Habitual high-heel wearers, your attention, please. You know that feeling you get when you first slip off those impossibly high stilettos (the feeling after relief)? That tightness in your Achilles' tendons as feet assume a natural position, with heels on the floor? Researchers think they may know the reason for that.
A new study in the Journal of Experimental Biology tried to determine why women feel that tautness in the backs of their ankles after wearing high heels for long periods of time. Researchers focused on 11 women who were regular high-heel wearers, and a control group of nine women whose footwear consisted of flats.
The women's calf muscle size was measured via MRI, but no differences were noted, although researchers thought that might be the culprit.
"We were expecting slightly smaller muscle volumes in the high-heel wearers because we thought that if the muscle is in a shortened position then you are loading it less and the muscle volume should be smaller," one of the study's authors, Marco Narici of Manchester Metropolitan University in the United Kingdom, said in a news release.
Instead, ultrasound tests found that the muscle fiber length in the high-heel wearers was 13 percent shorter than in the control group. MRI scans also revealed that the Achilles' tendons in the high-heel-wearing women were thicker and stiffer than in the flats wearers. That may have compensated for the shortened muscle fibers while allowing calf muscles to function at their best while walking. Yet this thickening also caused some pain when the women changed from high heels to walking on flat feet.
Narici says he doesn't think women need to give up their sky-high heels (OK, you can exhale now), but he does recommend some stretching exercises to avoid those aches.