Why is it important to think about what shoes you wear when you exercise? Because the type of shoe you wear while performing resisted functional training exercises affects your foot function. Poor foot function can cause a multitude of orthopedic problems including, but not limited to flat feet, knee arthritis, and back pain. So, how do the different types of shoes affect your foot's function?
Modern cushioned shoes are great at dissipating ground reaction forces and were specifically designed to decrease heel strike impact while running. There is continuing debate whether using cushioned shoes rather than our own natural mechanisms to dissipate this impact has been good for us. On one side of the argument, those who promote cushioned shoes say that the stored energy in the shoe helps us move forward and decreases our lower extremity muscle fatigue allowing us to run longer distances faster. On the other side of the argument, proponents of minimalist shoes say that utilizing a more forefoot impact point allows us to use our arch in a natural way to dissipate ground reaction forces. This in turn increases our foot strength and makes us more efficient runners. Current research has not settled this debate. Research shows that people are predisposed towards being a forefoot or hind foot striker while running, and it may be very hard to change this aspect of a persons running gait. Hence there may not be a single best choice for footwear for all.
The evidence is more clear when it comes to comparing cushioned shoes to minimalist shoes while performing resisted functional training exercises. Cushioned shoes isolate your great toe from the ground and make it very difficult to use the muscles on the bottom of your foot when a stable base is needed in most functional lower extremity exercises. Without a stable base of support, one's foot rolls inward causing the knee to follow and the whole lower extremity kinetic chain is disrupted. This disruption causes the patella to track over the lateral femur and compresses the lateral knee joint. It also functionally shortens the limb which can cause back problems.
Wearing minimalist shoes on the other hand, allows for the great toe and plantar muscles to function as it attempts to create a stable base of support. Having strong plantar muscles, especially the flexor of the great toe, helps maintain the medial arch of the foot when the lower extremity is under load. Having a stable base of support and a normal functioning arch has many benefits. Among those are improved knee cap tracking, increased balance, and more efficient lower extremity motion.
So the next time you perform your resistance training exercise, think about the shoes you wear and the function of your plantar muscles.