Clamshells

Clamshells are a simple yet effective movement that targets the gluteus medius and gluteus minimus muscles.

Often overlooked and under-trained, these muscles play a role in hip mobility and posture and can even affect athletic performance.

Clamshells are a beloved exercise by physical therapists. They help users improve mobility, reduce tension, and prevent lower back and knee pain — all in a single exercise.

You might be an athlete looking for an edge, or maybe you’re recovering from an injury. Either way, incorporating clamshells into your routine can help you address weaknesses in your physique to feel stronger than ever.

In this article, we’ll explore different clamshell benefits and tell you everything you need to know to get started.

How To Do

  1. Lie on your side with your legs stacked and knees bent at an approximately 90-degree angle. Rest your head on your lower arm to support your neck.
  2. Engage your core to stabilize your body and prevent your hips from rotating as you move your top leg.
  3. Keep your feet firmly pressed together, and exhale as you lift your top knee as high as you comfortably can. Your hips should remain stacked throughout the movement.
  4. Hold the top position for a second, feeling the glutes engage.
  5. As you inhale, slowly lower your knee to the starting position.
  6. Repeat as necessary before switching sides.

Tips From Expert

  • As you lift your knee, ensure that your hip doesn’t roll backward. It should remain stacked on top of your other hip throughout the exercise.
  • Placing your hand on the top hip can help ensure it doesn’t move as you move the top leg.
  • Perform the movement slowly to help enhance mind-muscle activation. This will ensure that you isolate the iliopsoas and gluteus muscles and that they reach maximal activation.
  • Adjusting the angle of your hips relative to your torso will target different muscles. Experiment to find the setup that works best for you.

Optimal Sets and Reps

Exercises are not one-size-fits-all. Instead, they should be tailored to best meet your unique fitness goals. One way to make your workouts work for you is to use evidence-based recommendations for sets and reps.

Training Type Sets Reps
Strength Training 3–5 10–12
Hypertrophy N/A N/A
Endurance Training 2–3 20+
Power Training N/A N/A
Optimal Sets & Reps of Clamshells

How to Put in Your Workout Split

Clamshells are an excellent exercise for glute activation and can help to improve hip flexor strength.

Due to their loading limitations, they are not an ideal option for hypertrophy or power training. That being said, difficulty levels can be increased by using weight bands or placing a weight on the top leg.

However, most people use this exercise to rehabilitate lower body injuries or with other warm-up or cool-down exercises. We’ll discuss these options in greater detail below.

  • Warm-up: Clamshells are often used as a hip activation exercise before lower body workouts. This helps to engage the glutes and stabilize the hips, especially before squats, lunges, or deadlifts.

  • Injury rehabilitation: Physical therapists often recommend clamshells as a low-impact exercise for strengthening the hips to alleviate knee or lower back pain.

  • Active recovery: Massage is generally considered the best active recovery method for reducing muscle soreness. However, performing clamshells on recovery days without heavy resistance can also aid muscle maintenance and mobility.

  • Glute-focused workout: Clamshells are a great addition to glute circuits, especially those performed at home. Pair them with exercises like hip thrusts, glute bridges, and fire hydrants to fully target the glutes.

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Primary Muscle Groups

Gluteus

Large, superficial muscles located at your buttocks just below your lower back area.

Gluteus

The gluteus muscle group, located on the buttocks, is made up of three smaller muscles. These include the gluteus maximus, gluteus medius, and gluteus minimus.

Generally, movements that involve the glutes heavily target the gluteus maximus — the largest of the three muscles. The gluteus maximus powers hip-hinging movements like squats and even deadlifts.

However, clamshells are unique because they more heavily target the glutes medius, and minimus muscles. These muscles are responsible for externally rotating the hip and hip abduction (moving the leg away from the body).

The gluteus medius, for example, has an activation rate of approximately 33% during the standard clamshell exercise. Activation rate refers to how much the muscle fibers are engaged during a certain movement.

This rate is almost 10% higher than during other clamshell variations, which are listed further in the article. This makes standard clamshells one of the most effective gluteus medius exercises for strengthening this often under-trained glute muscle.

Secondary Muscle Groups

Obliques

Muscles located on the sides of your rectus abdominals. Runs on the sides of your trunk.

Iliopsoas

Muscles starting at your back, moving through your pelvis connecting just below your groin.

Iliopsoas

The iliopsoas consists of two muscles, the psoas major and the iliacus. These muscles merge to connect the lower back vertebrae (spine) to the femur (upper thigh bone).

During clamshells, it plays more of a stabilizing role rather than contributing power to the movement. It contributes to pelvic and spinal alignment, allowing the gluteus medius and minimus to perform the movements effectively.

That being said, the entire anterior hip flexor muscle group, including the iliopsoas, is highly activated during clamshells. The group, which includes more than nine different muscles, has an activation rate of almost 31%.

Obliques

Located on the outer edge of the torso, the obliques are an important core muscle group. They are made up of the internal and external obliques, with the former sitting just underneath the latter.

While the glutes are the primary focus of clamshells, the obliques help prevent excessive rotation of the torso and pelvis. This stabilization ensures proper form and allows the glutes to engage more effectively.

