Back or Knee Pain? Uh-Oh, You May Have ‘Dead Butt Syndrome’

Nov. 13, 2025 – You won’t find any support groups for dead butt syndrome, aka gluteal amnesia, sleepy glutes, flabby butt, longback, or, for King of the Hill fans, diminished gluteal syndrome.

“They all mean sort of the same thing: weak gluteal muscles,” said Dean Somerset, a clinical exercise physiologist based in Edmonton, Alberta, Canada, and co-author of Rock Solid Resilience.

If you guessed that small, weak, and poorly functioning glutes are often the result of too much sitting and too little exercise, you wouldn’t be wrong, according to Somerset.

Meanwhile, Los Angeles-based physical therapist Chad Waterbury, DPT, has seen it in healthy, fit, active clients, including a few professional athletes. “When we do exercises like squats, deadlifts, lunges, it’s very easy for other muscles to do the work you want the glutes to do,” Waterbury said

In both populations, the glutes stop doing what they should, and that can lead to serious problems up and down the movement chain. 

If misfiring glutes force the lower-back muscles to take on loads they’re not meant to handle, the result can be years of back pain. And if the glutes fail to perform their stabilizing role in exercise and sports, you could be looking at chronically sore knees, or perhaps even an ACL injury. 

That means the Venn diagram of dead butt sufferers includes people who sit a lot, active people, those with back pain, and those with knee pain. All those people, all that overlap, all those butts.

Is your butt among them?

Putting a Name to the Pain

Stuart McGill, PhD, coined the term “gluteal amnesia” to describe what happens when pain causes people to change how they move.

“In people with longer-term pain, the pattern of nerve pulses distributed to the muscles can become corrupted,” he explained. “The pain kicks off an inhibition pathway, so the brain finds a different way to do the same basic thing.” 

That, in turn, changes the way muscles like the hamstrings contribute to the movement.

“But even when the pain has gone away, the brain often remembers the painful pattern,” McGill said. Which means it also forgets how to use the muscles appropriately and efficiently. 

McGill, a distinguished professor emeritus at the University of Waterloo and author of Back Mechanic, showed how the process works in a 2013 study. In that paper, he and his co-authors used “gluteal amnesia” and “gluteal inhibition” interchangeably. 

The latter term is probably more appropriate, given that some people hear the former and think it implies gluteal dementia, as if the misplaced movement patterns can never be restored.

Fortunately for the gluteally deficient among us, they can. Just not in the way most of us would assume. 

Hips, Femur, Knees, and Woes

While McGill was teasing out the connection between gluteal amnesia and back pain, Christopher Powers, PT, PhD, was looking at how abnormal glute activation patterns could lead to knee problems. 

“The gluteal muscles control the femur,” he explained. “The femur’s half the knee joint. So by definition, the gluteal muscles control half the knee.”

Powers is associate chair of the Division of Biokinesiology and Physical Therapy at the University of Southern California, where he studies the root causes of the lower-body injuries. And he addresses a lot of them with the athletes and patients he sees at the Movement Performance Institute in Los Angeles, which he founded and owns. 

His research has shown that a key function of the gluteal muscles is to prevent the femur from rolling inward during sports, exercise, or everyday physical activities. 

“Once you stop using the muscle, the brain kind of forgets about it,” Powers said. “You lose the neural connectivity.”

And if the brain forgets how to stabilize the femur, just about anything you do, from walking to landing after a jump, will put stress on your knee joints. 

How to Know if Your Butt is Dead or Dying

Remember, given that sedentary and active people have this issue, aside from chronic knee or back pain, you may not be able to tell if your glutes are firing properly or improperly. 

Waterbury recommends this self-test: the single-leg glute bridge. 

Lie on your back with one leg lifted out straight and the other leg bent at a 45-degree angle with the foot flat on the floor. Your thighs should be parallel. Raise your butt so your thighs and torso form a straight line. 

Hold that position for 20 seconds (or as long as you can up to 20), while paying close attention to which muscles you feel are working the hardest. Lower your hips and repeat with the other leg. 

