Give yourself a pat on the butt for all the hard work your butt does on a daily basis. Besides providing a cushiony seat wherever you go, your butt muscles are responsible for pretty much every movement you do.
When people talk about butt muscles, they're referring to your gluteus maximus, gluteus medius, and gluteus minimus — together they are "the glutes." "Your gluteus maximus is the largest muscle in the human body, and capable of being the most powerful," says Morit Summers, NCSA certified personal trainer.
Everyone's butt is different, and size doesn't necessarily correlate to strength, says Michele Burmaster, trainer and president of Body Positive Fitness Alliance. "Fat and strong muscle can live harmoniously among one another all over the body — including the butt," she says. And while exercise and strength can change the way someone's butt looks, genetics play a huge role in how your own booty looks, Summers says.
If you aren't sure how your own glutes stack up in terms of strength, Summers and Burmaster both suggest trying a glute bridge: Lie on your back with your legs bent, feet flat on the floor. Squeeze your butt and push your hips up so your body forms a diagonal line from your knees to your chest. Time yourself and see how long you can hold it to get an idea of your baseline strength, Burmaster says. "Your time and comfort level and even your mobility in this position should increase the stronger your glutes get," she says. Here are some of the reasons why strong glutes matter — that have nothing to do with the way they look:
They keep you upright.
You know those toy dolls that collapse when you press a button? That's pretty much you without your glutes. Your glutes are the reason why you can stand up, Summers says. The muscles in your butt work in tandem with your core to help stabilize and support your spine while you sit, stand, and move, Burmaster adds.
They help you move.
Glutes also are the reason you can walk and run, and just generally do any other kind of movement, Burmaster says. "They are responsible for initiation and acceleration of movement and rotation and stabilization of the hips," she says. You can think about your glutes as the connection between your upper and lower body — they help keep your back and core stabilized, and they're responsible for propelling your legs and body when you move. And this isn't just one of those things that runners or serious athletes have to worry about; strong glutes can help with every type of movement (even just sitting and standing).
They keep your knees stable.
Your knee is just a joint, and it needs all of the surrounding muscles for it to work properly (and not hurt), Summers explains. "The muscles around any joint can either cause or inhibit pain, and having strong glutes and a proper quad-to-hamstring ratio will help to keep the knee happy and healthy," she says. Strong, functioning glutes also keep everything in proper alignment, because they work with your hips to keep everything in neutral rotation, Burmaster says. Weaker glutes, on the other hand, could cause your knee to accidentally rotate when you walk, in a way that could easily cause torn ligaments, she says. "Knee injuries are the absolute worst to recover from, and having strong glutes is an easy way to prevent them."
They prevent back pain.
Your entire back — from your neck to your tailbone — rests and relies on your glutes, Burmaster says. The stronger your glutes, the easier it is for the rest of those muscles in your back to work, and the less pain you'll feel. "Deliberate glute work and generally good lower body work can provide ongoing relief to back pain," she says.
Summers says there's something called "glute amnesia," which is a term for people whose glute muscles just don't fire, usually from sitting too much. "The glute muscles become over-stretched and under-active, while the hip flexor muscles become overactive and really tight," she says. This is one main cause of lower back pain, and Burmaster says if that sounds like you, you should see a physical therapist, who can figure out where else you might have muscular imbalances (like overly tight hips or super-weak hamstrings) in addition to weaker glutes.
Bottom line: Any butt can be a strong butt, and there are so many reasons why you should care beyond aesthetics.