Exercise guide · evidence-graded

Kettlebell Cossack Squat

The Cossack squat is a wide-stance, side-to-side squat: holding a dumbbell or kettlebell at your chest, you sit down onto one bent leg while the other stays straight out to the side, then push back to the middle. It works the bent leg's quadriceps and glutes and the inner-thigh (adductor) muscles through a deep range, and builds strength and control in a long side-to-side stretch.

Also called: KB Cossack Squat, Goblet Cossack Squat, Loaded Cossack Squat, Dumbbell Side-to-Side Squat · Equipment: kettlebell · Pattern: squat

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How to do it

Step by step

  1. Hold a dumbbell upright by one end, or a kettlebell by the horns, close to your chest with your elbows tucked in.
  2. Stand with your feet about twice shoulder-width apart and your toes turned slightly out.
  3. Shift your weight to one side and sit down onto that leg, bending the knee and sending the hips back. Keep the whole foot of the bent leg flat.
  4. Let the other leg straighten out to the side, rolling onto its heel so the toes point up.
  5. Sink as deep as you can while the bent-leg heel stays down, your chest stays up and the bent knee tracks over the toes.
  6. Drive through the whole foot of the bent leg to push back up to the middle.
  7. Alternate sides each rep, or finish all reps on one side before switching.
Coaching cues
  • Sit down onto one heel
  • Straight leg, toes to the ceiling
  • Chest up behind the weight
  • Bent knee over the middle toes
  • Push the floor away back to the middle

In VALDA, these cues are one tap away on the exercise while you train.

Muscles worked

What it trains

MuscleRoleEvidence
Quadriceps: vastus lateralisPrime moverC
Quadriceps: vastus medialisPrime moverC
AdductorsPrime moverC
Gluteus maximusPrime moverC
Gluteus medius/minimusStabiliserC
Erector spinaeStabiliserD
SoleusStabiliserD

Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.

Common faults

What goes wrong, and the fix

Heel lifting on the bent leg

Fix: Sink only as deep as the bent-leg heel stays flat on the floor.

Chest folding over the weight

Fix: Hold the weight tight to your chest and keep your chest up as you sink.

Bent knee caving inward

Fix: Push the bent knee out so it tracks over the middle toes throughout.

Stance too narrow

Fix: Widen the stance to about twice shoulder width before the first rep.

Bouncing at the bottom

Fix: Pause for a moment at the bottom, then drive back up under control.

Rushing the side-to-side shift

Fix: Move slowly and reach your full depth on each side before switching.

Programming

What the research says

Muscle growthRehab & prehabGeneral fitnessSport performanceEnduranceFat loss & conditioning

  • Range of motion — A meta-analysis found full-range training built more leg muscle and strength than partial-range training, and a 10-week squat study found full-depth squats grew the glutes and inner thighs more than half squats.
  • Mobility — A meta-analysis of 11 trials found strength training improved joint range of motion about as much as stretching, with no statistical difference between them.
  • Load — The Cossack squat is usually trained with light to moderate weights. Research comparing loads finds muscle growth is similar across a wide range of loads when sets are taken close to failure.
  • Effort — Studies show sets that finish a few reps short of failure capture most of the growth benefit, and true failure adds only a small extra return.
  • Frequency — Training a muscle about twice a week has been associated with more growth than once a week. Many lifters use the Cossack squat as a regular accessory or warm-up movement.
Alternatives · VALDA FLEX

Swap it mid-workout

With VALDA Pro, FLEX offers alternatives like these when you swap an exercise mid-workout.

Log the kettlebell cossack squat in VALDA, with these cues one tap away while you train and your history for it in one place.

General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.