If you're focused on your rearview, the glute extension-better known as hyperextension-is a top-tier glute exercise for strengthening and building the musculature of your butt. While many people turn to the obvious choices like Romanian deadlifts and hip thrust alternatives, glute extensions have one advantage they don't. When done with a full range of motion, this move can also help work a body part we're often afraid to train: the low back.
"As a fitness culture, and in society in general, we're afraid of spinal flexion," where the lower back is flexed into a C-shape, says Greg Pignataro, C.S.C.S., founder of Never Past Your Prime. "But it's a fundamental movement. It's something we do every day if we bend down to pick something up. And just like any other movement, it's something we can train to be strong in."
Below we'll break down how you can use glute extensions to increase your strength, prepare your glutes and hamstrings for more hip-hinging, and injury-proof your spine when doing heavy squats or deadlifts.
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What Is a Glute Extension aka Hyperextension?
The glute extension, or hyperextension, is an exercise that's performed on a back extension bench. This bench sits at 45 degrees, has two flat pads in front for the thighs, and two round pads closer to the floor for holding the lower legs in place.
The original use of the back extension bench was to perform a back extension-an exercise that helps strengthen your lower back and core muscles. When doing this move, the thighs are placed against the flat pads, and the backs of the lower legs are locked in by the round pads. The trainee bends at their hips-and eventually rounds their back-to fold in half as their head goes towards their feet and the floor. From the bottom, the back is extended to come back to the top.
When exercisers call this move a "glute extension," they're often using different strategies to help the back extension target the glutes more and work their backs less.
How to Set Up for a Glute Extension
Oftentimes a glute extension is done by arching the upper back throughout the movement, with the chin pressed against the chest. But Pignataro and Shawn Arent, Ph.D., C.S.C.S., chair of the Department of Exercise Science at the University of South Carolina, don't recommend doing this.
Instead, they recommend two different strategies to increase this move's effectiveness for glute growth while simultaneously protecting the lower back.
Lower the Thigh Pads to Mid-Thigh
In the back extension, the thigh pads are often placed higher up on the thighs, almost into the crease of the hip, says Arent.
"If I move the pad a little lower so it's hitting me at mid-hip, or on the meat of the thigh, you're changing the point of leverage a little bit," he says. "You're going to get a little more glute and hamstring involvement when you're pulling back up, because you've moved the fulcrum."
Shorten the Range of Motion
When bending all the way over on this bench to round the lower back, the lower back muscles are used to straighten the back, and the glutes are used to straighten the hips.
If you want to train your back and hips, that's good, Pignataro says. But if your focus is only on your glutes, you can stop the movement before your back begins to round.
So from the top of the move, you'd begin to fold forward at the hips, maintaining a flat back. When the angle of your hips reaches around 90 degrees, you'll stop, Pignataro says. Here, you'll squeeze your glutes to come back to the starting position.
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How to Do a Glute Extension/Hyperextension
If you're adding the glute extension to your workout, consider doing so later in your leg workout, Arent says. Other moves that you might be doing, including squats, lunges, deadlifts, and Romanian deadlifts, will need your hip-hinging muscles and back-stabilizing muscles to be strong, and the glute extension can tire these out.
Both experts suggest performing the move with lighter weights, focusing on form and the mind-muscle connection with your glutes and the muscles in your back. For your glutes, that means trying to actively feel the move in your butt as your hips are hinging.
Pignataro suggests performing this move for 2 to 3 sets of 10 to 20 reps per set. Once you can perform that with good form, add a five- or 10-pound dumbbell, working up to 10 to 20 percent of your body weight.
Safety Concerns With the Hyperextension
While it's good to train your lower back, when done incorrectly this move can cause unwanted pressure on the lumbar spine and, at worst, cause disc herniation. Here are a few tips our experts suggest to keep this move safe.
Don't Hyperextend at the Top
Despite the move sometimes being called a "hyperextension," one of the ways this exercise can end up resulting in pain or injury is by hyperextending your hips at the top of the move, Arent says. In this position, you've pushed your hips forward, your chest is puffed way out, and your head comes behind your butt.
"Here, your spine is in a less-than-ideal position," he says. Instead, work to keep your head, shoulders, waist, and knees stacked in a straight line. While there will be some natural arching to the back, don't push the hips forward to overextend in this move.
Use a Low Weight and More Reps
You may have seen videos online where trainees load this exercise with heavy barbells over their shoulders. But with your knees locked into the bench, this is a precarious position, Pignataro says.
"For the purpose of strengthening the low back, I think once you can do 20 repetitions with good form, you can grab maybe a five- or 10-pound dumbbell," he says. Hold the dumbbell in front of your chest by its ends, and do the back/glute extension this way.
Pignataro also thinks that when focused on the glutes, it's best to do this move with lighter weights.
"If you do high-repetition sets of this, it's really good for strengthening the mind-muscle connection with the glutes," he says, meaning you'll be better at firing those backside muscles when you need to straighten your hips, instead of compensating with the low back. "A lot of us struggle with this because we spend so much time sitting."
If you want to train your glutes to be as strong as possible in the shortened position-which the glute extension does-Pignataro suggests going heavier on other glute exercises that work this portion of the glute's range of motion.
"Hip thrusts, hip thrust machines, Romanian deadlifts-these will offer a safer way to load the glutes [in this shortened position] and still challenge the same thing," he says.
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Muscles Worked in Glute Extensions
When you're hinging your hips in this move, you're primarily using your glutes and the hamstrings, the muscles in the back of your thighs. When your back rounds at the bottom of the range of motion, the move focuses on the spinal erectors, or erector spinae.
The erector spinae aren't just your lower back, Arent says.
"It's that column of muscle that runs up from your lower back into your lower traps, [the muscles that shrug your shoulders]," he says. "It's like a set of cables that run up your back."
When those cables flex, they pull your spine straight. And that's the way they work at the bottom of the glute extension, straightening the back. The glutes and hamstrings straighten the hips, pulling the now-flat back up to the top of the move.
This exercise mostly works the glutes in the shortened position, Pignataro says.
Here's what that means: Muscles have a lengthened position, and a shortened position. When your arm is straight at your side and you start a biceps curl, the bottom half of the move is the lengthened position. At the top of the move, when your bicep is all bunched up, it's in the shortened position. Working just the top of the curl, then, would work the muscle in the shortened position.
For the glutes, that's primarily how the hyperextension works: It mostly trains the glute in the shortened position. Other moves, like the Bulgarian split squat, work more of the lengthened position.
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Glute-Ham Raise vs. Back Extension
The glute-ham raise is a similar exercise to the back extension/glute extension, but it's performed on a different type of bench. The glute-ham raise bench has two sets of round pads in the back for locking the feet in place, and a large, half-moon-shaped pad where the knees and lower thighs are usually placed.
When doing this move, the exerciser usually starts in a kneeling position with their body forming a straight line from head to knees. They keep this line straight and unbend their knees to go forward until their whole body is parallel to the floor while there's still a slight bend in the knee. From this position, they pull themselves back up to the start.
"You're pulling more with the hamstrings and the glutes" than on the back extension bench, Arent says. This move is kind of like a bodyweight version of the lying leg curl machine, he says.
The glute-ham raise (GHR) bench can also be used for a different kind of glute extension exercise, he says. To do it, turn around so that your face is near the feet-locking round pads. Many GHR benches have handles here. Grab them. The front of your hips will be on the half-moon pad, with your legs hanging off of it. Keeping your legs straight, squeeze your glutes to lift your legs from being bent 90 degrees until your body forms a straight line. This move kind of looks like the reverse of a leg lift on a Roman chair.