20170807_me_flattening_the_mummy_tummy_with_one_exercise_10_minutes_a_day.mp3

I admit it. I have a "mummy tummy," also known as "mommy pooch." You know, that soft, jelly belly you retain after having a baby — it makes you look a few months pregnant.

I've tried to convince myself that the pooch is a valiant badge of motherhood, but who am I kidding? The pooch bothers me. And it turns out it's been causing me back pain.

So when I hear that a fitness coach and doctor have come up with a technique that can flatten the pooch quickly and easily, I think, "Why not?"

A few weeks, later I'm rolling out a yoga mat with a dozen other moms and pregnant women in San Francisco.

"We will see a dramatic change," says Leah Keller, who leads the class. "You can easily expect to see 2 inches off your waist in three weeks of time," Keller says. "That's not an unrealistic expectation."

Decked out in purple yoga pants and leather cowboy boots, Keller is a personal trainer from New York City. She has developed an exercise that allegedly shrinks the mommy pooch.

There's science to back up the method, she says.

"A doctor at Weill Cornell and I did a study on the exact same program we're going to do," Keller says. "And we found 100 percent of women achieved full resolution."

OK! Wait a second. Two inches off my belly in three weeks? That sounds too good to be true. I decide to do a little digging into the science of mummy tummy and Keller's claim.

Putting the six-pack back together

It turns out the jelly belly actually has a medical term: diastasis recti, which refers to a separation of the abdominal muscles.

And it's quite common. Last year, a study from Norway reported about a third of moms end up with diastasis recti a year after giving birth.

"This is such a ubiquitous issue," says Dr. Geeta Sharma, an OB-GYN at Weill Cornell Medical Center-New York Presbyterian Hospital.

And it's not just a cosmetic problem. Diastasis recti can cause another big issue for new moms: lower back pain.

"People can start feeling some back pain because the core is weakened," Sharma says.

Diastasis recti arises during pregnancy because the growing fetus pushes the abdominal muscles apart — specifically the rectus abdominal muscles.

"These are the muscles that give you a 'six pack,' " says Dr. Linda Brubaker, an OB-GYN at the University of California, San Diego. "People think these muscles go horizontal across the belly. But they actually go vertical from head to toe."

The rectus abdominal muscles should be right next to each other, on either side of the belly button, Brubaker says. "There shouldn't be much of gap between them."

But during pregnancy a gap opens up between the muscles, right around the belly button. Sometimes that gap closes on its own, but other times it stays open.

That leaves a spot in the belly where there's very little muscle to hold in your stomach and other organs, a spot that can be one to two inches wide. That lets the organs and overlying tissue bulge out — and cause mommy pooch.

To flatten the area, women have to get those abdominal muscles to realign. And that's where the exercises come into play.

If you search online for ways to fix diastasis recti, you'll turn up a deluge of exercise routines, all claiming to help coax the abdominal muscles back together.

But the quality of much of that information isn't good, Brubaker says. "Some of it is actually potentially harmful."

Even some exercises aimed at strengthening the abdomen can exacerbate diastasis recti, says Keller, including simple crunches.

"You have to be very careful," she says. "For example, please don't ever again in your life do crossover crunches or bicycle crunches. They splay your abs apart in so many ways."

That said, there are a few exercise programs for diastasis recti that many doctors and physical therapists support. These include the Tupler Technique, Keller's Dia Method and the MuTu System in the U.K.

Most such courses, taught once a week for an hour in New York, San Francisco and at least a few other places, tend to run about four to 12 weeks and cost around $100 to $300. Some places offer online classes and videos.

The American College of Obstetricians and Gynecologists also recommends abdominal exercises for the perinatal period. But the organization's guidelines don't provide details — such which exercises work best, or how often women should do them and for how long.

Plus, ACOG focuses more on preventing diastasis than fixing the problem; it recommends strengthening the abdomen before and during pregnancy.

"The best way is prevention," says Dr. Raul Artal, an OB-GYN at St. Louis University, who helped ACOG write its exercise guidelines for the perinatal period. "The best way to do that is to exercise during pregnancy."

But, as Sharma, the Cornell OB-GYN, points out, no one has really vigorously studied these various exercises to see if they actually fix diastasis recti.

"There's a general knowledge that exercise is going to help," Sharma says. "But no one has really tested them in a standardized way."

Sharma hopes to change that. A few years ago, she teamed up with Keller to start to gather some evidence on her technique.

"We did a pilot study to see if the method is helpful for women," Sharma says.

The study was small — just 63 women. But the results were quite promising. After 12 weeks of doing Keller's exercise — 10 minutes a day — all the women had fixed their diastasis recti, Sharma and Keller reported at ACOG's annual meeting few years ago.

"We had patients that were even one year out from giving birth, and they still had such great benefit from the exercises," Sharma says. "We love to see that there is something we can do to help women."

Tight and tighter

Back at the class in San Francisco, Keller is taking us moms through the key exercise. It's surprisingly simple to do.

"The exercise is a very small, very intense movement. That's almost imperceptible," Keller says. "OK. We're going to do another set."

Sitting on the floor cross-legged, with our hands on our bellies, we all take a big breath. "Let the belly fully expand," Keller says.

And then as we exhale, we suck in our belly muscles — as far back as they'll go, toward the spine. "Now we're going to stay here near the spine. Hold this position," she says.

Then we take tiny breaths. With each exhale, we push our stomachs back further and further.

"Tight, tighter," Keller chants, rhythmically. "Good!"

This is our fourth week of class, and we've been doing this same exercise on our own every day for at least 10 minutes. So it's judgement day. Time to see if we've flattened our bellies.

Keller pulls out a measuring tape and starts wrapping it around women's middles.

One by one, there's success after success. Several moms completely closed up their abdominal separations. Many lost inches from their bellies.

One woman had amazing results. "Oh my goodness, you lost nearly four inches from your belly circumference," Keller exclaims. "That's amazing!"

How did I fare? Well, after three weeks, I didn't completely close up the abdominal separation. But I did drop more than an inch from my belly circumference.

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