Gluteal amnesia is no joke for runners. If you sit at a desk, you’re not immune.

Simply put: Our glutes give us power when we run. If they’re not firing at full capacity, we’re not as efficient as we could be. Sitting for long periods of time can tighten hip flexors and teach glutes to be lazy. And some runners may find they never fully activated their glutes in the first place.

As an attorney and relatively non-moving person for most of my mid-20s and into my 30s, my glutes were fairly useless when I began to run. I continued to not pay much attention to how I used them until injuries—like my tibia stress fracture, to name only one of the injuries I’ve dealt with over the years—began to plague me. It wasn’t until I first identified which muscles were not responding and began to work specifically towards recognizing their movements. Then, I began using this one simple mobility exercise on a regular basis to bring my butt back to life:

Laying face down on a firm surface (like the floor), with legs and arms extended, I would try and clinch my butt cheeks—but only clench one cheek at a time.

At first, nothing moved. Literally, no cheek movement whatsoever.

But little by little, the right cheek had a twitch. Then more. Then the left. And after a few days and weeks, I had complete control over which cheek moved and when, to the point where I could make them wiggle to the tune of Sir Mix-a-Lot.

Next, I moved on to strengthening. I started with leg lifts and lunges—just a few at a time to start, slowly building the number of reps and amount of time I spent on these exercises each day until I began transitioning into lifting heavier weights, squatting deeper and venturing into one-legged squats and more. This now-working rump is starting to pay massive dividends on the run. Now, I run with a smile, because my butt is also running with me.

Getting our glutes to work for (not against) us is not rocket science, but it does take some strange, focused work. Work that, as a beginner and adult onset athletes, that is worth the time, energy and sure—giggles and butt jokes as well.

Meredith Atwood (@SwimBikeMom) is motivational speaker, IRONMAN triathlete and author of Triathlon for the Every Woman: You Can Be a Triathlete. Yes. You.