Motor Control During and After Pregnancy

Many of the structural changes during pregnancy are obvious (um, like your belly). Others, like your shoe size, are less obvious. All of these structural changes, little or big, affect the way your muscles fire in order for you to function. The way your muscles fire, including the firing order and the strength of the contraction, is known as motor control. Sometimes people call motor control “movement patterns.”

Sometimes movement patterns can become habit, and those habits can last even after your body returns to its structural “normal.” Those habits can lead to difficulties with daily function (anything from staying leak-free to lifting the stroller in the trunk of your car), increase your risk for injury, and result in less than optimal athletic performance. For those reasons, it’s important to restore your movement patterns as a part of your post-pregnancy recovery plan.

Here’s the skinny on those movement patterns. Most affected is your core.

We tend to think of our core as a slab of muscle that needs to be tightened back down to its normal size after pregnancy. If it’s strong enough, it will both work well and look good, right? No. For both. Your core has to fire correctly, with the muscles turning on and off in the right order with the right amount of force for every movement you make throughout the day. And your core isn’t just one deep muscle – it’s made up of 4 muscles (or groups of muscle) and if one isn’t working like it should, you’re trying to bounce a deflated basketball. Just strengthening the muscles of your core in isolation simply won’t do the trick.

How Your Core Should Work:

Here’s how it should work. Making up your core, you’ve got your diaphragm, your pelvic floor, your abdominal muscles, and your back muscles. Your diaphragm is a parachute-shaped muscle that separates your abdominal cavity from your chest cavity. When your diaphragm contracts, it moves down, opening up your chest cavity so that air can fill your lungs and increasing the pressure in your abdomen. That increased pressure in your abdomen in that moment provides stability for your trunk and unloads your spine. When you breathe out, the reverse happens: the pressure in your abdomen decreases and the air exits your lungs.1

Pelvic Floor

Deep Abs and Back Muscles

Outer Abs

After Pregnancy:

To help demonstrate why that needs to be fixed, here’s how that plays out. When you have lost the link between your pelvic floor and your TrA, your body skips over the pelvic floor contraction as you exhale, going right to the TrA and multifidi contraction. But those contractions are weak, disorganized contractions. Then you continue on, firing the outer abdominal muscles, then moving your arm or leg, firing the outer abdominal muscles more in response to the arm or leg movement and then, finally, at long last you’ll have a late, really strong contraction of your pelvic floor.2,7 It fires really hard to make up for being so late, but often it may be a day late and a dollar short if you’re prone to leaking, especially if that arm or leg movement was lifting a heavy stroller into the trunk of your car. Or maybe trying to do so while laughing.

 

Core Motor Control Before & After Pregnancy:

 

This pattern needs to get fixed. That disorganized TrA contraction means you’re missing out on thousands of times a day when you could be getting a high quality, functional core contraction. If you’re doing planks and wondering why they’re not helping, this is why. Planks in your workout don’t hold a candle to missing out on thousands of contractions a day that should happen naturally. Don’t get me wrong, keep working on your planks, but work on your firing pattern too. If you’re working on your Kegels and you know your pelvic floor is strong, but you’re still experiencing leaks or accidents, it could be a firing pattern issue. If you just don’t perform athletically the way you want, it could be because you aren’t getting those core muscles to fire the way they ought to. It’s like the difference between doing a push up on a BOSU ball versus on firm ground. You just won’t have as much power without a stable base.

Other Movement Patterns:

Other movement patterns affected by pregnancy include the way you walk. When you’re pregnant, you rely more on your outer hip muscles (gluteus medius) instead of your butt muscles (gluteus maximus), and your steps are shorter and wider.8 It’s helpful to strengthen both your gluteus medius and your gluteus maximus while your body returns to its structural baseline to prevent injuries and optimize their recovery as your gait returns to normal. You also have a lot of smaller hip muscles that control the rotation of your hip joint that were pulling at a different angle while you were pregnant, and as they heal it will help to strengthen those muscles along their line of pull.

 

In this program, we’ll get to work right away with the video series titled “The Basics” fixing that core movement pattern. We’ll also work on those smaller hip muscles and your gluteus maximus and medius along their lines of pull. No matter what your fitness level coming out of pregnancy, it’s important not to ignore those smaller muscles and the movement patterns we’re restoring – our bodies are smart and have the tendency to focus on the big muscle movement to get a job done at the expense of the smaller muscles that are trying to make a comeback.

References:

1. Hodges PW, Butler JE, McKenzie DK. Contraction of the human diaphragm during rapid postural adjustments. The Journal of Physiology. 1997;505(2):539-548.
2. Smith MD, Coppieters MW, Hodges PW. Postural activity of the pelvic floor muscles is delayed during rapid arm movements in women with stress urinary incontinence. International Urogynecology Journal. 2007;18:901-911.
3. Hodges PW, Sapsford R. Postural and respiratory functions of the pelvic floor muscles. Neurourology and Urodynamics. 2007;26:362-371.
4. Hodges PW, Richardson CA. Feedforward contraction of transversus abdominis is not influenced by the direction of arm movement. 1997;113:362-370.
5. Junginger B, Baessler K, Sapsford R. Effect of abdominal and pelvic floor tasks on muscle activity, abdominal pressure and bladder neck. International Urogynecology Journal. 2010;21:69-77.
6. Pereira LC, Botelho S, Marques J. Are transversus abdominis/oblique internal and pelvic floor muscles coactivated during pregnancy and postpartum? Neurourology and Urodynamics. 2013;32(5):416-419.
7. Madill S. Differences in pelvic floor muscle activation and functional output between women with and without stress urinary incontinence. September 2009.
8. Foti T, Davids JR, Bagley A. A Biomechanical Analysis of Gait During Pregnancy. The Journal of Bone & Joint Surgery. 2000;82(5):625-632.