Science is Self-Correcting – The Case of the Hip Thrust and its Effects on Speed

The hip thrust has gained a lot of momentum in the past decade, and people employ the hip thrust in their training for a variety of reasons. I recently polled my newsletter list and social media followers and received over 7,600 responses as follows:

Reasons why people thrust

As you can see, around 63% of people hip thrust primarily to attain a better butt, 8% to improve running and jumping performance, 12% to boost squat and deadlift strength, and 16% to prevent injuries. This article is geared toward sports scientists, strength coaches, and the 8% of people who hip thrust for functional performance.

Hip Thrust Wiki Page

I’m going to reference various studies in this article. In case you’d like to find a certain paper, know that I keep THIS Hip Thrust Wiki page up to date. It includes all the latest studies, anecdotes, experiments, and theories pertaining to hip thrusts.

Science Prevails Over Time

Science is the systematic knowledge of the physical and natural world gained through observation and experimentation. In theory, it should be perfect. Because humans are inherently flawed, however, we inevitably muck up the flow of science. Nevertheless, given ample time, science is self-correcting and converges on the truth.

In this article, I am going to use the case of the hip thrust as a teaching tool relating to human biases and how they effect scientific progression.

How Did the Hip Thrust Hysteria All Begin?

Almost 11 years ago, I thought up the barbell hip thrust in my garage gym in Scottsdale, Arizona. Since then, I’ve been on a mission to popularize the movement. Click HERE to read about the evolution of the hip thrust.

When I began programming the hip thrust to my clients, they reported improvements in a variety of physical and functional outcomes, most notably: increased glute size, increased running speed, and improvements in low back pain. I have sought to provide evidence for these observations over the years. In fact, I even proposed the force-vector hypothesis, which states that the direction of the force relative to the human body plays a large role in determining the functional adaptations of that exercise. Click HERE to read the classic article on Force Vector Training.

I eventually got around to examining this exact topic for my PhD thesis. First, my team found that the EMG activity in the hip extensors (glutes and hammies – the “sprint muscles”) was markedly higher with hip thrusts compared to back squats. Click HERE to read the article on squat vs. hip thrust EMG activity.

Then, my team examined the force-time characteristics between squats and hip thrusts and found that the squat was superior in eccentric and total (but not concentric) measurements. Bear in mind that sprint acceleration is mostly concentric in nature. Click HERE to read the article on squat vs. hip thrust forcetime data.

Next, two strength coaches in New Zealand carried out the training study, and it was found that hip thrusts led to better acceleration improvements (and horizontal jump and isometric mid-thigh pull improvements, but not vertical jump improvements) than front squats in adolescent male athletes. Click HERE to read about the first RCT on hip thrusts vs. front squats on performance.

My team then found in a twin case study that hip thrusts led to better outcomes in glute hypertrophy and horizontal pushing force than back squats. Click HERE to read the classic twin case study on squats vs. hip thrusts.

Shortly thereafter, I was contacted by an American strength coach who had stumbled upon similar patterns of findings in a pilot study he’d run for his master’s thesis. Click HERE to read Michael’s master’s thesis on squats vs. hip thrusts vs. deadlifts.

Consider all of this information, I was on cloud nine! My theories were essentially validated –  at least in my mind. With this much evidence pointing in the same direction, how could my predictions possibly be wrong?

Jumping the Gun

I took this information and ran with it, posting numerous article links and infographics on my social media channels relaying the news that hip thrusts are very well-suited for improving speed and that the force vector hypothesis was legitimate.

Hip Thrust Infographics

Unfortunately, I spoke too soon. The combination of 1) my inherent biases as an inventor, 2) my role as an online educator always seeking to provide cutting edge information to my followers, and 3) my greenness as a scientist prevented me from exhibiting a more tempered approach to the emerging evidence. Sure, I was very cautious in my conclusions and made sure to point out limitations in the peer-reviewed published articles. On social media, however, I was overenthusiastic and hasty; I shared, liked, favorited, re-tweeted, and reposted everything that confirmed my bias.

