It's in a dark and wet corner of the gym. Half the gym-goers ignore it altogether. The other half use it to torture their spine as if it owes them money. The back extension machine can be a valuable tool for your training progression. It could also be the reason you're spending more time at the physical therapist than making gains. This article is going to set you on the path to a strong, resilient, and pain-free posterior chain.
When you look at a back extension machine, is your first thought to lay face down/ass up, or face up/ass down? If you're ass up, you're working ass, and if you're abs up, you're working abs.
Here's how to actually use that back extension machine
Using the back extension machine to work abs
Though the machine is intended for the back extension exercise (abs down), it is much more commonly used to train abs, and often unsafely and ineffectively.
Here's the proper way to train your abs on the machine.
The key is to not over-extend the back when doing your "sit-ups" on the back extension machine. This probably runs counter to every single person you've ever seen doing this exercise, including many of the athletes at the Crossfit Games. The below video is a great example of proper form.
Using the machine for your posterior chain
When used as intended, lying belly down, the back extension machine trains your hamstrings, glutes, and low back. Back extensions are a great supplemental exercise to the squat and the deadlift for developing your posterior chain. The key to all exercises on the back extension machine is to keep a straight (neutral) spine.
Your spinal erectors--those muscles on either side of your lower spine--are designed to work mainly isometrically in these movements. That's when a muscle contracts to maintain position, rather than to move a part of the body--think planks, not crunches.
In all of the movements that are possible on the back extension machine, the primary purpose is not to actually put the back into extension. If taken literally, the machine is poorly named.
It should be called the hip extension machine, because that's what you are primarily doing: extending your hips.
The back extension works your spinal erectors in the same way that the squat or deadlift does. You are using the spinal erectors to maintain your spinal integrity.
The way to target different levels of your posterior chain is conquered in the setup. Set yourself up for success by properly setting the machine to target the muscles you want. This is where the pad should hit your legs to properly train different muscle groups.
- Hamstring focused: low balance point (around mid-thigh)
- Glutes focused: middle balance point (just below hip-flexors)
- Low back focused: high balance point (hip-flexors on the pad) (not recommended)
Let's take a look at these three setups.
Hamstring-focused back extensions
In truth, the back extension is not the exercise you actually want to be doing to target your hamstrings specifically. To use the back extension machine for glutes, you want to be doing the glute ham raise. It's a leg curl using your entire body as the counterweight rather than a machine. It has the benefit of including your glutes and back in the movement as well, which is completely neglected when doing the same movement in a leg-curl machine.
Glutes-focused back extensions
To focus your back extension on the glutes, start by finding the sweet spot on the back extension machine where:
- Your hips aren't too high above the pad.
- Your hips aren't covered by the pad (too low). This forces rounding in the back and takes the glutes out of the equation.
- Your feet are splayed out at 45 degrees or further and separated as wide as possible (think the same stance as Parade Rest in drill).
Bret Contreras is the global authority on all things glutes. The guy literally has a Ph.D. in butts (see, kids, you really can be whatever you want to be when you grow up...even an assman.) Below, he takes you through the optimal setup and cadence for the glutes-focused back extension.
Back-focused back extensions
As previously mentioned, the back extension machine's name is a misnomer. You do not want to actually target your low back through repeated flexion and extension of the lumbar (low) spine.
Think of your back like a paper clip. When it is in a neutral position, it's strong and can easily hold together the first draft of your romance mystery novel. But if you bend it back and forth repeatedly, eventually the stress will cause the paperclip to snap, and your novel will scatter to the winds.
Likewise, repeated unnecessary extension and flexion of the spine can cause similar damage.
Before you claim fear mongering think of it like this…
Sure, we have muscles that can flex and extend the spine, but we also have complex joints like the hips, knees, and ankles that have the strongest and largest muscles of the body attached to them, that provide better range of motion and function than a bent spine ever could.
Why would you want to train a muscle group to do something it is designed to do as a fail safe (extend and flex the spine) when you could instead train the spine to isometrically hold strong while huge and powerful muscles like the glutes and hamstrings allow you to pull a truck, lift a pool table, or deadlift 400 lbs with ease.
Allow reason to prevail.