The oblique muscles play an important role during many movements and contribute to a more toned midsection. Although clamshells aren’t the best option for strengthening these muscles, you can choose from plenty of oblique exercises.

Equipment

Bodyweight

Bodyweight

Requires bodyweight resistance and additional equipment for proper execution.

Variations

Exercises that target the same primary muscle groups and require the same equipment.

Donkey Kick

Cobra Stretch

Lying Glute Stretch

Bridge Kick

Glute Bridge March

Plank & Rear Kick

Curtsy Lunge with Towel

Who Should Do?

People With Weak Hip Muscles

Iliopsoas tightness is one of the most common causes of back pain. It occurs when the hip flexor muscles are weak, and the iliopsoas tightens to compensate for the lack of strength.

Weak hip muscles are a common issue, as many people spend their days sitting for work. When seated, the hip flexors are in their most relaxed state. They do not receive the workout necessary to remain strong and pliable.

Exercises like clamshells are a wonderful option for strengthening the iliopsoas to combat lower back pain. Additionally, they specifically target the gluteus medius and gluteus minimus. These muscles are essential for hip stability and strength. 

Athletes

Performing clamshells to strengthen the gluteus medius, minimus, and other hip flexor muscles can offer a wide variety of benefits. 

Strengthening these muscles is crucial for hip stability and injury prevention. It can also prevent conditions like knee valgus and lower back pain. 

As many as 27% of children suffer from knee valgus, a condition that affects proper knee alignment. It is exacerbated by sports that involve single-leg landings and a lack of gluteus medius and minimus strength.

Additionally, clamshells help strengthen the hip abductors, including the gluteus medius, minimus, and tensor fasciae latae muscles. These muscles are essential for improving lateral movements, agility, and overall athletic performance. 

Runners

Clamshells are effective for strengthening the gluteus medius, which is shown to improve pelvis stability and alignment while running. 

This can play an important role in reducing the risk of injuries related to running. Some of these include iliotibial band syndrome, runner’s knee, and hip pain — all common among runners.

Clamshells can also help to correct muscle imbalances in the lower body to prevent injury and running-related pain.

Who Should Not Do?

Lifters Seeking Hypertrophy

Hypertrophy training focuses on developing muscles, with the main goal of muscle growth. Lifters seeking hypertrophy gains will likely find clamshells ineffective because they target smaller muscles like the gluteus medius and minimus.

They are also usually a bodyweight exercise with very few options for incorporating weight. This means utilizing progressive overload to challenge the muscles through incrementally heavier loads will be difficult or impossible.

Clamshells are designed for stability and muscle activation rather than muscle growth. They should be used to improve the performance of exercises such as squats, deadlifts, and hip thrusts. 

These exercises, which engage larger muscle groups, allow for the loading necessary for muscle growth.

Individuals With Acute Lower Back Pain

Clamshells can improve chronic lower back pain by strengthening the gluteals and hip flexors. However, acute and chronic lower back pain differ greatly. Acute lower back pain, or targeted pain that has been present for less than six weeks, requires different treatment.

Clamshells should be avoided in these cases because the exercise can strain the lower back if performed incorrectly. Maintaining the correct position may also be difficult for those experiencing pain, leading to compensatory movements that could worsen the condition.

These individuals should focus on exercises that limit spinal movement, like bridges or isometric core exercises. However, these exercises should only be performed under the guidance of a licensed physical therapist.

Benefits Of Clamshells

Supports Posture

Clamshells help support posture by strengthening the gluteus medius and minimus muscles. These muscles are essential for stabilizing the pelvis to maintain proper alignment of the lower back and hips. 

Weaknesses in these muscles can cause the pelvis to tilt, a condition known as anterior pelvic tilt. Although a small degree of pelvic tilt is natural, too much can contribute to poor posture. This happens, in part, because of the limited range of motion through the hips and an overarching spine.

Additionally, clamshells engage the obliques, which are key core muscles. They promote core stability and an overall balanced, upright posture.

Improves Mobility

Mobility refers to the ability of a joint to move through its full range of motion pain-free and with control.

It involves a combination of flexibility and strength, which affect both passive and active range of motion. Joint mobility helps you perform pain-free movement patterns and is essential for daily activities and athletic performance.

Clamshells improve mobility by strengthening the gluteus medius, gluteus minimus, and iliopsoas muscles. These key hip muscles play important roles in hip stability to ensure proper alignment of the hip joint.

Relieves Tension

Physical therapists often use clamshells to help relieve tension in the hips and lower back. Weak or inactive gluteal muscles can lead to overcompensation by other muscles, resulting in muscle tightness. 

Clamshells help restore balance between underused and overactive muscles by activating and engaging the glutes. Relieving tension in these overworked areas is the key to alleviating lower back and hip tightness.

Frequently Asked Questions

What muscles do clamshells work?

The clamshell exercise primarily works the gluteus medius and minimus, key hip stabilization, and abduction muscles. It also engages the gluteus maximus, although to a lesser extent, as well as the hip flexors and obliques.

Can I do clamshells every day?

