Normally, when you walk or run, your heel is the first part of your foot to strike the ground. As your body weight shifts to the middle of the foot, the arch of the foot naturally flattens out a bit. This flattening is called pronation. If your feet flatten more than normal, it?s called over-pronation or flat feet. Over-pronation can cause many problems, such as an Achilles tendon injury or heel pain. It may lead to knee problems.
Excess stress on the inner surface of the foot can cause injury and pain in the foot and ankle. Repeated rotational forces through the shin, knee, thigh and pelvis also place additional strain on the muscles, tendons and ligaments of the lower leg.
In addition to problems overpronation causes in the feet, it can also create issues in the calf muscles and lower legs. The calf muscles, which attach to the heel via the Achilles tendon, can become twisted and irritated as a result of the heel rolling excessively toward the midline of the body. Over time this can lead to inflexibility of the calf muscles and the Achilles tendon, which will likely lead to another common problem in the foot and ankle complex, the inability to dorsiflex. As such, overpronation is intrinsically linked to the inability to dorsiflex.
Look at the wear on your shoes and especially running trainers; if you overpronate it's likely the inside of your shoe will be worn down (or seem crushed if they're soft shoes) from the extra strain.
Non Surgical Treatment
Your podiatrist will look at your current footwear to ensure that it is both well-fitted and possessed of adequate cushioning to protect your feet. Firm heel support is advised for over-pronators, and a good fit is important to ensure that the foot as a whole is well supported as instability can exacerbate the existing problems caused by over-pronation.
Wear supportive shoes. If we're talking runners you're going to fall in the camp of needing 'motion control' shoes or shoes built for 'moderate' or 'severe' pronators. There are many good brands of shoes out there. Don't just wear these running, the more often the better. Make slow changes. Sudden changes in your training will aggravate your feet more than typical. Make sure you slowly increase your running/walking distance, speed and even how often you go per week. Strengthen your feet. As part of your running/walking warm up or just as part of a nightly routine try a few simple exercises to strengthen your feet, start with just ten of each and slowly add more sets and intensity. Stand facing a mirror and practice raising your arch higher off the ground without lifting your toes. Sit with a towel under your feet, scrunch your toes and try to pull the towel in under your feet. Sitting again with feet on the ground lift your heels as high as you can, then raise and lower on to toe tips.