If I was a professor speaking to a classroom full of students about the hip thrust, I would have cautioned them by pointing out that 1) we have EMG, force plate, and ultrasound data but only one training study involving adolescent males, 2) we have a case study involving twin females that appear to be better-suited anatomically for hip thrusting than squatting, 3) we have a confident, charismatic, and undoubtedly biased inventor singing its praises, and 4) we need much more research examining the nature of transfer from hip thrusts to performance. As a prolific S&C educator with a large online following who gets rewarded for being “ahead of the research,” making bold predictions, and playing to the masses – in addition to being a biased inventor, might I add – I failed to be as scientific.

Fast forward two years: two studies have just been published, one of which I was a peer reviewer for and for which I recommended acceptance. Both of these studies had subjects solely perform the hip thrust while noting the changes in sprint speed – or better yet, the lack of change in sprint speed.

Click HERE to access study #1:

“Effects of Hip Thrust Training on the Strength and Power

Performance in Collegiate Baseball Players”

Click HERE to access study #2:

“Heavy Barbell Hip Thrusts Do Not Effect Sprint Performance:

An 8-Week Randomized-Controlled Study”

In the first study, 20 college male baseball players hip thrusted 3 times per week for 8 weeks in a progressive, periodized fashion and took their 3RM hip thrust strength from 295 lbs to 392 lbs (36% gain) and their 1RM parallel back squat strength from 185 lbs to 237 lbs (31% gain), with no improvements in vertical jump, broad jump, or 30m sprint speed.

In the second study, 21 university athletes (15 males and 6 females) hip thrusted 2 times per week for 8 weeks in a progressive manner using a 5 x 5 loading scheme and took their 1RM hip thrust strength from 356 lbs to 453 lbs (27% gain), with no improvements in 40m sprint speed.

Both utilized reasonable protocols that closely aligned with programs we commonly see in the field. Importantly, both studies showed very large increases in hip thrust strength.

Upon reviewing both of these papers, my initial reaction was to read the articles with skeptical eyes. I was highly convinced that hip thrusts are a great speed builder, after all.

It makes so much sense: to move forward faster, you have to produce high amounts of horizontal force, and this is largely carried out by the hip extensors. What better exercise is there than the hip thrust to accomplish this? Moreover, I’ve received, on average, an email a day for the past seven years from someone informing me that the hip thrust has enabled them to run faster than ever before.

With all of this in place, how and why did the subjects not gain speed, and how could I have been so wrong?

The great thing about science is that it is self-correcting over time. Critical findings are often never duplicated, and we’re frequently led on wild goose chases in the literature. But make no mistake about it: science eventually converges on the truth.

Anecdotes Aren’t All That

When I was training athletes 10 years ago and making these observations, we were not just performing the hip thrust. I had a fully equipped training studio, and in addition to plyometrics and sled pushes, we performed back squats, box squats, front squats, walking lunges, Bulgarian split squats, high step-ups, deadlifts, Romanian deadlifts, stiff-legged deadlifts, single-leg Romanian deadlifts, good mornings, kettlebell swings, horizontal back extensions, 45-degree hypers, reverse hypers, glute ham raises, and Nordic ham curls. Since we often performed hip thrust variations first in the workout, and I had a special machine designed for these (the Skorcher), the athletes that I trained typically attributed any speed improvements to the hip thrust. When I asked why they thought that way, they’d respond, “I can feel my glutes working on the ground similar to how they work during the hip thrust.” In actuality, it could have been any combination of the aforementioned exercises.

These statements were ultimately what led to the formation of the force-vector hypothesis, but they were subjective forms of evidence based on perceptions, and perceptions aren’t always valid. This line of reasoning is a logical fallacy known as post hoc ergo propter hoc, which is Latin for, “after this, therefore because of this.” It states that, “since event Y followed event X, event Y must have been caused by event X.”

Two more important points are worth mentioning. First, many of the clients reporting speed increases were runners and not sprinters. I felt that since the hamstrings and glutes become increasingly more important with increased running speed, then hip thrusts can only be more effective for faster running speed. Second, we never performed barbell hip thrusts off a bench. I never even thought of barbell hip thrusts until I wrote my glute e-book and was trying to figure out a way to teach hip thrusts to the masses, knowing full well that only a very small percentage of people would ever have access to a Skorcher (which I never ended up selling).

