Table of Contents
The Jefferson Curl has a bit of a controversial reputation, and if you see someone doing it in the gym you’d probably assume they were performing the exercise all wrong.
That’s simply because of how the movement pattern looks.
Bending over and completely rounding the entire spine goes against pretty much everything we’re taught when it comes to strength training.
But, stick with us as in this article we’re going to be shedding more light on this unusual exercise, along with the Jefferson Curl benefits and potential risks when it’s not done properly.
What Is The Jefferson Curl
The Jefferson Curl is a challenging posterior chain exercise that involves folding forward into spinal flexion while holding light weights.
It’s very different from most exercises, like the squat and deadlift, where proper form is to maintain a neutral spine.
The reason we’re told to keep our back straight during most exercises is because it’s the safest option for limiting stress on your lumbar spine, therefore reducing the risk of injury.
This of course becomes even more important when we lift heavier weights.
Most lower back injuries occur when our spines are rounded or twisted while lifting heavy loads.
So you can see why some people would shy away from this exercise. But, when it’s done with correct form it can improve spinal health and mobility.
While there’s an element of risk when performing a Jefferson Curl, that’s not to say they should be completely avoided.
That’s unless you have a pre-existing back injury or suffer from lower back pain, in which case you’ll want to give this one a miss without seeking advice from a physical therapist or personal trainer.
What Muscles Are Worked Doing Jefferson Curls
The primary muscles worked when performing a Jefferson Curl include the erector spinae, hamstrings, and calf muscles.
You’ll also engage your core, particularly the obliques and rectus abdominis, which will help stabilize you during the descent and ascent as well as your quadratus lumborum, a deep-set lower back muscle.
As you’re going to be using muscles that articulate the spine, you’ll be strengthening many muscle groups that help to stabilize and support the spinal column.
As well as the erector spinae, this also includes the transversospinalis, interspinales and intertransversarii muscle groups.
Jefferson Curl Benefits
Despite our innate fear of rounding our lower backs, there are several benefits to the Jefferson curl exercise when it’s performed with the proper technique and to a full range of motion.
1. Reduces Lower Back Pain
As strange as it may sound, when you regularly perform the Jefferson curl you’ll strengthen the muscles that support your lower back therefore reducing common low back complaints.
This means it can be beneficial for those of you who spend a lot of your day sitting in front of a computer or are generally living a sedentary lifestyle.
This is because making these muscles stronger helps with better posture.
2. Improves Hamstring Flexibility
The Jefferson curl is an efficient hamstring stretching exercise and, as it’s a weight-loaded stretch, it’s one of the best ways of building range of motion to the back of the leg.
As your flexibility improves this leads to better strength and stability.
3. Spinal Decompression
Spinal decompression is when you reduce pressure within each lumbar disc.
As the Jefferson curl involves axial loading where the weight load shifts from your upper back to your lower back and then your hamstrings, this can help to create space between the vertebrae, potentially reducing pressure and promoting decompression.
4. Better Body Awareness
Performing a Jefferson curl requires a slow and controlled movement.
This encourages you to be more mindful at each phase of the exercise helping to promote better awareness of your body and how it moves.
As we mentioned, it’s common to have a fear of spinal flexion and while this is normal bending in this way is a natural human movement.
What’s more, it’s not just the Jefferson curl that involves curving your spine.
Many yoga-based exercises like the cat-cow and the forward-fold incorporate spinal flexion.
It’s worth mentioning that these aren’t weight-bearing so don’t carry the same level of risk.
5. Improved Core Strength
The controlled movement engages your core muscles to help stabilize your spine and control the descent and ascent helping with balance and coordination.
As you progress and add additional weight, this will promote more activation of your core thereby making these muscles even stronger.
Building core strength offers many benefits including better functional movement patterns, reduced back pain, and good posture.
Jefferson Curl Common Mistakes
When you’re new to this exercise it does pose a few risks, mainly when it’s not being done properly.
Remember, it’s a challenging movement that takes a lot of practice to get it right.
Let’s have a look at some of the common mistakes made when doing a Jefferson curl.
1. Thinking It’s A Hip Hinge Movement
The Jefferson curl is not a hip hinge exercise but rather a spinal articulation movement.
This means there is much more involvement of your vertebral column (the joints, vertebrae, and connective tissue) than your hips.
When doing the exercise, it’s important not to push back your hips as this is hip hinging.
Instead, you should concentrate on working your way down from the top of your neck and curling down.
2. Bending The Knees
Bending your legs when doing a Jefferson curl is common and will happen when you have tight hamstrings.
As you roll down, you’ll notice your hamstrings contract more, which is normal as it is a hamstring stretch after all.
However, people tend to bend their knees to allow for a greater range of motion which is overcompensating for poor hamstring flexibility.
You need to maintain straight legs with your knees locked out throughout to get the most stretch to your hamstrings.
Don’t worry if your range of motion doesn’t allow you to get very far.
Over time, and with regular practice, this will get better.
3. Using Too Much Weight
It’s important to start out with very light weight when doing a Jefferson curl.
Even though your hamstrings and calves may be able to take heavier weight loads, the muscles of your spinal column may not which could put them under significant stress.
Before jumping into Jefferson curls, it’s important to understand if this exercise will suit you.
It’s sometimes suggested that improving back strength by focusing on neutral or extension-based exercises is better when you’re just starting out.
It’s an advanced exercise that requires practice but if you are otherwise healthy with a good range of motion, then it’s certainly worth a try.
When looking to improve back strength and mobility a key thing to remember is that variety is needed for optimum results.
After all, our back is designed to move in many different ways.
So, as well as doing movements that involve spinal flexion you should also incorporate exercises that comprise back extensions, side bending, and rotations.
These can be bodyweight or weight-bearing depending on your ability.
Before you go, why not take a look at our suggested back extension exercises which you can do at home.