Nordic Curl: Benefits, Muscles Worked, and More

What sets the Nordic curl apart from other hamstring exercises is its absolute emphasis on eccentric contraction - meaning that the majority of the stimulus derived is from the hamstrings lengthening through a large range of movement.

In essence, the Nordic curl is a lower posterior chain exercise involving the lifter hinging forwards at the knees from an initial kneeling stance. This primarily works the hamstring muscles, and will require some sort of assistance to anchor the feet and calves to the ground.

What is a Nordic Curl?

Nordic curls are a traditionally bodyweight isolation exercise primarily targeting the hamstrings through eccentric contraction.

While mainly revolving around hip extension as the principle biomechanic, Nordic curls do not actually involve significant concentric movement and instead primarily derive training stimulus from resisting the pull of gravity as the upper body drops towards the floor.

In practice, Nordic curls are best used as an accessory movement after heavier movements like the deadlift, squat or lunge have already been completed. This is simply a result of its more isolated recruitment of the hamstrings, and for strategic fatigue accrual over the course of the workout.

Are Nordic Ham Curls the Right Exercise for You?

Although Nordic curls are perfectly safe and simple enough to learn for novices, they do have a learning curve and can result in injury when performed incorrectly.

For the best results, perform Nordic curls with an experienced training partner holding your legs and watching for poor lower back curvature as the exercise is performed.

Individuals with a history of hernias, hamstring injuries or those that have difficulty consciously contracting their hamstrings should avoid Nordic curls without prior approval from a professional.

How to do a Nordic Hamstring Curl

To perform a Nordic curl, the exerciser will begin by first kneeling on the ground, a partner, weight, bench or similar object holding their calves in place so that they do not tip over. A pad or pillow may be placed beneath the knees to reduce discomfort.

With the lower part of the legs secured, the exerciser forms a vertical line starting from the knees to the head - pushing their hips forwards and resting their hands at their sides so as to catch themselves at the top of the rep.

Now positioned correctly, the exerciser will slowly rotate their body forwards at the knees, keeping the hips extended and the torso straight. The hamstrings should be contracted so as to slow the upper body’s descent, which will become more difficult the more horizontal the body is.

Once reaching the limits of their hamstring mobility and strength, the exerciser can either splay their hands out and assist their hamstrings or entirely arrest their momentum through hamstring strength alone.

If following the former option, the exerciser will take their hands and stop their torso just shy of touching the ground, performing a mini push-up so as to raise their body back into a position where the hamstrings can pull them back to the starting stance.

If instead choosing to use the hamstrings, stop at the limits of their mobility and squeeze them so as to rapidly pull the torso back in the opposite direction.

Regardless of whether assisting the hamstrings or not, the repetition will feature a short concentric phase as the body is pulled back into an upright position after the first half of the movement has been completed.

Once back in the starting upright stance, the repetition is considered complete.

Remember that it is also possible to make the exercise easier by wrapping one half of a resistance band around the torso. This will reduce the load placed on the hamstrings and make the exercise possible for individuals without the strength to complete a full unassisted repetition.

What Muscles are Worked by Nordic Curls?

In actuality, Nordic curls only really work a single muscle group: that being the hamstring muscles at the back of the femur.

In particular, Nordic curls have been shown to call for comparatively greater activation of the semitendinosus and the short head of the biceps femoris - two of the largest portions of the hamstring muscles.

The hamstring muscles attach from the rear of the knee joint to the base of the pelvis, making them partially responsible for hip extension and flexion of the knee joint. 

As a component of the lower body, the hamstrings are essential for activities ranging from performing intense sets of deadlifts to leaping into the air or even for simply walking.

Of course, apart from the hamstrings, the core and spinal extensor muscles are also used to help stabilize the movement and adhere to correct form. Assisting these are the glutes, which help maintain hip extension throughout the movement.

What are the Benefits of Doing Nordic Curls?

Nordic curls have experienced a recent surge in popularity owing to the benefits they offer, both in an athletic and clinical context.

Excellent for Building Hamstring Strength, Mass and Stability

The main advantage to performing Nordic curls is its comprehensive development of the hamstring muscles. 

