Ask anybody at your local gym what exercise they think is best for the backside. I can confidently say most people will say it’s the squat. From the beginning of time, the squat has been associated with developing and building strong gluteal muscles. The backside of the human body has become an essential part of many training programs. Athletes require a strong posterior chain for optimal performance in their sports. Society’s obsession, though mostly women, for a firmer, tighter and rounder butt is at its highest. In fact, many women I come across these days tell me they want bigger butts. The butt craze is in full effect!
So what is the best exercise for building the backside?
For years, the traditional squat was the go-to movement for butt and still remains a fantastic choice. But in recent years the hip thrust has gained popularity and emerged as a true rival for gluteal development. No research comparing the two exercises and its effect on the glutes had been conducted until Bret Contreras (www.gluteguy.com), the creator of the hip thrust, conducted one. Bret examines 3 key factors that impact muscle growth and development : mechanical tension, metabolic stress and muscle damage on the gluteal muscles. Majority of this is based on his findings.
Gluteal Biomechanics During Squat: Glute activation during a sub-max effort on a barbell squat isn’t what most people think it is. With the loaded bar on your shoulder, the glutes are relaxed and only begin to contract during the eccentric phase. Contraction during descent is very low and lowest at the bottom of the squat. In fact, research now shows that a ‘bucket squat’ or going too deep has little to no impact on the backside. The most amount of muscle contraction and activation takes place during the concentric phase; as you drive explosively upward from the bottom of the squat. Maximal contraction takes place during the middle of the rep, and slowly dissipates as you get back to the top.
Generally speaking, gluteal activation at the lowest phase of the squat is about 10-20% of maximal contraction, 20-30% at the start of the eccentric phase and 80-120% at the start and during the concentric phase. Overall the average gluteal activation percentage is about 60% of maximal contraction.
Gluteal Biomechanics During Hip Thrust: Using a sub-max load, the barbell hip thrust challenges the gluteal muscles a bit different from the squat. At the start of the movement, when the barbell is placed on the hip, the glutes are relaxed. The lifter thrusts the hips concentrically upwards until full hip extension is reached. Average gluteal activation during this phase is about 160% of maximal contraction. Keep in mind that full hip extension must be achieved (squeezing the buttocks as hard as possible at the top of the lift) for full benefits to be reaped. Unlike a barbell squat where the glutes are relaxed at the top, the gravity effect on the hip thrust (the barbell constantly trying to push you back down from the top) inevitably places constant tension on the gluteal fibers resulting in more of a burn.
There is little to no hamstring activation during the barbell hip thrusts. However, when the drive occurs at the balls of the feet as opposed to the heels, some may get some hamstring work. As a rule of thumb, the heels should always be favored.
Conclusion: Both the squat and hip thrust are excellent choices for building the backside. The fact that both movements keep the knees in a bent position means there is limited hamstring activation due to its shortening and therefore more involvement of the gluteal muscles. The hamstrings can only fire maximally when they’re continually lengthened. Although both exercises require hip extension which forces gluteal activation, the minimal activation during the eccentric phase and the lack of tension at the top of the squat doesn’t cause immediate burn and soreness unlike the hip thrust where there is constant tension. However because the fibers get a deeper stretch eccentrically during the squat more than the hip thrust, a lifter is highly likely to get sore in the days following a sub-max squat workout. The only small drawback is the lower back strength limits the load a lifter can use on the barbell squat and quadriceps and hamstrings activation takes away from maximal gluteal activation. The hip thrust, though easier to perform, is limited by glute strength, meaning once the glutes get tired from firing, a lifter will no longer be able to thrust thereby ending the set.
So which is the better choice for the backside?
Based on what the research shows, both exercises build and develop the gluteal muscles effectively and should be incorporated in a training program. Though the hip thrust offers more gluteal bang-for-your-buck results, it shouldn’t be necessarily favored over the squat nor should it replace it entirely. The barbell squat engages more of the lower gluteal fibers than upper fibers whereas the hip thrust fully activate both fibers. If you want a fully developed butt, you’ll have to routinely perform these two exercises. Performing only one and not the other will rob you of the full results. Both can be performed during a workout session or on separate days. The load must be challenging enough in order to illicit good gains. Generally speaking, a sub-max effort of about 75% of 1RM should suffice. Ideal rep range should be between 8 and 15.
Keep in mind that the front squat and goblet squat, which place emphasis on the front side of the body and anterior core, has very minimal impact on the backside and therefore can’t be relied upon for maximal gluteal development. While both exercises are low-back and knee friendlier than the back squat, they don’t fire the glutes nearly as hard due to the placement of the load. As a bonus, the deadlift along with other gluteal isolation exercises like the reverse lunge, stiff-legged deadlift and hip abduction movements will yield one heck of a backside.