Foot Alignment Clinic LogoCalf Tightness: A common problem in athletes is tight calf muscles, especially in runners. The symptoms are a gradual tightening in the calf muscles which can get worse when running or improve while running only to tighten up later. Why do they tighten up? You might have a compartment syndrome or a bio mechanical problem in your running style and need orthotics. Over pronation commonly loads the lateral aspect of the calf and hence micro trauma to the tissue. (See biomechanics page).