Skorcher Hip Thrust Variations circa 2007

There are, in fact, key differences between a barbell hip thrust performed off of a bench versus a Skorcher. In the case of the barbell hip thrust off a bench, the hips don’t sink as deep, the knee angle never opens up, and quadriceps activity is very high. The Skorcher barbell hip thrust causes the hips to dip down deep, which increases hip flexion and opens up the knee angle (knee extension) and stretches the hamstrings. This is essentially a stretch-shortening cycle for the hamstrings, and the hamstrings are likely the most important sprinting muscle.

My clients did barbell hip thrusts, band hip thrusts, barbell plus band hip thrusts, barbell plus chain hip thrusts, and single-leg hip thrusts off the Skorcher. They also performed their repetitions explosively and used lighter loads for higher reps compared to what I ended up employing in later years.

It’s still possible, then, that hip thrusts are great speed builders. However, the style of hip thrust should be similar to what was performed on the Skorcher. But again, the evidence that formed this hypothesis was based on logic (force vectors) and anecdotes from runners who were performing a wide variety of lower body exercises.

The Pendulum Swing

In fitness, pendulums are always swinging. The hip thrust saw a rapid rise in popularity over the past decade, and the two recent papers will likely cause the pendulum to swing the other way, especially with strength coaches. However, the two published papers had limitations, just like all papers do, in that they only utilized heavy loading protocols and only examined explosive functional parameters.

In time, the pendulum will likely continue to swing back and forth when papers are published supporting and not supporting the transfer of hip thrusts to various neuromuscular performance measures.

Current Opinions of a Biased Scientist

Now that I have pointed out my clear biases, what are my current thoughts on the hip thrust? When and how should they be used?

The vast majority of personal training clients train primarily for physique improvements. I firmly believe that hip thrusts are the best glute building exercise, more so than squats, deadlifts, or lunges. But right now, the only evidence I have is a ton of anecdotes (recall from earlier why anecdotes are a weak form of evidence) and a yet-to-be-published case study involving identical twins (many of you will remember the twin experiment where the hip thrust twin grew her glutes by 28% in terms of muscle thickness, and the squat twin by 21%).

Yes, we need better research. Some of this is underway; colleagues in Scotland are working toward obtaining this information. For those seeking greater glute development, the thrust is still a must, in my opinion.

But what about athletes? Are they worthless since they fail to improve sprint speed?

Here’s my take: right now, we have a paper involving adolescent male athletes showing superior improvements in acceleration, horizontal jump, and isometric mid-thigh pull strength, but not vertical jump with the hip thrust compared to the front squat; we have a pilot study on athletes showing promising potential; we have a controlled case study on twins showing superior glute gains and maximum horizontal force production compared to back squats; we have a study on college athletes showing no speed improvements despite large increases in hip thrust strength; and we have a study on baseball players showing large gains in hip thrust strength and surprisingly high transfer to the squat despite no improvements in speed or vertical and horizontal jump.

It may be that hip thrusts are more beneficial for younger athletes than more developed athletes. It may be that heavy hip thrusts are only good for developing maximal pushing force. It could be that dynamic effort hip thrusts and/or Skorcher-style hip thrusts, but not barbell hip thrusts off a bench, transfer well to sprinting.

We still need much research on the hip thrust examining other possible benefits to athletic performance, including agility/change of direction, throwing velocity, punching power, swinging power, and pushing force. However, the benefits of heavy barbell hip thrusts performed off of a bench on sprinting speed appear to not be as impressive as once thought. They may not improve sprint speed at all, in fact.

While we have several plyometric studies that support the force-vector hypothesis for resistance training, the hypothesis isn’t complete. You can’t just pick any old horizontal exercise and expect it to improve sprint acceleration or speed, nor can you perform any old vertical exercise and expect it to improve vertical jump. The exercise has to pass the real-world test, and the tempo, load, range of motion, and variation must be closely considered.

Despite what you commonly hear from powerlifters, the hip thrust is undeniably a great assistance lift for the squat – at least in the short-term. From the adolescent male athlete study, to the twin case study where I witnessed the hip thrust twin perform a not-so-pretty 95lb back squat in week one and a beautiful 135lb back squat in week six despite never performing a single repetition of a squat in between (not even in the warmup), to the pilot study, to the baseball player study, we are consistently seeing marked squat improvements from hip thrusting.

