Is minimalist footwear better for your pelvic floor? Maybe.
As we like to say in the PT world, it depends.
There are so many types of running shoes these days, from minimalist to maximalist, with a lot in between. What nobody tells you is that the kind of shoe you run in can impact your running form. Now, there’s not one specific shoe that is going to make you run with perfect form, but there are shoe characteristics that promote a more efficient gait.
Remember, the most important equipment is the engine...you...but there are things you can do to decrease your risk of injury and become more efficient while you run. This is important when you are returning to run postpartum because your body is recovering from childbirth. You want to slowly reintroduce running to your body, while also decreasing the risk of injury by optimizing your running form.
Let’s start with the two most important things (in my opinion) to think about when returning to run postpartum:
Minimizing the load on your body (this includes your pelvic floor)
landing with your foot under your center of mass, which means under your body with a slightly bent knee
Runners need good shock attenuation, or minimizing the cumulative force from repetitive landing on the ground. You want a shoe that will allow you to know you’re landing lightly. A high cushion shoe can actually mask the fact that you are landing heavy (think Hoka). A heavier landing results in increased force through your body, and over time, higher repetitive load and risk for injury.
There are a couple ways to find out if you are landing heavy while running:
First, take out your ear buds and listed to your foot as it hits the ground or treadmill. Is it loud? Relatively quiet? Slapping? Do both side sound the same? Or, you might have no idea because there is so much cushioning in your shoes that it sounds soft but really isn't.
Second, start running on the treadmill and listen to yourself run, then take of your shoes and run for 30-60 seconds without them. Did you start running heavy then switch to a lighter more quiet footfall? Most people do this automatically, but not everyone. Some people naturally run lightly, some people continue to hit the ground really hard. If you are still running heavy then try to run more quietly, and if this is hard then you know you need to practice! If you can't land softly without shoes then you are almost definitely hitting too hard with shoes on.
If you LEAK when you run or have a PROLAPSE this is an excellent exercise to try! Run to the point at which you start to leak or feel symptoms, then take off your shoes and try running quietly for 30-60s (you might land on your midfoot or forefoot to accomplish this and that’s ok, just don’t land heavy on your heel). Are you still leaking? Still feeling that heavy sensation or discomfort? If not, then switching to a midfoot or forefoot strike or a minimalist shoe might help, or at least learning to run more lightly to decrease the impact on your pelvic floor. In order to accomplish this from a shoes perspective, you basically want something that is flexible and allows you to react to the ground more naturally.
A shoe with a large cushioned heel (most running shoes) encourage what we call a “heel strike pattern,” or when your heel is the first thing to hit the ground when you land. If you have a big cushioned heel on your shoes, it forces you to land heel first with your foot out in front of your body, and often a straight knee. It makes it difficult to land on your midfoot or forefoot, and also makes it harder to land with your foot under your center of mass. Landing with your foot under your center of mass just means evenly under your body with a bent knee, and not stretched out in front. Excessive heel height and increased lateral flare of the shoe can increase foot pronation as well.
The way you hit the ground, your foot contact pattern, influences how you absorb energy. If you hit with your heel, your knee and hip do ~70% of the energy absorption, while your foot and ankle do ~30%. If you land on your forefoot, your knee does about 50% and your foot/ankle 50% (Powers unpublished data, MBRL). When you land on your heel out in front of your body, it increases your initial vertical loading rate (Larson et al, 2011). This means, the amount of force from hitting the ground (65-75 body-weights per second) goes through your body at a faster rate because of how you land, instead of being dissipated a little more efficiently when you land with your foot more underneath you. This increases your risk for injury, or inter terms of returning to run postpartum, a worse environment for a healing pelvic area. The rate at which you load your body is what matters. How you land can change that.
This is why a more minimalist type of shoe with less of a cushioned heel might help you land with your foot under your center of mass, instead of out in front, potentially promoting shock absorption through your foot/ankle/knee, which makes it easier to decrease your loading rate. This leads to less risk of running injuries, and I would argue a better environment for a healing pelvic floor or cesarean section to safely get back to running.
How does loading rate effect your postpartum body? Your pelvic floor?
During pregnancy as your baby grows, running kinematics change. This should seem obvious because your center of mass changes rapidly at the same time as your hormones are fluctuating causing laxity in your ligaments, destabilizing your pelvis (and everywhere else), all while gaining weight. So of course how you run is going to be affected.
