Defending Spinal Flexion: It’s Not Always the Evil Step-Child We Make It Out to Be

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No offense to my future wife (t-minus 37 days until the big day), one of the greatest days of my life was the day I got my first Atari 26001 My game of choice: Defender.

The premise was/is simple: your planet is under invasion by waves of aliens and it’s your mission to “defend” it, as well as other astronauts.

Pew pew pew

Man, I spent hours playing that game.

I really have no other reason for leading with this story other than to say 1) it was an awesome game 2) the chick on the cover was hot and 3) the theme – defender – served as a nice segue to today’s topic……

Spinal Flexion


Like many other fitness professionals a few years back, I jumped onto the anti-flexion bandwagon.

I mean could you blame me?

Gulfs of research – in addition to anecdotal evidence – suggest that spinal flexion has its downfalls. To be more precise, however, I should state it’s repeated spinal flexion (and extension) taken into end range that’s the real culprit. Do that on a consistent basis, let it marinate with little to no strength training, and you have the perfect recipe to herniate a disc.

And as my boy, Eric Cressey, notes:

“If you want to see a population of folks with disc herniations, just look at people who sit in flexion all day; it’s a slam dunk.”

Of course, this doesn’t automatically equate to someone being in pain or complaining of back issues. There are plenty of people walking around with not one, but maybe even two, levels of herniations or disc bulges in their spine. And they’re fine.

In fact, in a landmark study published in 1994 in the New England Journal of Medicine, researchers sent MRI’s of 98 “healthy” backs to various doctors, and asked them to diagnose them.

– 80% of the MRI interpretations came back with disc herniations and bulges. in 38% of the patients, there was involvement of more than one disc.

And these were considered “healthy” backs, and those of people walking around with no symptoms what-so-ever.

Which goes to show: I’d trust an MRI about as much as I’d trust a barber with a mullet.

NOTE: this isn’t to insinuate that MRIs are a waste of time or aren’t valuable. That’s 100% false. But I’d be remiss not to state that we, sometimes, place far too much precedence in them.

Oftentimes leading to unnecessary surgery (which should be an absolute LAST resort).

Long story short: just because someone flexes their spine – and may or may not have a disc herniation – doesn’t mean their spine is going to explode.

And least we forget the Godfather of spinal mechanics and research Dr. Stuart McGill. The man has forgotten more about the spine than any of us could ever hope to remember. I’d be lying if I said his two books – Low Back Disorders and Ultimate Back Fitness and Performance – haven’t shaped most of my thinking and approach when working with clients and athletes with low back pain.

Who the hell am I to disagree with him?!?!

That would be like me starring Yoda in the face and saying something like, “Pffft, whatever dude. Force schmorce. What do you know??”

With that commentary in mind, as a fitness professional, most of the time (but not always), I’m not going to go out of my way to include more exercises or drills that place people into spinal flexion.

Particularly with the aforementioned “people who already sit a lot and live in flexion” scenario from above.

Taking it a step further (and to help appease those people who are probably hyperventilating into a brown paper bag reading this, assuming I’m saying spinal flexion is okay):

I typically avoid the following:

1. End-range lumbar flexion

2. Lumbar flexion exercises for those who are “stuck” in flexion.

3. LOADED spinal flexion

But Just to Play Devil’s Advocate For a Second

With point #3 – loaded flexion – there are some people out there who purposely train with a rounded spine and do very well.

Lets use the deadlift as a quick example.

We could make the argument – from a bio-mechanical standpoint – that a rounded back deadlift is efficacious because it’ll allow you lift more weight.

As Greg Nuckols explains in THIS amazing article:

“Rounding your back a bit shortens the length of the torso in the sagittal plane.  In non-nerd speak, it lets you keep your hips closer to the bar front-to-back so they don’t have to work as hard to lift the same amount of weight.”

Fancy chart making skills courtesy of Greg Nuckols

The picture on the right depicts a “neutral spine.” Taking natural kyphotic/lordotic curves into account, on the right, “neutral” equates to a spine that’s 15.3 inches “long” front to back.

On the left, with some significant rounding – albeit in the THORACIC spine (more on this point in a bit) – the the length of the spine is reduced to 11.7 inches. I.e., the hips are closer to the bar.

This in mind, if you watch elite level powerlifters you’ll notice that many of them do seem to “round” their back on max effort pulls.

But lets put things into context

A). It’s important to understand that for most, the rounding is happening in the t-spine and NOT the lumbar spine. The T-spine has more “wiggle room” in terms of end-range flexion compared to the lumbar spine.

B) They’re NOT rounding their lumbar spine.

