The lying leg curl is an isolation exercise that is performed to target the knee flexors, specifically the hamstrings and calf muscles. It is performed by flexing the knee against an external resistance to improve strength and flexibility in the key muscles. Although performing lying leg curls is an effective way to develop and improve knee flexor strength, a number of factors including equipment availability may hinder an individual to perform the workout.
Alternative exercises that also target the knee flexors may be done in place of a lying leg curl. These alternative exercises may be performed with or without the use of machines or equipment, but provide the same benefits as doing leg curls, and include the following: Nordic Hamstring Curls, Slider Curls, Swiss Ball Hamstring Curls, and Hamstring Walkouts.
Understanding the mechanics of doing lying leg curls, the benefits it offers, and learning the muscles engaged in this activity is paramount in optimizing muscle growth and enhancing strength.
The lying leg curl is a lower body exercise that is very effective in isolating the knee flexors. It involves the use of a leg curl machine, and requires the participant to lie prone on the machine with the ankles tucked under a roller.
This exercise targets two main muscle groups, namely the hamstring muscles (biceps femoris, semitendinosus, and semimembranosus) and the calf muscles (gastrocnemius and soleus).
To perform a lying leg curl, the individual pulls their heels towards their buttocks while in the prone position. This pulls the weight that is connected to the machine. One repetition is completed by slowly lowering down the feet to the starting position.
The primary benefit of doing lying leg curls includes enhancing the flexibility and strength of the hamstring muscles. However, this also translates to a general improvement in an individual’s overall balance and stamina.
The lying leg curl ensures that the front and back of the legs are balanced both for aesthetic purposes and injury prevention. In addition, strengthening the hamstrings through the lying leg curl helps in performing activities of daily living.
The main disadvantage of performing lying leg curls is the need for a leg curl machine which is often only found in commercial gyms. The inaccessibility of the equipment required for the exercise makes it impractical.
Additionally, the movement involved in executing a lying leg curl is not considered a functional exercise, thus carry-over benefits to daily activities are not maximal.
Although lying leg curls are effective in developing the hamstrings, equipment unavailability is a factor why one can not perform the activity. The following alternatives may be performed to reap the same benefits as doing lying leg curls.
The hamstring walkout is an exercise that targets the hamstrings through knee flexion and hip extension. It is an equipment free exercise that anyone can do even in the comforts of their own home.
Although it only uses one’s own body weight for the activity, hamstring walkouts optimize hamstring muscular strength, endurance, and growth due to the increase in the muscle’s time under tension.
To perform hamstring walkouts, the participant positions themselves lying down supine on the floor. Both knees are flexed with the feet flat on the ground and placed near the buttocks.
The movement starts by pushing the hips upward and assuming a glute bridge. Upon getting into position, the knees are slowly extended by taking short alternating steps until the legs are completely extended and the weight is supported on the heels. This position is held briefly before taking short, alternating steps back in to return to the glute bridge position.
Another alternative to lying leg curls that require minimal equipment are slider curls. A slider curl is a hamstring workout that involves the use of sliding discs, or anything that would reduce friction between the foot and the floor such as a towel.
Slider curls are performed by placing the feet on a pair of sliding discs. The discs are slid along the floor towards the gluteal area to bend the knees, then the individual raises the hips to assume a glute bridge position.
From this position, the core is engaged while the knees are slowly straightened out until the knees are almost fully extended and the weight is supported on the heels. The buttocks must remain off the floor while the position is held for a second before sliding the heels back to return to the starting position.
Slider curls may be progressed when the activity becomes too easy for the individual. To make the activity more challenging, it may be performed with the other leg resting on the thigh, assuming a figure of four position. The same procedure is executed with only one leg carrying the weight.
The nordic hamstring curl is an exercise that focuses on eccentric strengthening of the hamstrings. It involves the use of one’s own bodyweight as resistance and as an eccentric contraction exercise, the hamstrings work to control the lengthening of the muscle against the resistance.
A nordic hamstring curl is performed by kneeling on a pad or mat with the ankle held in place by a partner, a fixture, or a weighted barbell. The person maintains the hip in extension while leaning forward from the knee.
Knee extension must be controlled by engaging the hamstrings to produce a gentle drop of the trunk towards the ground. When the person reaches the ground, they push themselves up using their hands to return to the starting position.
The swiss ball hamstring curl is an intermediate exercise that is effective in isolating the hamstring muscles that work to flex the knee and extend the hip. The activity relies on the person’s body weight for resistance and involves the use of a swiss ball. The movement is challenging because of the need to maintain the balance on the ball while performing the hamstring curl.
To perform a swiss ball hamstring curl, the individual lies down with their back flat on the ground and the heels propped up on a swiss ball. The arms lie on the side in line with the shoulders and should be flat on the floor to assist with stability. The hips are pushed upward by squeezing the glutes and pushing down on the ball with the heels.
Upon assuming the position, the ball is slowly pulled toward the body by bending the knees while continuing to push the hips upward all throughout the movement. A pause is observed when the ball is several inches away from the buttocks before slowly extending the knees to push the ball away and return to the starting position. The hips must remain elevated all throughout the activity. The movement is repeated until a set is completed.
Working the hamstrings is important for athletes such as deadlifters and runners, thus it is necessary to perform hamstring exercises and to avoid common mistakes when doing them. However, many individuals avoid “leg day” leading to decreased lower body strength.
In beginning hamstring training, one common mistake is not paying enough attention to the area through a lack of variety. In order to achieve optimal leg bulk, the hamstrings should be worked as much as the other muscles by adding variation to hamstring workout routines. The individual should not be content with just one exercise that targets the hamstrings.
Another common mistake in performing hamstring exercises is ignoring the eccentric part of the movement. This is often the part of the exercise that involves the release of the movement such as that in a lying leg curl where the eccentric part is the return to the starting position.
In hamstring exercises, the eccentric portion should be done slowly as this helps minimize injury occurrence as well as helps in recovery from injuries.
Lastly, there is a need to exercise and focus on each side individually which means working out the right and left hamstrings separately. This is done to further strengthen the muscles just like the arms are worked out individually.
The lying leg curl is a great exercise for isolating and strengthening the hamstrings. The available alternative exercises, however, are also able to provide the same benefits as well as add variety to workout routines which is of great advantage as variety further strengthens the muscles.
It is important to keep in mind to avoid common mistakes in performing hamstring exercises in order to optimize muscle building and strengthening.
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2. Taberner, Matt CSCS; O'keefe, Jason BSc; Cohen, Daniel D. PhD, CSCS. The Sliding Leg Curl. Strength and Conditioning Journal: June 2016 - Volume 38 - Issue 3 - p 117-121
3. Monajati A, Larumbe-Zabala E, Goss-Sampson M, Naclerio F. Analysis of the Hamstring Muscle Activation During two Injury Prevention Exercises. J Hum Kinet. 2017;60:29-37. Published 2017 Dec 28. doi:10.1515/hukin-2017-0105
4. McAllister, Matt J.; Hammond, Kelley G.; Schilling, Brian K.; Ferreria, Lucas C.; Reed, Jacob P.; Weiss, Lawrence W.. Muscle Activation During Various Hamstring Exercises. Journal of Strength and Conditioning Research: June 2014 - Volume 28 - Issue 6 - p 1573-1580