Butt selfies might still be over social media, but building strong, healthy glutes is important for way more than aesthetics. They’re really the powerhouse of your lower body—and key for proper everyday movement, balance, posture, and more. 

“Strong glutes play a very important role in stabilizing and controlling the hips,” says Lauren Powell, C.S.C.S., a performance coach for the training app Future. “Think of them as the strong base for the majority of your movement.” Your glutes power all sorts of basic activities and exercises, from walking and running to jumping, lifting, and even getting in and out of a sitting position. 

And, building glute strength benefits you for years to come. “Strong glutes are beneficial for balance, which can become more challenging with age,” Powell warns. Maintaining this balance is increasingly important in those later years, when concerns about bone mass and strength, as well as accidents, fractures, and falls arise. 

So, is your booty as strong as you think? Look out for the following signs that you have weak glutes—and use these trainer tips to start building strength, stat.

3 Signs of Weak Glutes

If your butt strength needs a boost, your body will clue you in—just perhaps not in the ways you might think. Here are three common signs. 

1. Low Back Pain

According to Powell, weak glutes force your body to rely on other muscles for movement, which puts stress elsewhere on the body and can lead to aches and pains—in many cases, in the lower back. “Low back pain can begin as subtle soreness or tenderness in the muscles of the lower back,” she says. “This commonly means that the hip flexors are working harder than necessary to compensate for the lack of glute strength.” (Yep, your hip flexors actually originate in your lower back and then wrap around and down the front of your hips, hence why stressing them out leaves you with an achy back.)

2. Knee Pain

Compensation can also affect the knees, especially in athletes, who complete high volumes of training. “If glutes are weak, the quadriceps muscle group can also be forced to take on some of that additional work, and over-contraction or engagement of the quads, along with the inability to relax them, can lead to increased tension on your knees,” Powell explains. 

3. Pelvic Tilt

Another sign of weak glutes is the dreaded but oh-so-common pelvic tilt. Ideally, your pelvis can tilt freely but rest in a neutral position. “The pelvis should be able to move, however when someone has weak glutes, it is common to see a greater anterior or posterior pelvic tilt,” Powell says. In an anterior pelvic tilt, the pelvis is rotated forward, creating an excessive arch in the lower back. The opposite occurs in a posterior tilt, in which the tailbone tucks way under. Since your glutes are charged with stabilizing your pelvis, these less-than-ideal pelvic positions pop up when your booty muscles can’t quite get the job done.

How To Build Stronger Glutes

If you’ve realized your glutes need some love, don’t panic. There’s plenty you can do to build those bad boys up.

1. Include Glute Activations In Your Warm-Up

“Many people find it beneficial to use ‘activation’ exercises at the beginning of their workouts to begin feeling the glutes working,” Powell suggests. “Some examples of exercises to include here are clamshells, hip lifts, glute bridges, squats, monster walks, lateral walks, and sumo squats.” You can perform these with just your body weight or add a miniband to increase the resistance.

Read More: 5 Squat Form Mistakes You Might Be Making—And How To Fix Them

While glute activations don’t directly build strength, they do help you warm up for exercises that will, making bigger lifts like squats and deadlifts more effective, according to Powell. They also help you feel more connected to your glute muscles so you can better focus in on them during other movements. 

Ideally, you’ll spend five to 10 minutes on these activation exercises and move through two to three sets of 10 to 15 reps of a handful of them. 

2. Lift Heavy

For the big compound moves you likely do on leg day (think deadlifts, squats, glute bridges, split squats, and lunges), using enough weight is a must for strengthening your glutes, according to Powell. Once you’ve mastered the bodyweight versions of these exercises, start incorporating external loads, like dumbbells, kettlebells, or a barbell.

For optimal strength gains, stick with a lower volume (that means fewer sets and reps) with a heavier weight. Three to five sets of three to 10 repetitions each is a good ballpark, Powell notes. When you can get through all the reps in a set with some gas left in the tank, it’s time to up your weights. This ensures you’re continually stimulating the muscles enough to trigger the greatest adaptation, and strength gains, possible.

3. Add Isolation Glute Work To Leg Day

If building your booty is a top priority, incorporate some isolated glute training to your lower-body days as accessory movements, in addition to those foundational lifts mentioned above, says Powell. Many of the exercises you incorporate during your warm-up can work well here, as do lateral lunges and step-ups. 

Read More: 7 Scientifically-Proven Benefits Of Strength Training

“Glute accessory work can be included at any point in the workout, but you do not want your accessory work to take away from your main focus of the day,” Powell says. So, incorporate these moves after the big guns. Go for three to four sets of 12 to 20 reps.

4. Squat With A Miniband To Boost Engagement

Want to make sure you’re reaping maximum glute benefits from squats? Make this simple tweak: Loop a miniband around your legs, positioned just above your knees, and get to it. 

The perk of this little band: It acts as resistance against the outsides of your legs. “Keep your knees driving out [against the band] and don’t allow them to collapse in,” Powell says. Since you have to engage your glutes in order to drive outwards against the band, this tweak is a surefire way to ensure your muscles are fired up.