C) Pulling 600+ lbs is heavy as f***. You try pulling that much without some rounding.

D) Guys (and girls) who are strong enough to be pulling 3-4x bodyweight have assuredly trained themselves to stay out of those last 2-3 degrees of end-range flexion. Moreover, they’ve also been in compromising positions enough that they’re able to stay out of the danger zone.

E) More importantly, you’re (probably) not an elite lifter, so I wouldn’t suggest you start training with a rounded back.

In the end, we could make the case for loaded spinal flexion. Just like we could make the case for Lisa and I being introduced as husband and wife for the first time with Juvenile’s Back That Ass Up playing in the background:


Neither are a good idea. Except for the second one.

When Is Spinal Flexion Okay?

Let me repeat, I generally avoid:

1. End-range lumbar flexion

2. Lumbar flexion exercises for those who are “stuck” in flexion.

3. Loaded spinal flexion

I BOLDED #2 because, well, I work with a lot of athletes and people who are the opposite. They live in extension and excessive anterior pelvic tilt, which can be just as deleterious for the spine as flexion.

I BOLDED “excessive” because I want to make it clear that anterior pelvic tilt is not a bad thing (it’s normal). And because some people are morons, will miss the bolded EXCESSIVE, and will still send me a note via email or social media saying how dumb I am for saying APT is bad for the spine.

People on this side of the fence face a whole host of other scenarios like Spondylolysis (referred to as an end plate fracture, most often on the pars interarticularis), Spondylolisthesis (forward disc slippage), femoral acetabular impingement, and what I like to call fake badonkadonk-itis.

In other words: some people don’t have a big butt, they’re just rockin some serious APT.

Cough, cough Jen Selter cough, cough

Kidding aside, extension-based back pain or extension-based issues are no laughing matter, and it’s in scenarios like these where spinal flexion is warranted (and encouraged).

This is where were start to dive into the PRI (Postural Restoration Institute) philosophy and discuss breathing and how it affects pretty much everything.

Many of the (breathing) drills we use at Cressey Sports Performance place people (people who are overly extended) into spinal flexion, which is a good thing.

Watch this video below and you’ll get a sense of what I’m referring to.

Lets take the regular ol’ boring prone plank/bridge.

Learning to perform this exercise correctly (getting to and maintaining neutral spine) is a game changer for anyone experiencing low-back pain regardless of whether it’s a flexion issue or extension.

However, I rarely ever see anyone perform this exercise right. Most people start in a okay position for about five seconds, but then quickly “fall into” an excessively extended posture where their head protracts towards the floor and/or their entire spine sags, essentially doing nothing but hanging onto their passive restraints and hip flexors.

The “core” isn’t doing anything.

It kind of looks like this.

Not coincidentally these are the same people who brag about being able to perform a plank for [insert pointless amount of time here].

When done correctly – I prefer an RKC style plank: feet together, palms flat, elbows being pulled towards toes (to increase tension), and fire everything (glutes, abs, quads, nostrils, everything) – the amount of time someone can perform it is drastically different.

20 seconds and you should be hating life.

You may also notice that I’m rounding my (upper) back above. This is on purpose and goes against conventional wisdom.

Here’s the deal.

I like to start people in a bit of flexion – especially those who are overly extended – because as fatigue kicks in they’ll end up in neutral (rather than past it).

And I’m done.

Did what you just read make your day? Ruin it? Either way, you should share it with your friends and/or comment below.

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Plus, get a copy of Tony’s Pick Things Up, a quick-tip guide to everything deadlift-related. See his butt? Yeah. It’s good. You should probably listen to him if you have any hope of getting a butt that good.

I don’t share email information. Ever. Because I’m not a jerk.
  1. Other days on the list: hitting my first Little League home run, earning a baseball scholarship to Mercyhurst University, getting my first article published on T-Nation, every Christmas Day for the past 38 years, and any time I see boobies.

Comments for This Entry

  • Rachel

    1. Congrats on your upcoming wedding! 2. So many laughs at all your references. I think yours is the funniest fitness blog out there. =) 3. Thank you for posting this! I teach pilates and we do a lot of work in flexion so it bothers me that everybody's jumped on the "never flex your spine or you'll die" bandwagon. There's a huge difference between passive flexion due to gravity (as in being slouched at a desk) and active flexion where your body has to work to overcome the force of gravity (as in pilates movements...which tend to be quite similar to all the functional training stuff like hollow body holds). I think there's a need to teach people how to control flexion, and with control, you won't die...or herniate a disc. :o) 4. Your plank comments made me think of something I heard another coach once say..."in planks, we should be like Steve Urkel, not like supermodels" (ie slightly rounded position as opposed to arched low back/butt sticking out). I thought that was great, wish I could take credit. Maybe you had to be there to see his impressions too though haha.

