How to Do The Jefferson Curl To Improve Low Back Pain

Flexibility/Mobility 9 min Read

Written by

Keith Hansen

To flex or not to flex? No, not your biceps—your spine.

We are taught to always lift with a flat back in strength training.

This recommendation comes with good reason. Lifting heavy things, loading the spine, and bending will likely hurt you. But at Seriously Strong Training, we think about strength training a lot and question everything.

So during all this questioning, we found that doing everything with a flat back may not be the best way to bulletproof your spine.

This is where the Jefferson curl comes in.

We found that the Jefferson curl could be an excellent exercise for spinal health—if you’re ready.

The Jefferson Curl

It’s like a straight-legged deadlift but pushed to the extreme.

I do not recommend this exercise if you have a back injury without consulting your physician first.

The Jefferson Curl is an exercise that moves your entire mobile spine from your lower back through your neck into flexion and then extension.

This move can seem scary at first, but it makes sense when we think about how any muscles grow and get stronger.

You need to put a muscle through a full range of motion to help it grow.

How to do the Jefferson Curl

To do the curl, stand on a box or bench at least 12″ high with your toes at the edge in a hip-width stance.

You can do this move with either a barbell or dumbbells, but a barbell is best once you work up to one. Start light.

From a tall standing position, slowly lower the bar or dumbbells toward your feet but keep them as close to your body as possible while keeping your knees slightly bent.

Your flexibility will determine how low you can go, but you want to reach as far down as possible. In the beginning, this may be near your toes, but as you gain flexibility, you will need to pass the bar in front and below your feet. That’s why you’re on the box–to allow for this deeper motion.

At the bottom, fully exhale, then inhale before returning slowly to the top, ensuring the bar stays close to your body. You may get some back cracking at the bottom with the breath. It feels like heaven. It’s even better than the chiropractor.

Do the exercise slowly & try to maximize your range of motion for the most benefit.

You may have to watch the video below and perform the move a few times to understand it. I recommend taking a video of yourself to compare it to ours.

Common Causes of Low Back Pain

Low back pain is common and usually persists for longer than we would like.

Most of the time, proper strength training can be the best remedy.

There are many causes of low back pain beyond the scope of this article. If you’re interested in learning more about low back pain, start with this article by Sam Spinelli about lifting with a flexed spine.

The two most common causes of pain I see from our clients are strength and posture.


A lack of strength can create protective back tightness and cause muscular lower back pain. The spinal column is a delicate structure, and there are a lot of different muscle groups surrounding it for support.

When muscles of the back and core lack strength, they increase in tension to create rigidity and provide “protection.” If you’re always tight, especially on one side, there may be a muscular imbalance in your back.

Poor Posture

A posture called anterior pelvic tilt can cause lower back pain. Anterior pelvic tilt is characterized by an arched lower back and a stuck-out butt.


Both weakness and posture can be remedied with the Jefferson curl and proper core training.

Let me explain how the Jefferson curl aids in bulletproofing your spine.

How We Gain Strength

There are two main contributors to strength gain. These are cross-sectional muscle area (the size/volume of muscle present) and neural improvements (your brain’s ability to recruit said muscle efficiently).

There are many other factors in strength, but they are beyond the scope of this article. However, if you would like to read more, Greg Nuckols has an excellent write-up on all of the factors in strength, and you can find that here.

So to get strong, we can induce hypertrophy and improve our nervous system.


The most recent science points to three main contributors to hypertrophy (muscle growth): mechanical stress, metabolic stress, and muscular damage.

Mechanical stress occurs when you load a muscle with tension. Heavier loads mean higher mechanical stress.

Metabolic stress occurs when you change the metabolic environment of a muscle. This happens typically through increased metabolic by-products created when a muscle is pushed to fatigue. This build-up of by-products is that burning sensation you get when you go to failure on an exercise.

Muscle damage occurs when you cause micro-tears in a muscle. This happens from all types of exercise, but eccentric-focused movement creates the most damage.

Additionally, to maximize hypertrophy, you must move a muscle group through a full range of motion. Unfortunately, many core exercises fail to put the low back muscles through an extensive range of motion, which means they do not grow as much as possible.

A proper strength training program incorporates all three of these stress mechanisms to maximize muscle growth and strength gain.

Because bigger muscles are stronger muscles.

Neural Improvements

When you strength train, your nervous system also plays a significant role in increasing strength. There are two neural improvements that improve strength: motor control and motor unit (muscle fiber) recruitment.

Motor control vastly improves when you first start strength training. Motor control is how well you can contract your muscles in conjunction to perform a specific movement. When you first begin to do a new exercise, you’ll look like a newborn deer trying to walk. Even without muscle growth, you would still get stronger by improving your motor control.

Motor unit recruitment improves strength later in your training career. As you continue to strength train for an extended period of time, the nervous system increases strength by increasing the number of muscle fibers that are contracting at one time. This is done by increasing motor unit recruitment. A motor unit is a part of the nervous system that innervates a set amount of muscle fibers. Increasing motor unit recruitment means that you can contract more muscle fibers during a given muscular contraction and therefore produce more force.

Strength Gain is Movement Specific

When you strength train—in any movement—the range of motion that you perform the exercise in is the range your muscles will get strongest due to neural improvements.

You will gain strength outside of this range of motion, but strength gains fall off significantly at ~15 degrees beyond where you began and where you ended the movement.

If you were to do an isometric curl where you hold the weight at a 90-degree bend in the elbow and train there for a while, you’ll get strongest at 90 degrees and gain some strength from 75 degrees of bend up to 105 degrees of bend.

If we apply this thinking to the spine, we can see that training the core and spine in just “neutral” is a great way to get strong in that “neutral” position.

But what happens if you pick something up outside of neutral? Or curl up to get out of bed in the morning? Or sit at your desk all day with a rounded back?

Often, injury happens when you’re in the most vulnerable position and not paying attention.

But sometimes, injury can even happen when you’re lifting past your limits.

To lessen the chances of this, you need to be strong in many different positions.

The Jefferson curl can help with this.

Progressing the Jefferson Curl

Once you’re ready to start performing the Jefferson curl, you need to know how to progress it carefully.

As I mentioned in the beginning, start with very low loads. Start with a dowel or PVC pipe the first time you do it to warm up.

Just feel how your body responds to this extensive range of motion, and then begin to add light weights slowly.

Remember, you are training your spine in its weakest position. Therefore, there is no need for heavy loads.

I recommend increasing your weight by no more than 5lbs at a time. This exercise is all about the quality of the movement.

This exercise is suggested to help avoid injury. So don’t let it cause harm because you progressed too fast.

Remember that back pain is multi-factorial. But being strong is an excellent way to cover your bases. Get stronger in every position and reap the benefits of the Jefferson curl.

Even if your pain improves and you’re getting stronger, be sure you have a solid core training program to maintain balance and strength.

The Serious Guide to Core/Abs Training

Keith Hansen

Keith was an All-State wrestler in high school and in 2007 hung up his singlet to attend Florida State University to pursue a B.S. in business management. He wasn't sure what industry he wanted to be involved in at the time, but soon realized after graduating in 2011 that fitness was the ever-constant activity in his life. Keith began studying to become a personal trainer and in 2013 earned the National Strength and Conditioning Association's Personal Trainer certification. After a short stint as a big box gym trainer he realized he wanted to bring something different to Tallahassee. Keith competes in Powerlifting, Olympic Weightlifting, and Crossfit.