Foot Pain and Flip Flops – Summertime Blues Series

May 3, 2010

Flip-flops are a mainstay of summertime footwear, but they can be painfully bad for your feet and legs, new research shows.

Researchers from Auburn University in Alabama studied the biomechanics of the flip-flop and determined that wearing thong-style flip-flops can result in sore feet, ankles and legs.

“We found that when people walk in flip-flops, they alter their gait, which can result in problems and pain from the foot up into the hips and lower back,” said Justin Shroyer, a biomechanics doctoral student who presented the findings to the recent annual meeting of the American College of Sports Medicine in Indianapolis.

For the study, the researchers recruited 39 college-age men and women and asked them to wear flip-flops or athletic shoes. They then had them walk a platform that measured vertical force as their feet hit the ground. A video camera measured stride length and limb angles.

Flip-flop wearers took shorter steps and their heels hit the ground with less vertical force than when the same walkers wore athletic shoes. People wearing flip-flops also don’t bring their toes up as much as the leg swings forward. That results in a larger angle to the ankle and a shorter stride length, the study showed. The reason may be that people tend to grip flip-flops with their toes.