If you felt the strongest contraction in your hamstrings or lower back, instead of your glutes, you need to improve your gluteal activation. Also, muscle imbalances are common, so it’s also not unusual for you to feel weaker in one glute or the other.

Two of Powers’s studies offer encouraging news for those whose glutes have lost their way. 

The first, published in 2016, found that a week of glute-activation exercises increased neural drive to the muscles. 

A follow-up, published in 2022, found that the same exercise protocol made the muscles more able to stabilize the femur.   

So let’s take a look at the program.

Wake Up, Dead Butt

Powers’s program includes just three exercises, all of which may look familiar: clamshell, side-lying hip abduction, and fire hydrant. 

Even if you haven’t used the exercises in your own routines, you’ve probably seen other people doing variations of them. 

Here’s the catch: To do the program correctly, you have to forget what you’ve done or seen. 

Instead of doing sets and reps, you’ll hold each position for up to a minute at a time. And you’ll need to do the program almost every day. 

“When you do reps – up and down, up and down – the focus tends to be on the movement,” Powers said. Isometric holds like these require something else: intense concentration on squeezing the muscle in one continuous position.

That extended muscle activation allows the brain to reopen its channels of communication. If you follow the isometric holds with exercises that use the glutes, like squats or step-ups, you reinforce those neural signals.

To get the most out of the exercises, you’ll want to use a miniband positioned around your thighs, just above your knees. When you can hold a position for a full minute, use a more challenging band the next time. 

Here’s a closer look at each exercise. 

Clamshell

Lie on your side with your legs together and your hips and knees bent 45 degrees. 

Lift your top knee straight up while keeping your feet in contact with each other. 

Feel the squeeze in your glutes and hold for up to a minute. Switch sides and repeat. 

Side-Lying Hip Abduction

 Lie on your side with your top leg straight and bottom leg bent at the knee about 45 degrees.

Lift your top leg up and slightly back.

Feel the squeeze in your glutes and hold for up to a minute. Switch sides and repeat.

Fire Hydrant

To Powers, the fire hydrant is the best of the activation exercises. “If I were to pick one, I’d take it over the other two,” he said.

But it’s also the trickiest one to get right, since you’re asking your glutes to perform three functions, as you’ll see: 

Kneel on all fours with your hips parallel to the floor and your hands shoulder-width apart.

Without shifting your hips, lift one leg up (hip abduction) and back (hip extension). Position your thigh so it’s neither perpendicular to your torso (straight out to the side) nor aligned with it (straight back), but instead about halfway between those two points. (It’s called “fire hydrant” because you’re mimicking a dog doing what a dog does to a fire hydrant.)

Now turn your thigh outward (external rotation) until you feel tension in the band. 

The goal isn’t to achieve any particular range of motion. It’s to reach a position you can hold while keeping your hips level with the floor.

Hold for up to a minute, switch sides, and repeat. 

Restoring Your Seat of Power

People in Powers’s studies did three isometric holds of each exercise, with each leg, twice a day for seven consecutive days. 

But Waterbury, who studied under Powers at USC, uses a streamlined version of the program with clients, athletes, and patients. 

Start with these exercises:

• Clamshell, 30 seconds per side
• Side-lying hip abduction, 30 seconds per side
• Fire hydrant, 30 seconds per side 

Do the exercises six days a week for four weeks, either on their own or as part of a warmup before a workout. “That’s plenty to get the glutes activated,” Waterbury said.

After four weeks, do the exercises three times a week, preferably before a strength workout that includes squats, deadlifts, lunges, or other movements that use your glutes in coordinated action with other lower-body muscles. 

You can also do more advanced versions of the exercises, as Waterbury demonstrated in this video.

What matters most, he emphasized, is that you make these isometric holds a permanent part of your fitness routine.

“Too many things we do throughout the day make your glutes want to shut down again,” he said. 

Ultimately – and this is pretty good life wisdom – it’s a lot easier to keep your butt alive and well than it is to bring it back from the dead.