Single-Leg High Box Squat
The single-leg high box squat has you lower under control onto one leg down to a box or bench set roughly knee height, then stand back up on that same leg. The raised surface shortens the range compared to a full single-leg squat, which makes it a realistic starting point for most people. It builds the strength, balance, and confidence needed before progressing to deeper single-leg squat variations.
Why it works
Standing on one leg immediately removes the support your other leg normally provides, so your quadriceps, glutes, and hamstrings all have to work harder to control the descent and drive you back up without help. Your quadriceps handle most of the knee extension on the way up, while your glutes and hamstrings control your hip and keep your knee tracking properly over your foot. Because the box sets a consistent depth, it also gives you an external check on your range, useful feedback that a freestanding single-leg squat doesn't offer.
Set up
- Stand in front of a sturdy box or bench set at roughly knee height, facing away from it.
- Lift one foot off the floor and extend it slightly forward, balancing on the standing leg.
- Reach your arms forward or out to the sides for balance.
- Keep your standing knee soft, not locked, before you begin.
How to do it
- Bend your standing knee and hip to lower yourself down toward the box.
- Keep your torso fairly upright as you descend, hinging only slightly forward.
- Touch your glutes lightly to the box without fully sitting your weight down.
- Drive through your standing foot to push back up to a full standing position.
- Complete all reps on one leg before switching sides.
Form cues
- Keep your standing knee tracking over your toes, not caving inward.
- Reach your arms forward as a counterbalance instead of fighting to stay upright without them.
- Control the descent, don't drop onto the box.
- Drive through your whole foot, not just your toes, on the way up.
Breathing: Inhale as you lower toward the box, and exhale as you drive back up to standing.
Common mistakes
Letting the standing knee collapse inward during the descent.
Fix: Actively push your knee out over your toes as you lower, and slow down if it starts to cave.
Fully sitting all your weight down onto the box between reps.
Fix: Touch lightly and keep tension in your leg so the muscle stays under load throughout the set.
Leaning far forward at the hips to make the squat easier.
Fix: Keep your torso more upright and use your arms for balance instead of bending forward from the waist.
How to program it
- This is a single-leg compound movement, so 2 to 3 sets of 6 to 10 reps per leg is a solid starting range.
- Once or twice a week is enough for most people, since single-leg squatting patterns tax balance and stabilizers in a way that needs real recovery time between sessions.
- Lower the box height gradually over weeks as your strength and control improve, rather than jumping straight to a deeper range.
Safety notes
- Use a box height you can control confidently, if you're wobbling badly or falling to one side, raise the box until your balance catches up.
- Keep a wall or sturdy surface within reach the first few sessions in case you need to catch your balance.
Exercise profile
- Force
- Push
- Mechanics
- Compound
- Category
- Strength
Frequently asked questions
How many reps of the single-leg high box squat should I do?
2 to 3 sets of 6 to 10 reps per leg is a good starting point, focusing on control rather than speed.
What can I use as a box if I don't have one at home?
A sturdy chair, a step stool, or the bottom stair of a staircase all work, as long as the surface is stable and roughly knee height.
Single-leg high box squat vs pistol squat, how are they different?
A pistol squat takes you all the way to the floor on one leg with your other leg extended in front, demanding far more ankle mobility, strength, and balance. The high box version shortens that range, making it a realistic step before attempting a full pistol squat.
Why does my knee wobble during single-leg squats?
Wobbling usually means your hip and ankle stabilizers haven't caught up to your quad strength yet, which is common early on. Slow the tempo down, use a higher box, and keep practicing, the wobble typically settles within a few weeks of consistent work.