Flat when lying down, protruding when standing? — This is what leading physiotherapists now recommend for “mummy tummy” (and it isn’t sit-ups)

Summary: An experienced physiotherapist explains why traditional abdominal training after childbirth does not work — and which single movement actually activates the deep muscles that keep your midsection in place. What most women have been doing wrong for years, and how ten minutes a day can make the difference.

Martin H., physiotherapist specializing in postnatal recovery, at his practice in the Oslo area.

1“Every week, there are women sitting with me who have been training incorrectly for years”

Martin H. opens the door to his treatment room at a physiotherapy practice in the Oslo area. On the wall hangs a sketch of a woman’s abdominal silhouette — before and after childbirth. Next to it are the keywords: Pelvic floor. Deep musculature. Lifting effect. It is 9 a.m., and his first appointment is a 36-year-old mother of two. Her concern: a belly that has not gone away in three and a half years.

“You could almost tell me exactly the same story as the patient before her and the one after,” says Martin. “Two years of Pilates. Crunches morning and evening. Three diets. Jogging in the summer. And today, her belly looks almost the same as it did six weeks after giving birth.”

Martin has worked as a physiotherapist specializing in postnatal recovery for over twelve years. During that time, he has treated more than 3,000 women — and he openly says that most come into his practice frustrated. Not because they have done too little. But because they have done the wrong things.

“The truly tragic thing,” he says, pouring himself a cup of tea, “is that these women are disciplined. They are fit. They eat sensibly. But they are fighting a belly that has nothing to do with discipline or diet. It is an anatomical problem. And the more classic abdominal exercises they do, the worse it gets.”

2Why sit-ups, crunches, and jogging make your belly worse

Search for “belly after pregnancy,” and you mainly get three recommendations: eat less, do more sit-ups, and do more cardio. Martin smirks when I mention it.

“That is exactly the trinity that reinforces the problem,” he says. “Sit-ups and crunches work the superficial abdominal muscles. We need them, absolutely. But they are not the problem. The problem lies underneath.”

He draws a quick sketch on the whiteboard. A silhouette of the pelvis, viewed from the side. “In most women, the pelvis slowly tilts forward after pregnancy. It is a completely natural process — the baby’s weight over nine months, softened ligaments, and often lying on the stomach while breastfeeding. But when the pelvis remains in this forward tilt, the deep muscles lose their hold, and the lower abdomen is pushed forward.”

This, he says, is precisely why almost all patients describe the same symptom: When you lie down, your stomach looks normal. When you stand, it bulges outward. And sitting, with your shoulders slightly hunched, you look as if you are in your fifth month of pregnancy all over again.

“If you do sit-ups now, each repetition increases the pressure forward and downward. Exactly the direction we actually want to relieve. Jogging is even more insidious — every step delivers a downward shock that further stretches the pelvic floor and deep muscles.”

Most women come to me because their stomach remains despite exercising. My job is usually not to give them more exercises — but to explain why they are allowed to stop doing what they are doing.

It sounds almost paradoxical. But once you understand what is actually happening beneath the abdominal wall, the logic is simple.

3What the deep muscles are — and why they are the key

The abdominal muscles everyone knows are the superficial layer — the rectus abdominis and the oblique abdominal muscles. They are what form a “six-pack” when they become visible. But they do not hold the stomach in place.

“That’s what the deep layer does,” says Martin. “Above all, the transversus abdominis — a kind of inner corset muscle that runs transversely around the midsection. And the pelvic floor. Together they form what we in physiotherapy call ‘the deep core.’ This layer keeps the stomach flat. Even when you stand. Even after three cups of coffee in the afternoon.”

During pregnancy, the transversus is stretched to several times its original length. After childbirth, it does not automatically contract again. For some, this happens spontaneously during the first few months. For very many — and that is the majority — the muscle remains weak and stretched. The result: the midsection lacks the inner corset that holds it in.

“And now comes the crucial part,” says Martin, leaning forward. “You simply can’t reach the transversus with sit-ups. It lies deeper. It responds to a completely different type of stimulus — slow, controlled tension against light resistance. Not short, hard movements.”

What he describes sounds fairly unspectacular to many women at first. No 200 crunches. No beads of sweat from HIIT. Instead: ten to fifteen minutes a day, sitting or lying down, a calm movement against resistance in which the lower back stays flat against the floor and the core contracts from within.

