Anatomy of a Running Shoe
By: Terri Rejimbal
The upper? The forefront? The outsole? What does this all mean???
If you're like most of us, you haven't paid too much attention to the anatomy of your shoes. As a runner, the more you understand the language of running shoes, the better the chances you'll buy the right pair of shoes that meet your physiological needs and personal preference. If your feet aren't happy, it's difficult to have an enjoyable run. So let's get started!
Shoes should feel comfortable. If you're like me, I prefer a shoe that fits like a glove, sock-less, and with no excessive stitching on the upper that can cause friction. Others prefer to leave between a 1/2 inch to a thumb's width between the end of the shoe and the end of your longest toe, not necessarily your big toe. Running shoes can be as much as a half to a full size bigger than your regular shoe size, since your feet will swell when you run and need plenty of room in the toe box.
The shoe needs to be wide enough to accommodate your foot’s width. Too little and it can put pressure and strain on your metatarsals and the nerves along the foot. Too much width, and your foot can slide and cause blisters along the side, underfoot, and arch of the foot. Or perhaps your foot tries to grip the insides of the shoe to steady itself, causing foot strain. When trying on shoes, go with your socks and any insole you wear, so you can get the best fit and feel before making a purchase.
Breakdown of a Running Shoe
Outsole – Typically made of rubber to provide traction. Contributes to how soft or firm the shoe feels along with the torsion rigidity or flexibility of the shoe. However, sometimes it’s an extension of the foam composite to shred shoe weight.
Midsole – The middle section between the insole and above the outsole, usually composed of foam or rubber, or back in the day – “air” (i.e., Nike Air). Midsole material composition dictates durability or longevity, as well as the ride of the shoe. Cushioning and pronation control materials, i.e., shank/posting, are located here.
Upper – Wraps around the feet, includes the lacing and tongue. Usually mesh material with overlays, stitched or molded on for structure.
Toe Box – Front portion space of the upper above and around toes. Should be roomy to allow foot to expand and toes to splay. It shouldn’t feel tight, nor pinch nerves or metatarsals. Toes shouldn’t hit toe box tip, which can cause pain and damage to toenails.
Heel Collar – Foam padding surrounding sides and rear of shoe and holds your heel in place. Collar can be narrow or wide. If it’s too wide, the heel slips and you may need to adjust lacing to cinch the heel. If it’s too high, it can rub the Achilles tendon.
Forefoot – Shoe part that wraps and supports the ball of the foot. It should flex with your natural gait at the ball of your foot. If it’s too rigid, it could put strain on your ankle and metatarsals, causing serious foot problems.
Midfoot – Shoe part that wraps around and supports the arch, behind the forefoot yet before the heel. It should cradle your foot’s arch and feel supportive. Some shoes fit better for those with low or medium arch vs. a high arch. Aftermarket insoles/custom orthotics can assist in arch support.
About the Author
Terri Rejimbal is a competitive Masters athlete, a 3-time winner and 8-time Masters champion of the Gasparilla Distance Classic Half-Marathon; 6-time Disney Masters Marathon winner, 6-time Florida USATF Athlete of the Year, and a New Balance product tester. Terri is a RRCA certified running coach and is available for consulting or coaching services. Contact Terri at or Instagram @bayshorerunner.