When you build up your running you get fitter, quickly. It turns out that the cardiovascular system adapts more quickly than the muscoloskeletal system. So while my lungs, heart, and capillaries are ready to run 7 flat for an hour, my muscles, bones, and ligaments may buckle.
For me, the feet tend to give way first. My calves tend to tighten up, which can lead to plantar fasciitis, achilles injuries, and general foot pain. The solution is to build mileage and overall intensity conservatively with time. But you can also help yourself with some non-running exercises to build strength and flexibility to support adaptation.
Monday I ran 8 miles on a banked, 0.1-mile indoor track in flats. Soon after I realized I may be taxing my lower legs too much too soon. So I'm thinking it's time to get into some of that "extra" work to support my running. My favorite source for this kind of thing is the venerable Coach Jay Johnson. Here is a 5-minute core workout he recommends for runners.
This is a routine developed for runners. It's tough. I like it for twice or three times a week after a run or in the evening after dinner. There are 10 exercises performed in sequence: 30 seconds each with no rest in between. The killer is the V-Sit scissor kicks.
List of exercises:
- 'Running' V-Sits
- Australian Crawl
- V-Sit Flutter Kick
- Side Plank with Leg Lifts
- Supine Plank with Leg Lifts
- Other side Plank with Leg Lifts
- Pushup to side plank
- V-Sit Scissor Kicks
So far, this workout has slayed me every time. Presumably, as you get stronger, you can do each move with more intensity and speed. The leg lifts on the planks are tough, so maybe to start you just aim for 5x leg lift in the 30 seconds. Eventually maybe the beasts out there can even do the routine twice through. The idea is to add 10 to 15 minutes to your daily routine to do some body weight exercise that will further your running. Even the pros are doing Core X: