How to Do Swiss Ball Leg Curls (Form & Benefits)

The Swiss ball leg curl, aka Swiss ball bridge hamstring curl, is a challenging and technical exercise that effectively isolates the hamstring muscles located on the back of your thighs. It is a bodyweight exercise, and therefore, appropriate for nearly every fitness level.

Resistance training does an exceptional job of training the body in almost every movement pattern. However, it isn’t effective for complete hamstring training to benefit both hip extension and knee flexion, the two functions of the hamstrings.

The Stability Ball Hamstring Curl is a simple but effective exercise to strengthen your glutes, core muscles, and hamstrings. Most common lower body exercises like Romanian deadlifts, good mornings, lunges, and squats primarily work the quads, glutes, and the hamstrings’ action to ensure proper hip extensions, with almost zero focus on knee flexion.

In contrast, the Swiss ball leg curl move uses the stability ball to create instability, forcing you to tighten your core and stabilize your body. If you incorporate the Stability Ball Hamstring Curl into your exercise routine, you will certainly feel it in your legs the following day.

The greatest challenge you are likely to face with this form of exercise is balancing. You have to maintain your balance on an exercise ball while executing the leg curl. Although it takes patience to master this exercise’s range of motion, there is no doubt that once you do, you will have optimum results in the coordination, strength, and appearance of your legs.

Muscles worked by Swiss Ball leg curls

If your typical leg day consists of just a few general moves spread between the squat rack and seated leg curls and lying leg curls done on a leg curl machine, you're leaving loads of potential gains out there on the gym floor.

A full-on lower body workout should include exercises focused on giving more specific muscle groups some extra love. Since they're so essential for explosive, powerful movement, hamstrings are a prime candidate for special attention. 

The Swiss ball hamstring curl is excellent because your entire body is forced to engage, even though the knee is the only joint you'll be moving. However, your core and your glutes will be in overdrive working to stabilize your hips in balancing your lower back on the wobbling ball.

Targeted Muscles

Although the Swiss ball hamstring curl is one of many curl variations, it is a splendid option for bodybuilders and lifters as part of their strength training routines. In addition to adding strength to your hamstrings, stability ball leg curls also benefit other muscle groups in both the upper and lower legs.

1. The popliteus in the knee

2. The gastrocnemius in the calf

3. The sartorius and gracilis in the thigh

These muscles work together with the hamstrings allowing the knee to bend when curling the exercise ball.

Furthermore, muscles in the ankles, hips, and torso are activated to help you maintain balance on the stability ball, including:

4. The erector spinae

5. The abdominal muscles

6. The glutes

7. The tibialis anterior or shin muscles

Most importantly, to achieve maximum benefit and remain injury-free during the activation of all these muscle groups, proper form during the exercise is vital.

How to do Swiss Ball leg curls with proper form

Swiss ball leg curls are also known as supine hip extensions with leg curls or SHELC for short, and although they look easy to do, you’re in for a surprise when you first try them.

Starting position:

All you will need for this hamstring exercise is a stability ball and enough space to lie on your back. Lie face-up and let both legs rest on the Swiss ball. Your calves and heels must be on the ball. Place your hands beside you on the floor for greater stability. Brace your core, squeeze your glutes, and lift your hips to form a bridge. Your feet, hips, and lower and upper body should create a straight line.

1. Maintain this elevated bridge position and use your feet to roll the ball toward your glutes by flexing your knees and hips as your heels pull the ball in a smooth, controlled movement toward your butt.

2. When you can’t pull the ball any closer to your glutes, slowly straighten your legs as you use your heels to return the ball to the start position.

3. When you reach the number of reps per set, lower your back to the floor before proceeding with the next set.

When it comes to your rep sets, your personal trainer or physical therapist can recommend how many repetitions you should start with, and how you should build up from there. It’s always advised to start out slowly and increase reps as you progress and master the proper form.

The typical initial aim is to work up to 2 or 3 sets of 8 to12 reps per set. However, don’t force it—If you experience back pain or become fatigued, cut back on the reps or take a break between sets.

What are the benefits of Swiss ball leg curls?

Leg curls are functional exercises that become more challenging when done with stability balls because your muscles have to work harder for each movement. This instability makes the movement more reactive and harder to control.

Below are additional benefits of doing stability ball hamstring curls.

1. To maintain proper form throughout the full range of movement, the smaller stabilizing muscles in your lower half are automatically activated.

2. Though many lower-body moves focus on working bigger muscles, like the quads and glutes, strengthening these smaller muscles is essential for helping to support your joints and control your movements during various exercises.

3. Swiss ball leg curls target your core and improve your stability, balance, and agility, enhancing your performance in various activities such as tennis, Yoga, dance, football, and many day-to-day activities.

4. Swiss ball leg curls can increase your metabolic rate which can help you burn fat faster.

5. Stability ball hamstring curls can also be done as pre- or post-workout exercises.

Unilateral Swiss Ball Leg Curls

If you are ready to tackle more challenging Swiss ball leg curls, unilateral or single-leg curls are executed using the power of just one leg. Working one side of the body at a time increases the intensity of the movement by forcing each leg to do all the work. This requires elevated degrees of focus, coordination, strength, and balance to repeat single-leg reps with perfect form.

Furthermore, unilateral moves, like these single-leg hamstring curls, are helpful to identify and correct any muscle imbalances. Left unchecked, such imbalances could lead to preventable injuries.

How to do single-leg Swiss ball hamstring curls:

Here you will use only one leg at a time, but you’ll also change your arm position to make the leg curls more challenging.

The starting position for this unilateral version is the same as for the basic exercise ball leg curls, with your body in an elevated bridge position with both lower legs on the ball forming a straight line from your heels to your shoulders. However, here you must place your arms by your sides but flexed at the elbows and your forearms just above the floor surface.

1. Lift your right foot, flex your foot and raise it straight in the air.

2. Squeeze your glutes, push your left heel down on the ball, and raise your hips as high as possible.

3. Slowly pull the ball in toward your body using a strong, flexed foot as you bend your left knee and continue to push your hips up throughout the curl, and remember to keep your forearms off the floor throughout.

4. When the Swiss ball is as close to your butt as you can manage, pause for a moment before slowly reversing the movement.

5. Push with your left heel to return to the starting position. Keep your hips elevated throughout this portion as well.

6. This is 1 rep. Aim for 8 to 10 reps with one leg, then lower your body to the floor, relax for a moment and return to the elevated position to do the reps with the other leg.

Beginners are advised to start with the basic double-leg Swiss ball leg curl. Once they have mastered multiple sets of 8 or 10 reps, they can attempt the single-leg version.

The bottom line

Both the single- and double-leg Swiss ball hamstring curls will be valuable additions to your lower body workout routine, adding strength and stability.

Although this exercise is normally considered a safe option, it can have severe consequences for individuals with a history of hip, knee, or back conditions. The movement and positioning can aggravate these conditions. It’s always best to consult your physical therapist or physician before starting a new exercise.

Furthermore, men and women who seek a clinically backed pre-workout boost might want to try PRE.

Whether new to the pre-workout game or a seasoned vet, PRE can provide everything you need to break plateaus and get the most out of every workout.  Read the Science behind PRE by Dr. Paul Henning.