A well made pair of shoes includes extra protection to avoid issues of discomfort or pain while the feet are under more stress. A midsole section helps to give protection against hard surfaces or objects that are run over. The softer the midsole the greater protection and cushioning it can provide. But, the soft midsole is not the most durable and means it is necessary to replace the running shoes more often.
Overpronation relates to rolling the foot too far inwards while running, which also flattens the arch of the foot. It helps to avoid this foot position because it can jar the knee and tilts the leg inward. The risk of running in this fashion can lead to foot problems like bunions, plantar fasciitis and shin splints. There are plenty of running shoes that are made to fix this specific type of problem. Most of these shoes include a stronger piece of material on the inside edge of the midsole which prevents the foot from rolling.
A high-quality pair of running shoes is also used for fixing issues related to supination which is when the foot rolls outward when running. A downside of running like this is the extra stress put on the bones and ligaments on the outer side of the foot. The best shoes to give protection for supination include those with cushioning in the front and heel, as well as the soft midsole.