If you're a competitive runner and run 4-6 days a week, you can substitute a low-intensity cross-training workout for an easy run or a rest day on 1-2 days week.

Re-choose your shoes. Low-top running shoes may be perfect for an indoor track, but once you start hitting dirt trails and rocky pathways, you'll need the support of a trail-runner.

The runner has distinctly low level in energy index and discharge capacity as well.