The ubiquitous rubber shoe has become standard summer footwear for women of any age, but new research suggests that wearing flip-flops for prolonged periods of time could lead to pain and injury.
Auburn University (AU) researchers have found that wearing thong-style flip-flops can result in sore feet, ankles and legs. The research team, led by biomechanics doctoral student Justin Shroyer, presented its findings at the recent annual meeting of the American College of Sports Medicine in Indianapolis.
“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,” Shroyer said. “Variations like this at the foot can result in changes up the kinetic chain, which in this case can extend upward in the wearer’s body.”
Not to get too scientific but the researchers, in the AU College of Education’s Department of Kinesiology, recruited 39 college-age men and women for the study. Participants, wearing thong-style flip-flops and then traditional athletic shoes, walked a platform that measured vertical force as the walkers’ feet hit the ground. In addition, a video camcorder measured stride length and limb angles.
The AU team found that flip-flop wearers took shorter steps and that their heels hit the ground with less vertical force than when the same walkers wore athletic shoes. The subjects hit the platform with less straight-down force when they wore flip-flops, another result of an altered gait.
It turns out that when wearing flip-flops, the study participants did not bring their toes up as much during the leg’s swing phase, resulting in a larger ankle angle and shorter stride length, possibly because they tended to grip the flip-flops with their toes.
AU researchers also noted that flip-flops can be worn to provide short-term benefits such as helping beach-goers avoid sandy shoes or giving athletes post-game relief from their athletic shoes, but are not designed to properly support the foot and ankle during all-day wear, and, like athletics shoes, should be replaced every three to four months.
So if you have foot problems, ankle problems, lower leg problems and you do wear flip-flops a lot, perhaps limit the time you do spend in them. Some flip-flops on the market may provide more support, but are usually more expensive. For someone with lower-leg or foot problems, you should choose a flip-flop with more built-in arch support. Maybe even try those good old Dr. Scholl’s exercise sandals.