"Lateral shin splints (sometimes called anterior shin splints) are
usually due to overuse and inflammation of the anterior tibialis muscle and the
muscle compartment in the front of the leg, along the outside front of your
shin. The anterior tibialis muscle flexes your foot upward. People frequently
get anterior shin splints from the repetition of flexing the muscle. For
instance, on the treadmill, if you walk fast enough, and for long enough, or if
you've suddenly increased the speed, or you're walking on an elevation, the
muscle gets overworked and starts to cramp. It would be like doing hundreds of
biceps curls until your arm started to cramp. Plus, on the treadmill, there's no
letup since the mill just keeps going. You could potentially have the same
problem if you walked or ran briskly outdoors for a long period of time at a
speed faster than you're used to."