It’s no wonder that the amount of excursion (in this case excessive movement) of your pelvis while running increases during pregnancy, because your body is unable to meet the demands of running in the same way. You need great pelvis control and core stability to maintain good form while running. So when your center of mass moves from having a baby bump, your pelvis becomes lax from all the hormones, you gain weight, and your abs stretch out (which makes them much less efficient), how the heck are you supposed to maintain good running form? Do you see where I’m going with this?
Now post-partum the only thing that has changed is that your center of mass is probably back to normal and you’ve lost some weight. But now you are likely more sleep deprived and have lost even more strength throughout the process of childbirth and having a newborn that sucks all of your spare energy.
You still have hormones causing laxity, weak abdominals, weak glutes, and now either a traumatized pelvic floor or a surgical scar from childbirth as well. Let’s add back pain to the list (mid AND lower) because you are feeding and holding your baby all the time and your posture sucks.
In a study of 244 women postpartum, 35% reported pain when returning to running.
Pelvis and trunk stability are important to control your body through multiple planes of movement during running. Did you know that 72% of women postpartum reporting pain with returning to run experience pelvis-hip-back pain versus only 20% of the general population?You might get low back pain, glute strain (hip pain), or ITB syndrome if you run and can’t support your body adequately.
If your low back hurts when you run, it could be because your hip abductors (glutes) aren’t strong enough so your spine responds with excessive movement. Couple that with postpartum hormones and you have an unstable pelvis, which means you need even more strength to stabilize it.
The good news is this is all fixable! With a little re-training (both strength training and what we PTs call neuromuscular training), you can get right back to where you want to be. Over time your body will heal naturally. Your muscles will respond to strength training, and your form will improve from correct practice.
This is where making the right choice in shoes can make a difference. You have the opportunity to really work on your running form when you transition back to running postpartum because you build up your mileage slowly. This allows you to adapt to new shoes that could help maximize your performance and help minimize the impact on your pelvic floor!
How to choose a running shoe
You want a running shoe that is light, flexible, has minimal to no heel-to-toe drop (zero drop), not too much cushioning, and most important: comfortable.
There are endless debates about the best kind of running shoes and how they impact biomechanics. I am clearly an advocate for more minimalist footwear, and there is plenty of research to support it, as long as the transition to a more minimalist shoe is slow and steady. However, you can read about how to select your running shoe based on your needs and shoe characteristics here!
Above: Characteristics of a good minimalist running shoe. (the Running Clinic)
We can't talk about running shoes without highlighting some of the most important aspects of your form. Without geeking out too much and going into a lot of details (that's for a later post;), you can work on your own running form by trying a couple things:
Maintain a high cadence (170-190 steps per minute)
Land with your foot under you body with a slightly bent knee (not out in front)
Don't change too much too quickly
Listen to how light or heavy your footfall is. Count the number of times your feet (both) hit the ground over 1 minute. Lean forward from your ankles and don't reach with your front foot as you land. All of these things are easier said than done, but can be accomplished with practice, patience, and consistency.
What shoe do I wear?
Over the last decade I've tried pretty much every brand of running shoe. I actually ran my first marathon in a Nike. Yep. I can't believe it either. Somehow they manage to make the worst running shoes now. Then I tried Brooks, which led me to their "Pure Project" shoes and my initial interest in minimalist running (also coinciding with the book Born to Run). I tried to switch to a barefoot Merrill shoe, but was marathon training at the time and couldn't commit to the change. From there I started wearing a brand of shoe called ON, which is what I ran my first Boston Marathon in (2015), and since then I've started to see that shoe all over the place! I actually still really like them, but they get rocks stuck in the bottom and they are too expensive. I also think some of their more recent shoes are too stiff.
My most recent shoe is made by Altra which has a zero drop, is light, and flexible with a wide toe box. I ran my last 2 marathons in the adult version of these, which they don't make anymore unfortunately. I'm always up for trying something new, so I just started running in this pair of Altras. So far they are more stiff through the cushioning than my last pair, but I'm not drawing any conclusions until I run a few more miles in them! I also like these made by Altra but haven't tried them yet!
When I first started running again postpartum I decided to fully transition to minimalist shoes. I used Vivobarefoot, similar to this pair and an older pair of New Balance Minimus shoes. The transition went great for a few weeks while I was in Arizona, then back in Boston it started snowing, and I couldn't get out for runs consistent enough during the day (and truth be told I was unmotivated to run in the freezing cold and dark! who else was in Boston this January? brutal.) However, I love these boots (tan and red version at right) to help keep my feet strong while I'm walking around all winter!
So you get to decide what shoes to wear, but now you understand how your shoe choice might effect your running form, and in turn your pelvic floor!!!
Life is short...buy the shoes!