When it comes to footwear, selecting the right shoe is more than just what color we think looks best. Yes, we want to look good but, we also want to feel good. In regards to gait mechanics, running terrain, competition, or potential injury, the type of shoe you are wearing can make a huge impact on your running efficiency and injury risk. To simplify things, there are 2 main factors to consider when selecting your next pair of shoes; the amount of stability provided and heel-toe offset.
Before determining what type of shoe would be best for you, we need to know your foot type and gait mechanics. The easiest way to do this would be to have your physical therapist running shoe store employee perform an assessment of your feet and biomechanics. If you are wanting to check at home, a simple way to assess your gait mechanics is to look at the wear pattern at the bottom of your shoe. This can give clues to how much or little pronating you are doing. Pronating refers to the inward roll of the ankle during gait. (See the image below for example.) To assess your arch height, stand with your shoes and socks off. We are looking for how much space there is from the floor towards the middle of your foot. Normal arch height would be about 2 finger widths from floor to foot.
There are three primary shoe types you will find on most store shelves. Neutral, stability, and motion-controlled. While there are other kinds out there, minimalist for example, those three are the most common so we will focus on understanding the differences.
Neutral running shoes Neutral running shoes are designed for those with normal arch height and neutral pronation during gait. These are the most common shoes found in stores and are generally acceptable for most people. Because these shoes do not offer a lot of extra support, they tend to be lighter. The lighter the shoe the more efficient we can be with less energy required for each step. Neutral running shoes can also offer another benefit in that they typically accept orthotics better. Since there is no added support, the shoe and insole will not be fighting against one another which could otherwise offer too much support. Neutral running shoes typically have the same color foam along the entire sole of the shoe.
Motion-controlled shoes These shoes are designed for the individual with excessive overpronation during the gait cycle. This individual will typically have a lower arch height, if not flat feet. They require an increase in support towards the arch and improved stability towards the fore and hind foot. Motion controlled shoes, due to the added stability they provide, will be stiffer than a neutral shoe. This added stiffness and control however comes with the downside of being a heavier shoe. These shoes often have a hard piece of plastic around the heel as well as a difference in color from the sole of the heel compared to the rest of the shoe.
Stability running shoes Stability running shoes are in the middle when comparing neutral to motion- controlled. The individual who would benefit from this will have a neutral to low arch height and a slight increase in pronation during gait. These shoes provide more support at the arch while still offering benefits of shoe flexibility and weight. Stability shoes will typically have a darker piece of foam or material along the arch of the shoe.
Heel-Toe Offset
The next thing to consider when choosing your shoes is the heel-toe offset or "drop". This refers to the difference in stack height (height of the sole of the shoe) from the toe box to the heel. Minimalist shoes typically will have 0mm offset meaning that the difference in sole height from the toe to heel is zero. This resembles walking barefoot. It can be argued that this is the ideal offset to have as it best mimics how our foot was designed to function. However, this is not the case for most people because our bodies have accommodated to wearing supportive or cushioned shoes. Changing to a zero-drop shoe without having an assessment by a physical therapist and then going through a specific strengthening protocol can cause injury. When deciding the amount of heel-toe offset, one must consider many factors including body type, footstrike, and injury/areas of pain.
Most running shoes average between 8mm-14mm heel-toe offset. This higher offset offers more cushion towards the heel making it ideal for an individual who is using these shoes for walking, or who has a tendency to heel strike. A person with a higher BMI would also benefit from a higher offset as this will offer more cushion at the heel. When we raise the heel, we are also taking stress off of the achilles tendon and the calf muscles as they will be in a shortened position. This makes a shoe with a higher offset a good option for an individual dealing with plantar fasciopathy or achilles tendinopathy, for example.
A more experienced runner may do well with a heel-toe offset of less than 8mm. These shoes are ideal for a forefoot or midfoot strike pattern as there will be less support in the heel. These shoes will typically be lighter in weight allowing for a better running economy overall. When trying to improve running efficiency or cadence, changing to a lower drop shoe can be a good strategy as it will promote a mid-foot strike. A lower offset shoe can also be beneficial for an individual with forefoot pain as the foot is in a more neutral alignment (as opposed to the heel being higher), causing reduced forces through the forefoot.
While a few millimeters may not sound like much when changing between heights, it can have a big impact. As physical therapists, we advise our patients to change the heel-toe offset by only two mm for every 350 miles (the typical lifespan of the shoe) to allow for the body to safely accommodate the lower drop. In addition, we also recommend alternating between the lower drop shoe and the previously worn shoe for several months. The lower drop shoes are a good choice for speed work days, and the higher drop shoe for longer, easy runs.
While the above information may seem daunting, it scratches the surface of selecting the perfect shoe for you. To keep it simple, determining the best type of shoe between neutral, stability, and motion control will be enough for most recreational runners. If you are recovering from an injury or looking for strategies to improve your performance, altering your offset or other factors could be viable options. It is always best to contact an expert who can guide you towards the right shoe for your body. The investment in the correct shoe will pay dividends in the long run!