In the last few years there has been an ongoing debate in the running industry regarding footwear. At one extreme are the barefoot and minimalist running shoe proponents who argue that no shoes or at most, shoes with minimal structure, are best. On the other end are experts who hold that the traditional thick soled, cushioned shoes are optimal for injury prevention.
Traditional Running Shoes
Until the 1970’s running shoes were manufactured with flat, thin-soles. Indeed the current growth in popularity of minimalist shoes can be seen as a case of old becoming new again.
In the late 70’s and early 80’s running shoe construction began incorporating thicker soles with elevated heels. The rationale for adding cushioning in the midsole and motion control features in running shoes was to absorb impact forces and control movement, specifically pronation, of the foot.
This rationale however was probably misguided. Cushioning materials in shoes actually increases overall leg stiffness (Bishop et al. 2006). Some leg stiffness is beneficial to running well but excessive leg stiffness may be a factor for increased risk of injury (Hewett et al. 2004).
A review study by Richards et al in 2008 concluded that the prescription of “pronation control, elevated cushioned heel (PCECH) running shoes to distance runners is not evidence-based.”
Additionally, a study by Ryan et al in 2010 showed that motion control shoes had the highest incidence of injury in their research group, regardless if the wearer had highly pronated feet or not.
There is good evidence that the shoe construction of the last thirty years or so has not accomplished what it was originally intended to do. Injury rates in runners today remain as high as ever.
Since Christopher MacDougall published Born to Run in 2009, there has been tremendous growth in the number and styles of so-called minimalist shoes. Virtually every major shoe manufacturer and a number of smaller upstarts now have minimalist shoes.
These shoes were designed to mimic how the foot functions barefoot. Generally, running barefoot will cause a runner to land with a flatter foot (De Wit et al 2000).
In addition, Lieberman et al. (2010) found that if a barefoot runner lands with a forefoot landing there is no impact transient (a very rapid rise in impact forces) as compared to landing heel first in shoes. It should be noted however that Lieberman and his group do not claim that heel striking in and of itself causes injury.
Minimalist shoes share the following characteristics:
Minimalist Shoe Heel Drop
Within the minimalist shoe category are three main sub-categories: