How is a skater squat different from a pistol squat?

In a skater squat the free leg folds behind you and the back knee lowers toward the surface, while in a Pistol Squat the free leg is held straight out in front. The skater squat allows more forward lean and asks for less hip flexor strength and ankle mobility, so most people find it easier to learn.

Why do the arms reach forward?

As the hips move back, the arms move forward to keep your center of mass over the working foot. Without that counterbalance, most people either fall backward or stay too upright to reach full depth.

Should the dome or the flat side face up?

This exercise uses the dome side up, which gives the foot a rounded, springy surface that moves under you. Turning the BOSU over, as in the BOSU Single-Leg Squat (Flat Side Up), puts you on a platform that can tilt in any direction, which many people find harder to balance on.

How many reps should I do?

Most people do 2 to 4 sets of 5 to 10 slow reps per leg, stopping each set while every rep is still controlled. Start with your weaker leg and match its reps on the stronger side.

Can I hold weights for this exercise?

You can hold a light dumbbell or plate out in front as extra counterbalance once bodyweight reps are steady, but heavy loading is not the point. Force output drops on an unstable surface, so build single-leg strength with stable-ground exercises like the Dumbbell Bulgarian Split Squat and keep this one for balance and control.

BOSU Skater Squat

What Is the BOSU Skater Squat?

BOSU Skater Squat is a compound exercise that primarily targets the quadriceps and also engages the glutes, adductors and the stabilizers of the lower leg. It is an advanced-level movement: you stand on one foot on the dome side of a BOSU, fold the free leg behind you and lower until the back knee nears the dome, reaching the arms forward as a counterbalance.

The skater squat is a popular single-leg squat because the free leg trails behind the body instead of being held out in front, as it is in a Pistol Squat. That lets the torso lean forward and the hips sit back, so the working leg shares the load between the knee and the hip. Adding the BOSU turns it into a strength and balance drill at once: the dome shifts under the foot on every rep, and the ankle, foot and hip have to keep correcting it. In a study of 15 healthy, active adults, the soleus in the calf worked harder during a standard single-leg squat on a BOSU than on flat ground, though the skater squat itself was not part of that test.

The quadriceps do most of the work as the knee bends and straightens. The glutes grow more involved the further the hips travel back and the more the chest tips forward, and the gluteus medius works throughout to stop the knee from caving in and the pelvis from dropping. A deeper range, with the back knee close to the dome, loads the hip more, while a shorter range keeps the work mostly in the quads.

Because an unstable surface limits how much force you can produce, this is not the version to build maximal leg strength. It fits best as a balance and single-leg control exercise for people who already own a solid skater squat on the floor, such as field and court athletes, skiers and skaters, or anyone returning to single-leg work who has the base strength for it. If it is too hard, build up with the BOSU Squat, the BOSU Single-Leg Stand and a regular skater squat on stable ground before combining the two.

Muscles Worked

MuscleActivation

Vastus Lateralis: Primary
Vastus Medialis: Primary
Gluteus Maximus: High
Gluteus Medius: High
Rectus Femoris: High
Adductor Magnus: Medium
Peroneus Longus: Medium
Soleus: Medium
Biceps Femoris: Low
Erector Spinae: Low

Instructions

Place a BOSU dome side up on a non-slip floor and stand on it with one foot in the center of the dome.
Bend the other knee and lift that foot behind you so the shin points back, with your arms relaxed at your sides.
Find your balance with the whole working foot pressed into the dome and your eyes on a fixed point ahead.
Push your hips back and bend the working knee, letting your chest tip forward as you lower.
Reach both arms forward as you descend to keep your weight over the middle of the foot.
Keep the working knee tracking over your middle toes and lower until the back knee is just above the dome.
Pause briefly without touching the back knee down.
Drive through the whole foot to stand back up, bringing the arms back to your sides as you straighten.
Finish all reps on one leg, then switch sides.

Common Mistakes

Knee caving inward
Letting the working knee collapse toward the midline stresses the knee and usually means the hip is not doing its share, so push the knee out over the middle toes.
Foot off center
Standing near the edge of the dome makes it tip, so place the foot in the middle before lifting the other leg.
Heel lifting
Rising onto the ball of the foot shifts weight forward and makes the dome harder to control, so keep the whole foot pressed down.
Dropping into the bottom
Falling into the lowest position loses balance and control, so lower slowly and stop before the back knee touches the dome.
Rounding the back
Reaching the arms forward is meant to balance a hip hinge, not to fold the spine, so keep the chest open and the back long as you lean.
Too much depth too soon
Chasing full range before you can control it on the BOSU leads to wobbling and knee strain, so start with a shorter range and build depth gradually.

Injuries

BOSU Skater Squat is a medium risk exercise when performed with proper technique. The working knee takes your full body weight through a deep range, and the dome can tip or roll the ankle if the foot drifts off center. The most likely problems are front-of-knee irritation, an ankle sprain from a sudden loss of balance, and a fall off the BOSU.

The knee is most at risk when it caves inward or when you drop too fast into the bottom. Keep the knee tracking over the middle toes, place the foot in the center of the dome, and lower under control. Set the BOSU on a non-slip floor with clear space around it, and keep a wall, rack or partner within reach until you can finish every set without stepping off.

To make it easier, shorten the range so the back knee stops well above the dome, or practice the skater squat on the floor first. The BOSU Squat and the BOSU Single-Leg Stand build the balance side, while the Dumbbell Bulgarian Split Squat builds single-leg strength on stable ground. Once you can control full-depth reps, progress by slowing the lowering phase or pausing at the bottom rather than by adding heavy load.

Stop the set if you feel sharp pain in the knee or ankle, if the knee keeps collapsing inward, or if you keep stepping off the dome to catch yourself. Anyone with a recent ankle sprain or knee pain should get cleared before training single-leg work on an unstable surface.

Overview

Primary Focus: Quads
Equipment: Balance trainer and body weight
Modality: Strength
Difficulty: Advanced

Alternative Exercises

Frequently Asked Questions

Q: How is a skater squat different from a pistol squat?: In a skater squat the free leg folds behind you and the back knee lowers toward the surface, while in a Pistol Squat the free leg is held straight out in front. The skater squat allows more forward lean and asks for less hip flexor strength and ankle mobility, so most people find it easier to learn.
Q: Why do the arms reach forward?: As the hips move back, the arms move forward to keep your center of mass over the working foot. Without that counterbalance, most people either fall backward or stay too upright to reach full depth.
Q: Should the dome or the flat side face up?: This exercise uses the dome side up, which gives the foot a rounded, springy surface that moves under you. Turning the BOSU over, as in the BOSU Single-Leg Squat (Flat Side Up), puts you on a platform that can tilt in any direction, which many people find harder to balance on.
Q: How many reps should I do?: Most people do 2 to 4 sets of 5 to 10 slow reps per leg, stopping each set while every rep is still controlled. Start with your weaker leg and match its reps on the stronger side.
Q: Can I hold weights for this exercise?: You can hold a light dumbbell or plate out in front as extra counterbalance once bodyweight reps are steady, but heavy loading is not the point. Force output drops on an unstable surface, so build single-leg strength with stable-ground exercises like the Dumbbell Bulgarian Split Squat and keep this one for balance and control.