Generally, it’s not recommended to exercise every day, including clamshells. Instead, you should practice clamshells a maximum of four times a week, with a day’s rest between workouts.

Why are clamshells good?

Clamshells are beneficial because they strengthen the gluteals and hip flexors, which are crucial for posture, balance, and joint stability. By targeting these often neglected muscles, clamshells help prevent injuries like knee or lower back pain.

How many clamshells should I do?

Unless instructed by a physical therapist, most people can aim for 12 to 15 reps of clamshells on each side. Performing them with exercise bands or weights will help improve the exercise’s strength-building potential.

Resources

Endomondo.com refrains from utilizing tertiary references. We uphold stringent sourcing criteria and depend on peer-reviewed studies and academic research conducted by medical associations and institutions. For more detailed insights, you can explore further by reading our editorial process.

  1. Calatayud, J., Vinstrup, J., Jakobsen, M.D., Sundstrup, E., Brandt, M., Jay, K., Colado, J.C. and Andersen, L.L. (2015). Importance of mind-muscle connection during progressive resistance training. European Journal of Applied Physiology, [online] 116(3), pp.527–533. doi:https://doi.org/10.1007/s00421-015-3305-7.
  2. Schoenfeld, B.J., Grgic, J., Van, D.W. and Plotkin, D.L. (2021). Loading Recommendations for Muscle Strength, Hypertrophy, and Local Endurance: A Re-Examination of the Repetition Continuum. Sports, [online] 9(2), pp.32–32. doi:https://doi.org/10.3390/sports9020032.
  3. Dupuy, O., Wafa Douzi, Dimitri Theurot, Bosquet, L. and Benoit Dugué (2018). An Evidence-Based Approach for Choosing Post-exercise Recovery Techniques to Reduce Markers of Muscle Damage, Soreness, Fatigue, and Inflammation: A Systematic Review With Meta-Analysis. Frontiers in Physiology, [online] 9. doi:https://doi.org/10.3389/fphys.2018.00403.
  4. Jeong, S.-G., Cynn, H.-S., Lee, J.-H., Choi, S. and Kim, D. (2019). Effect of Modified Clamshell Exercise on Gluteus Medius, Quadratus Lumborum and Anterior Hip Flexor in Participants with Gluteus Medius Weakness. Journal of The Korean Society of Physical Medicine, [online] 14(2), pp.9–19. doi:https://doi.org/10.13066/kspm.2019.14.2.9.
  5. Kinney, A.L., Giel, M., Harre, B., Heffner, K., McCullough, T., Savino, M., Scott, A. and Barrios, J.A. (2021). Surface Electromyography of the Internal and External Oblique Muscles During Isometric Tasks Targeting the Lateral Trunk. Journal of Sport Rehabilitation, [online] 30(2), pp.255–260. doi:https://doi.org/10.1123/jsr.2018-0442.
  6. Lakkadsha, T.M., Qureshi, M.I., Kovela, R.K., Saifee, S.S. and Lalwani, S.S. (2022). Efficacy of Single Stretching Session of Iliopsoas Using Proprioceptive Neuromuscular Facilitation Versus Muscle Energy Technique on Low Back Pain in Patients With Lumbar Hyper-Lordosis. Cureus. [online] doi:https://doi.org/10.7759/cureus.27916.
  7. Bartosz Wilczyński, Katarzyna Zorena and Ślęzak, D. (2020). Dynamic Knee Valgus in Single-Leg Movement Tasks. Potentially Modifiable Factors and Exercise Training Options. A Literature Review. International Journal of Environmental Research and Public Health, [online] 17(21), pp.8208–8208. doi:https://doi.org/10.3390/ijerph17218208.
  8. Semciw, A., Neate, R. and Pizzari, T. (2016). Running related gluteus medius function in health and injury: A systematic review with meta-analysis. Journal of Electromyography and Kinesiology, [online] 30, pp.98–110. doi:https://doi.org/10.1016/j.jelekin.2016.06.005.
  9. Plotkin, D., Coleman, M., Van Every, D., Maldonado, J., Oberlin, D., Israetel, M., Feather, J., Alto, A., Vigotsky, A.D. and Schoenfeld, B.J. (2022). Progressive overload without progressing load? The effects of load or repetition progression on muscular adaptations. PeerJ, [online] 10, p.e14142. doi:https://doi.org/10.7717/peerj.14142.
  10. See, Q., Tan, B. and Kumar, D. (2021). Acute low back pain: diagnosis and management. Singapore Medical Journal, [online] 62(6), pp.271–275. doi:https://doi.org/10.11622/smedj.2021086.
  11. Suits, W.H. (2021). Clinical Measures of Pelvic Tilt in Physical Therapy. International Journal of Sports Physical Therapy, [online] 16(5). doi:https://doi.org/10.26603/001c.27978.
  12. M. Nannaparaju, S. Mortada, Wiik, A., Khan, W. and Alam, M. (2017). Posterolateral corner injuries: Epidemiology, anatomy, biomechanics and diagnosis. Injury, [online] 49(6), pp.1024–1031. doi:https://doi.org/10.1016/j.injury.2017.10.008.

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