NCAA runner turned high school coach Hillary Kigar has an answer for all things training–including tips for which surfaces are the least harmful and most energy efficient for your running body.
My office moved to a new building where there’s a crushed gravel path to run on and a treadmill in the free gym. Which is the best running surface?
Usually I would suggest choosing the softer surface (in this case, the gravel path) rather than pounding on the treadmill. However, there are several other factors to think about when deciding where to run. If it’s a very hot day or there’s ice on the ground, run indoors so you can focus on maintaining a steady pace while avoiding the elements. Also, consider if the path is long enough to get a quality run in or if you might get bored and only go around a couple of times before cutting the run short.
When you do a run on the treadmill, make it your easy run of the week and take advantage of the gym by adding core and strength exercises. A good option could be to stay outside every other run to give your body a change in environment and scenery. Remember that fitness is gained when the body is challenged in different ways, so resist getting into too much of a routine!