Not only does a lengthy eccentric contraction lead to muscular hypertrophy, but the high intensity and need to stabilize the entire body also improves hamstring power and isometric strength.

While the applicability of these developments is still up for debate, there is no denying that Nordic curls are among one of the better hamstring isolation exercises for overall muscular development.

Reinforces Knee Flexion, Hip Extension and Lower Joint Stability

The hamstrings are responsible for biomechanical movements like knee flexion and hip extension - as well as aiding with stability of both the knee and hip joint themselves.

As such, it is no surprise that regularly performing Nordic curls will also improve the lifter’s capacity to execute these movements. Those with poor hip extension range, stiff knees during flexion or general instability when squatting will see benefit from performing Nordic curls in a rehabilitative manner.

Reduces Future Risk of Injury

As a result of having stronger and more stable hamstrings, the Nordic curl also indirectly reduces the chance of future injury to the legs. 

Whether as a result of acute performance injuries, chronic overuse or any other physiological damage to the hamstrings, knees or hips - the benefits of doing Nordic curls both reduce the risk and mitigate the severity of lower body injury.

Of course, this doesn’t mean that Nordic curls will prevent injuries or can rehabilitate all forms of lower body injury. Speak to a physical therapist prior to employing Nordic curls for these purposes.

Easy to Modify and Progress as Needed

Nordic curls are not as strict in their ROM or set-up as other exercises, allowing for athletes of varying levels to still perform them with a few minor modifications.

One of the easiest ways to make the Nordic curl more accessible is to simply shorten the range of motion. This can easily be done by placing pads or a bench in front of the knees while performing the exercise, allowing individuals with weaker hamstrings to do the movement safely.

Likewise, the exercise can be made more difficult by increasing the range of motion instead, often with the use of a bench or similar set-up.

One of the Few Available Hamstring Isolation Movements

Often, exercises that work the hamstrings will also include the glutes or quadriceps as primary mover movers alongside the former. 

Although this is perfectly fine and indeed advantageous in a strength training scenario, it can make correcting weak points or targeting volume for hypertrophy quite difficult.

Fortunately, Nordic curls are one of the few available hamstring isolation exercises available without a significant equipment requirement or overly high level of complexity.

Keep in mind that the glutes are nonetheless still recruited by the exercise, only to a significantly lesser degree than the hamstrings.

For the best results, combine Nordic curls with movements like the glute ham raise, leg curls or donkey kickbacks to maximize lower posterior chain training volume.

Common Nordic Curl Mistakes You May be Making

While Nordic curls can have varying degrees of intensity and complexity depending on the handicap used, the following are generally applicable mistakes that you’re better off avoiding.

Rapid Eccentric Phase

The entire training stimulus derived from Nordic curls is primarily taken from the eccentric portion of the movement. 

Essentially, while falling towards the floor in a slow and controlled manner, the hamstrings are lengthening while contracted under tension - leading to small tears in the muscle and thereby inducing physiological adaptations.

As such, if you find yourself falling forward too fast or otherwise not allowing for a sufficient length of time in which the hamstrings are under tension, the exercise itself will be less effective.

Failing to Contract Hamstrings

Occasionally, lifters may find themselves performing Nordic curls incorrectly by contracting the wrong muscles. 

Depending on the equipment used, the calves, erector spinae, core or other muscles may be taking on the role that the hamstrings themselves are meant to fulfill.

Of course, this is entirely a mistake as the Nordic curl is meant to target the hamstrings. 

For those with difficulty consciously contracting their hamstrings as the movement is performed, try performing reverse Nordic curls as a method of reinforcing mind-muscle connection with the muscles therein.

Insufficient Range of Motion

While manipulating range of motion is one method of making Nordic curls more challenging or more accessible, a ROM that targets the hamstrings correctly is nonetheless needed. 

At a base level, aim for an angle that tilts the torso at an obtuse approximate angle of 60-70 degrees to the floor. This should properly engage the hamstrings without making the exercise too difficult for novices to perform correctly.

Remember that the further forwards the eccentric is held before dropping to the floor, the more the hamstrings are worked.