Interestingly, a recent meta-analysis showed that squats improve sprint speed. If A leads to B, and B leads to C, logical reasoning tells us that A should lead to C. In other words, if hip thrusts build the squat, and squats build sprinting speed, hip thrusts should also build sprinting speed, especially considering the fact that hip thrusts activate the hamstrings to a much greater degree than squats, and the hamstrings are the primary speed muscle.

As I’ve mentioned, this may have to do with the manner of execution of the hip thrust. Shoulder-elevated hip thrusts may be far inferior to shoulder- and feet-elevated hip thrusts (in which the hips sink low and the hamstrings are stretched) for improving speed, especially if coupled with explosive contractions.

As you can see, many thoughts are presently running through my mind. Based on the information I have presented thus far, I recommend that strength coaches and athletes continue to hip thrust, but when seeking speed improvements, opt for dynamic effort and Skorcher-style hip thrusts.

Where are we now?

• We need another study on adolescent males conducted by an independent lab to confirm the findings from my PhD thesis.
• We need a study examining glute hypertrophy between hip thrusts and other popular glute exercises such as squats and deadlifts. If it is found that hip thrusts effectively build the glutes, then we need to figure out why this increased glute mass is not translating to faster spring times. Could it be that some exercises build more functional glute mass than others? If so, this would refute what I’ve been saying over the past decade.
• We need comparative studies employing the same protocol between the hip thrust and the alternative exercise. When studies only measure the effect of a protocol involving one exercise, we’re unable to ascertain whether it’s the exercise or the loading protocol to blame for failing to improve performance.
• We need studies examining the effects of hip thrusts on maximal horizontal pushing force and sled pushing proficiency, as these are important qualities in sports such as football, rugby, and martial arts.
• We need studies examining the effects of hip thrusts on agility/change of direction, throwing velocity, punching power, and swinging power.
• We need a study examining free sprinting versus hip thrust plus free sprinting. It could be that hip thrusts are additive in nature when combined with sprinting, or the opposite (they could negate or neutralize the positive effects of sprinting).
• We need studies examining the effects of hip thrusts on pain, rehab, and injury prevention for the anterior hips, knees, lumbar spine, and hamstrings.

Sprinting speed is a very difficult ability to improve upon. Hell, check out THIS experiment which found that a program consisting of heavy parallel and quarter squats, mid-thigh pulls, and SLDLs failed to improve vertical and horizontal jump and 10 and 30m sprint performance. We perform many movements in strength and conditioning that, when performed alone in isolation, would fail to lead to meaningful improvements in speed. For example, chin-ups, rows, bench press, military press, dynamic and static core exercises, and certain lower body movements probably wouldn’t improve speed per se, but they would improve other elements of athletic performance and help bulletproof the body against injury.

As I’ve alluded to, I believe that hip thrust mechanics and loading protocols can be manipulated to transfer quite favorably to sprinting speed, but this is yet to be determined. It is quite possible that hip thrusts may rapidly improve a weak link in, let’s say, 3 out of 10 people, thereby enabling them to run faster and perform better, but when averaged out, no effect is seen. On the contrary, based on the same premise, hip thrusts may not be beneficial to some individuals and could actually make them slower due to fatigue-related adaptations.

It may be that I’m guilty of committing the No true Scotsman fallacy whereby I re-characterize the situation solely in order to escape refutation of the generalization:

Me: Hip thrusts improve sprint speed

Recent research: Hip thrusts don’t improve sprint speed

Me: Well, real hip thrusts (explosive Skorcher style) improve sprint speed

In the meantime, use the available evidence to form your own conclusion, and take into consideration anecdotes, logical rationale, and randomized controlled trials, the last of which should be given more weight because they’re controlled. If the hip thrust has worked well for you, recall that there are large individual differences in response to training.

Humans are biased. Let me state this more firmly: every human being on the entire planet is inherently and extremely biased. Our brains can’t help it. As the inventor of the hip thrust, even if I try to be the best scientist I can be, I’m going to view hip thrusts in a favorable light when possible. My loyalty, however, is to science, not to hip thrusts, any financial interests in the Hip Thruster, or any future invention I may develop. When evidence emerges, a good scientist flows with the research; he does not dig his heels in and stubbornly cling to his long-held beliefs. Based on the latest research, barbell hip thrusts performed off of a bench as a sole lower body exercise do not appear to benefit sprinting speed in adults. Future research will determine if explosive hip thrusts with greater range of motion are beneficial for sprint speed.

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