In physiotherapy, this type of exercise is called an “upward lifting movement.” The pelvis is gently corrected via the direction of the pull, and the deep muscles learn again to hold the midsection in place.

4Maria, 38: “After six weeks, the trousers that had been in the closet for three years fit”

Maria - the name has been changed at her request - came to Martin nine months ago. Mother of two, youngest child three and a half. Project manager by day, in good shape. Her problem: a stomach that had not gone back after her second birth. Yoga three times a week. Pilates classes during lunch. Half marathon nine months ago.

“She was in better physical shape than most of the women who come to me,” says Martin. “And yet an acquaintance asked her at the store if she was pregnant again. That was when she realized she needed a different strategy.”

Martin put her on a program with two components. First: no sit-ups, no jogging, no high-intensity cardio for now. Second: ten to fifteen minutes of targeted deep-muscle training every day with a pedal resistance band. The movement: lying or sitting, feet in the straps, handles pulled toward the chest, slow and controlled exhalation, stomach actively drawn inward. 25 repetitions, three times a week.

Maria wrote in her training diary in week three: “For the first time today, no protruding stomach when I stood up.” In week six: “Trousers that have been in the closet for three years fit again. Without dieting.” In week ten she sent Martin a short message: “I stood at the playground yesterday - and no one asked what month I was in.”

In twelve years of practice, I have received hundreds of messages like these. What changes is not just the stomach. It's the posture. The trousers. The look in the mirror.

Maria's story is not the exception. It is, Martin says, almost the rule - when women stop exercising incorrectly and start doing it right.

5The one movement that changes everything - in 10 minutes a day

What Martin explains to his patients can be distilled into one single core movement. It requires no studio, no trainer, no expensive equipment. It only requires a pedal resistance band, a space on the living room floor, and about ten minutes.

“Sit on the floor with your legs straight. Place the straps around your feet. Hold the handles in both hands. Slowly lean backward until your upper body is at approximately 45 degrees. Now comes the crucial part — pull the handles in a controlled manner toward your chest as you exhale, while actively drawing your stomach inward, as if you were trying to fasten an overly tight trouser button. Hold for two seconds. Then slowly return. 25 repetitions.”

What happens during this movement? Two things at once, says Martin. The pelvis tilts backward into the correct position through the pull. And the transversus, the deep corset muscle, is activated against the band's light resistance — precisely the kind of slow, controlled stimulus it responds to.

“If you do it correctly, you feel a clear activation throughout the entire lower abdomen. Not a burning sensation like after 50 sit-ups. More like a deep warmth, as if you were lifting something from within. Your lower back stays flat against the floor. That is important. If it arches up, it takes over the work — and then you lose the effect.”

Three times a week is enough for most women, says Martin. If you want to do it daily, that's fine too — the load is gentle on the joints, with no impact, no jumping, and no pressure on the pelvic floor. Many women see the first visible changes after four to six weeks. For some, it happens faster; for others, it takes longer. It depends on where you start and how consistently you exercise.

I tell my patients honestly: None of this is magic. It is simply the right exercise for the right muscle. But that is precisely what makes the difference.

6This is what I now recommend to my patients: Flexitrener

When we ask Martin which pedal band he specifically recommends, he hesitates for a moment. “I don't sell anything. But for about a year, I have been giving my patients the same recommendation to take home — and it's Flexitrener.”

The reason, he says, is quite simple. First: The band has six tensioned tubes instead of just two or three. This makes the resistance more stable and consistent throughout the entire movement. Second: The foot pedals are shaped so that the feet do not slip out — especially important during longer seated sessions, because many women would otherwise have to readjust after three repetitions. Third: The handles are ergonomic, with soft foam padding, and do not press into the palms even after 25 repetitions.

“It sounds like minor details. But if the equipment is uncomfortable, my patients stop using it after two weeks. Comfort determines whether you exercise three times a week — or not at all.”

Flexitrener is delivered in Norway with free shipping and a 30-day satisfaction guarantee. If you use it consistently for four to six weeks without noticing any change, you can send it back.

“That’s also the point where I can tell my patients: Try it. If it doesn’t work, you’ve lost nothing. If it works — and it does for the vast majority of women — then you have a tool you can use for the next ten years.”