Bending at the Lower Back or Hips

In order to ensure that the hamstrings are truly isolated, it is important to extend the hips by squeezing the glutes and to maintain proper lower back neutrality.

Brace the core, ensure that the repetition begins with the spine evenly stacked atop itself and that the body forms a relatively straight line from head to knee.

Apart from targeting the wrong muscles, performing Nordic curls in this manner can also lead to injury as undue strain is placed on the lower back and spine. 

Failing to Progress (ROM, Load or Volume)

One common issue that many bodyweight exercises tend to suffer from is a general lack of planned progression. Exercisers may perform the Nordic curl the exact same way at the exact same intensity for extended periods, leading to a lack of progress and overuse injuries.

To avoid this, plan out a style of progression (i.e. larger range of motion, adding resistance or performing more volume) over the course of a set length of time. This will drive muscular development and keep the body steadily challenged over the course of multiple training sessions.

Alternative Hamstring Exercises to the Nordic Curl

If the Nordic curl is too difficult or demanding for your tastes, try the following alternative hamstring exercises out.

Glute Ham Raises

The Nordic curl is occasionally referred to as a “poor man’s glute ham raise”, as the two are quite similar in mechanics but the latter features a far greater level of intensity.

Glute ham raises involve the lifter placing themselves in a requisite machine as they bend from a kneeling stance to a fully horizontal one.

This targets not only the hamstrings, but also the calves and glutes to a larger range and greater level of tension than the Nordic curl.

Negative Deadlifts

The term “negative” simply refers to performing the eccentric phase of an exercise for a significantly longer period than the concentric. 

For deadlifts, this means performing the latter lowering portion of the exercise for several lengthy seconds prior to returning the bar to the floor. 

Much like Nordic curls, this provides excellent time under tension and eccentric training stimulus to the hamstring muscles - only in a far more intense, comprehensive and functional fashion.

Use negative deadlifts as a Nordic curl substitute in cases where you are already an experienced deadlift performer and find your lower posterior training volume to be lacking.

Double Elevated Hip Thrusts

The double elevated or two-bench hip thrust is an advanced variation of hip thrust where both the upper back and feet are elevated off the floor, requiring the lifter to begin with their hips in a relatively lower position than seen with conventional hip thrusts.

Double elevated hip thrusts are the ideal Nordic curl alternative for a similar time under tension and range without the complexity or stability demands of falling forwards from a kneeling position.

Frequently Asked Questions (FAQ)

What are Nordic Curls Good for?

Nordic curls are excellent for building size, strength and mobility in the hamstring muscles. 

In turn, these physiological improvements reduce the risk of future leg injury, improve overall physical ability and offer a host of non-athletic health benefits.

Why are Nordic Curls so Popular?

Nordic curls have benefited from a recent surge in popularity due to multiple scientific papers being published on their efficacy as both a rehabilitative and training tool. 

Among these studies is evidence claiming that Nordic curls reduce the risk of injury in professional soccer athletes and that the exercise recruits the hamstrings more than most other posterior chain exercises.

Do Nordic Curls Strengthen Your Knees?

Yes - but only in certain aspects. Nordic curls mobilize, stabilize and strengthen the hamstrings and their requisite tendons. 

Apart from those connected to the pelvis, the hamstrings also attach to the back of the knee joint, where they allow for knee flexion when the hamstrings are shortened during contraction.

References

1. Cuthbert M, Ripley N, McMahon JJ, Evans M, Haff GG, Comfort P. The Effect of Nordic Hamstring Exercise Intervention Volume on Eccentric Strength and Muscle Architecture Adaptations: A Systematic Review and Meta-analyses. Sports Med. 2020 Jan;50(1):83-99. doi: 10.1007/s40279-019-01178-7. Erratum in: Sports Med. 2019 Nov 7;: PMID: 31502142; PMCID: PMC6942028.

2. Sconce, Emma & Jones, Paul & Turner, Ellena & Comfort, Paul & Graham-Smith, Philip. (2014). The Validity of the Nordic Hamstring Lower as a Field-Based Assessment of Eccentric Hamstring Strength.. Journal of sport rehabilitation. 24. 10.1123/jsr.2013-0097.