Much is made of running shoes and rightly so. The industry would like us to believe that the right shoe will directly improve your PB's. What I think is more accurate, is that the wrong shoes will cause niggles and even injury, and this will inhibit your run progression.
The fanfare around zero drop shoes has thankfully stopped and I sense the trend is now more measured. Zero or minimal drop shoes have been in the mainstream for the last 5 years or so and their limitations have perhaps been exposed.
There is an association between minimal drop shoes and fore/mid foot running. I'm a believer in the latter but have my reservations about super flat shoes especially in the recreational athlete.
The drop of the shoes describes the height in millimetres of the heel compared to the fore-foot. From a biomechanics point of view a minimal drop shoe (<4mm) will ask a lot more from the rear foot and ankle joint. The increased range caused by lower heel, will disadvantage one of the main running muscles: Soleus. It also places the foot-ankle in the more 'unlocked' position.
Soleus is the deep calf muscle and it powers the ankle. It contributes greatly to absorbing the ground reaction force at foot contact. If a zero drop shoe disadvantages this suspension then greater load will be placed on other structures. This can lead to overload injuries. Injuries to bone like medial tibial stress syndrome or the joints like anterior lateral ankle impingement, or injuries to the plantar fascia or achilles tendon are all feasible.
Injuries are rarely this simple and are more often multi-factorial. A detailed assessment is required to determine the layers of an injury. However what can be said is that if you're running in minimal drop shoes and you know you have low soleus strength-endurance then you'll struggle to progress your run performance and put yourself at high risk of a lower limb injury.
Over-pronation is the go to phrase in describing foot mechanics. It's is what everyone dreads but is what most people get branded.
Pronation is an essential movement pattern of walking and running, and therefore the phrase over-pronation can be misleading. Especially when over-pronation is often used to describe any dysfunction or function that is associated with pronation.
Given that stability shoes are designed to control over-pronation. There's no surprise that stability shoes are used more than I believe is necessary. As a physiotherapist I feel much greater emphasis should be made on strengthening the weakness that is causing the dysfunction. It's completely possible to improve 'over-pronation' and increase foot and ankle efficiency. This can be when considering injury but also to enhance performance.