    April 23, 2015 at 3:07 pm | Reply to this comment

    • TonyGentilcore

      Thanks Rachel. It all comes down to that pesky pendulum. Take any topic in the fitness industry and you'll inevitably find people who take it too far to the right or left. I like to think that there's ALWAYS a middle ground somewhere, at some point.

      April 27, 2015 at 9:59 am | Reply to this comment

  • doc

    Im going to read the MRI study you referenced. Not sure if it implies that MRIs are unreliable (rather the radiologists interpreting the image), or that the healthy volunteers were just asymptomatic (with their legitimate herniated discs). Very interesting.

    April 24, 2015 at 9:37 pm | Reply to this comment

    • TonyGentilcore

      Cool. I don't think it said that MRIs are unreliable either. I just feel it's important to note to people that just because an MRI says you have a disc herniation (or whatever), that it's not a death sentence. And, surgery isn't ALWAYS going to be the answer....;o)

      April 27, 2015 at 10:01 am | Reply to this comment

  • Adam Trainor

    Thanks for sharing the news about your wedding. Congratulations. I can't think of an exercise I do without firing my nostrils. I think it's a good example of never say never, but understand how to intelligently educate people on the risks involved with extreme examples. Teach people how to sort through why someone they respect in fitness might say, "You should never ever never ever______." This robust understanding of movement seems to be the new black. Or is it Orange? Meh.

    April 25, 2015 at 9:51 am | Reply to this comment

    • TonyGentilcore

      Red flag starts flashing for me whenever the words, "always, never, and everyone" start entering the conversation. Again, just to reiterate, I still do feel flexion can be problematic for a lot of people. This post was just to showcase a clear example of when it's "okay," and that we can't be so alarmist when it comes to the anti-flexion commentary.

      April 27, 2015 at 10:03 am | Reply to this comment

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  • Shane Mclean

    So many golden nuggets in this article mate, I don't know where to start.......the gay owl, really? Congrats on making the articles of the week once again mate.

    April 26, 2015 at 9:51 am | Reply to this comment

  • Stephen Clipp

    Do you have a ratio of 'what is a safe flexion loading amount,' compared to, say, your deadlift? I've done low back raises, loaded and unloaded, for decades with no ill effects (and I'm far from a physical outlier.) For that same timeline, I've done deadlifts, but only with a lumbar lordosis. A few months ago, I stumbled across the 'Urkrainian deadlift,' videos posted by Louie Simmons and others, thought I'd give it a run with a light weight. Lots of muscular soreness, no perceptible injury or downsides. I can now do this with half my max deadlift weight, don't want to push it farther. Dan John has written about doing heavy loaded low back raises is his Nottmeyer (sp?) years, also presumably without injury. Christian Thibadeau has promoted a combo low back raise/horizontal row, where one extends against (what can be) significant resistance. So. Can't lift the same amount with a totally rounded back, at least not safely. Trying to extend from flexion with too much resistance will herniate a disk. But - We can all flex, then extend our backs to some degree. Do you have a metric of resistance with flexion, to resistance with neutral/some extension?

    April 28, 2015 at 10:24 am | Reply to this comment

  • Carlos Weil

    Amazing references in this article, I enjoy it very much, smart and funny. Congratulations

    April 29, 2015 at 8:33 pm | Reply to this comment

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  • Kate Gibbs Halie Moma

    Awesome article! Easily understandable, well grounded scientifically, funny as hell. I definitely appreciated this read. I am a yoga instructor and I'm curious what your thoughts are on yoga poses that require deep flexion (like head to knee forward folds) or deep extension (like big back bends, ie. King pigeon pose ). I've read that poses like these that move into joint end range, or beyond, are only possible though hypermobility of the ligaments.

    August 17, 2015 at 10:43 am | Reply to this comment

    • TonyGentilcore

      Thanks Kate. Once people start entering "end range" things can get dicey, and that's generally when people start getting hurt. The same rules that personal trainers and strength coaches use should apply to yoga instructors too. There SHOULD be some semblance of individualization involved. Not everyone is meant to do those poses you suggest; and they should be regressed (or progressed) accordingly depending on one's goals, injury history, and current ability level.

      August 17, 2015 at 12:43 pm | Reply to this comment

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  • Shane Mclean

    Congrats Tony on making the article OF THE YEAR( yes, this deserves bold caps) on the PTDC. Your blog site is one of the best fitness sites out there.

    December 27, 2015 at 9:36 am | Reply to this comment

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