours a day, I've incorporated exercise into work. I simply hold my feet off the ground while sitting in my chair... At first I could only do it 5 minutes, but now its just a regular part of my day!