Grandmother Pat LaColla, 82, was lured by the hype—”get in shape without setting foot in a gym”—when she bought a pair of Skechers last year, wincing at the $100 price tag. Toning shoes like those she bought are the newest craze in athletic footwear, projected to grow 500 percent to become a $1.5 billion market this year.

Although the designs vary, toners typically have strongly curved, thickened soles. From the moment Pat laced them up, she began to feel off-balance and was afraid she’d take a tumble. Going down stairs was terrifying, even when gripping the banister, and she tried going to the store once and didn’t dare leave the house again in them. “I was reeling back and forth so badly, I was sure I’d take a fall,” she said.

It’s not just the elderly who are having problems. Kara Lombardo, a 35-year-old orthopedic physician’s assistant, says she suffered from two days of lower-back pain after wearing Skechers in the operating room all day. The busy mother of a toddler liked the idea of working out while on the job, but knew she had made a mistake by her second patient of the day. “I also noticed that when I walked fast, my toes kept getting caught,” she said. “I nearly fell several times.”I recently spent a weekend in Skechers Shape-Ups myself after John Santa, M.D., director of the Consumer Reports Health Ratings Center, challenged me to the task after he tried them. The sneakers are part of a line in footwear that promises big changes just by walking in them. Among their offerings and their claims:

I’ve been known to take a few shoe-related risks in my life: wedges that wobbled, sandals that squeezed, and pumps that pinched so tightly that they reshaped my toes. But nothing quite prepared me for my 48 hours with Skechers, an experience like walking on a flimsy suspension bridge.

After failing to get used to them, I went back to regular sneakers. Pat LaColla eventually gave up and Kara Lombardo went back to regular sneakers as well. If it were up to me, the shoes would be sold in a store’s exercise equipment department–not in the shoe department—because they should be worn at most for a couple of hours to supplement your exercise routine, not for an entire day.

Given Pat and Kara’s experiences, toning shoes are not advisable—for any duration—for those with balance issues and nerve damage in the feet. And it looks like wearers who believe that they’re getting a good workout may be in for a surprise. Just last month, the American Council on Exercise enlisted a team of exercise scientists to test the effectiveness of toning shoes and found that none of them showed statistically significant increases in either exercise response or muscle activation during any of its treadmill trials. The trials each involved 12 physically active subjects.

It concluded that “there is simply no evidence to support the claims that these shoes will help wearers exercise more intensely, burn more calories, or improve muscle strength and tone.” And they raised the concern that “extended use of these toning shoes may alter the walking gait mechanics of wearers.” More testing is clearly needed to check their safety.

Orly Avitzur is medical adviser at Consumer Reports and blogs at the Consumer Reports Health Blog.

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