The case of the missing buttocks – it’s not all mum bum

Any casual observer, seated on a park bench, watching people walk by, might begin to ask: where did all the buttocks go? Why are our cabooses so often so flat?

It seems that the gluteus muscles, the biggest in the human body, have gone into hiding. They’re the source of our forward propulsion in walking and upward propulsion in jumping. Do we not walk and jump anymore?

Some call the widespread disappearance of buttocks  a case of “mum bum,” the phenomenon in which a woman gains a child but loses her bootie.

Yes, mum bum is a real thing. Google will bring you 2.6 million matches in less than three seconds. And there you can explore the gripping question: did Pippa Middleton lose her famous derriere to childbirth?

But what about dads? What about people of any gender who have never grown a baby? It’s not just women pushing strollers who sag.

Should we all be at the gym doing squats? Or in a vigorous yoga class, holding bridge pose for an eternity, preferably with one leg up in the air?

Not necessarily. What we really need to do is change the way we stand.

Don’t take my word for it. Two experts in mum bum, Kim Vopni, the Vancouver-based “Fitness Doula” and Denise Chiriboga at Strong Mom, both put the blame squarely where it belongs: pelvis forward posture.

In our culture, carrying the pelvis forward of the line of gravity is the norm.

So, when pregnant women begin to feel the weight of a growing baby, they lean back to balance it. By the end of the pregnancy, the baby may be gone, but the buttocks remain tucked under and gripped, and pregnancy posture is the new normal.

But what about those of us who haven’t been pregnant? As children, we start to take our pelvis forward to imitate the adults around us. Depending on our body awareness, and what our parents looked like, the result will be a moderately flat bottom, or none at all. The typical man stance, feet wide, knees locked, pelvis forward and chest lifted, plays havoc with every joint and muscle in the body – and it removes the possibility of a shapely butt.

First, because the pelvic floor muscles attach to the bottom of the tailbone. When the tailbone moves down and under, the pelvic floor muscles are no longer in their optimal placement, so they weaken.

Second, because when we tuck the buttock muscles, we stop using them for walking, and start using our hip flexors instead. This not only leads to tight, stressed hip flexors, it deprives our glutes of the work they need.

And third, when our pelvic structures move forward, something else has to lean back to balance it. That would be your upper back. Over time, this posture hardens into a pronounced thoracic curve, with the neck poked forward, bringing a cascade of ills from neck and shoulder pain to increased risk of osteoporosis.

Yes, you could go to the gym and focus on working your glutes. But there’s a more effective way to make the change. Take a tip from Denise at Strong Mom, who suggests taking a selfie from the side in a full-length mirror. Notice how far forward your hips are, and move your pelvis back until your weight is in your heels.

Then stay that way for the rest of your life. Every step you take, every stair you climb, will re-build your buttocks and make you stronger.

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