Cossack Squat: Form, Foot Position and a 5-Stage Progression

The Cossack squat is a side-to-side squat done from a very wide stance. You sink as deep as you can over one bent leg while the other leg stays straight, usually rolled onto its heel with the toes pointing up, then stand and switch sides. It builds one-leg strength in a deep position and stretches the inner thighs under load. Start with 1 to 2 sets of 5 per side as a warm-up, and build to 3 sets of 10 slow reps per side before you add real load.

This guide covers what the exercise trains, how to set up and do it, the toes-up question, what 28 published guides recommend, what the research does and does not show, a readiness test and a five-stage progression.

What the Cossack squat trains

The two legs do different jobs at the bottom of the rep.

We found no published study that measured muscle activity in the Cossack squat itself (more on that below). The table is based on the joint positions, not on lab data.

How to do a Cossack squat

1. Set your stance. Stand with your feet about twice shoulder-width apart, toes turned out slightly. You will fine-tune the width after the first rep.
2. Shift and sit. Move your weight over your right foot and sit your hips down and back, bending the right knee. Keep the right heel flat and the knee pointing the same way as the toes.
3. Straighten the other leg. As you go down, the left leg straightens. Roll it onto its heel so the toes point up (see the next section).
4. Go as deep as you can control. Stop when your heel starts to lift, your chest starts to drop toward the floor or your lower back rounds. Depth comes with time.
5. Stand back up by pushing through the whole right foot until you are back in the wide stance. Then switch sides. Count reps per side.

Fine-tuning the width. At the bottom, the straight leg should be fully straight. If it stays bent, widen your stance. If you cannot shift your weight over the working foot without your heel coming up, bring your feet in a little.

Arms. Clasp your hands at your chest or reach them straight out in front. Reaching forward moves your center of mass forward and makes it easier not to fall backward.

Toes up or foot flat?

Guides handle the straight leg in different ways. Of the 28 we reviewed, 19 teach rolling the straight leg onto its heel with the toes pointing up as the standard. Two treat it as optional: Catalyst Athletics lets the foot roll onto the heel and says you will need less of that as your mobility improves, and Boxlife Magazine suggests rotating the leg if the stretch is too strong. The other seven do not say.

What changes between the two:

That trade comes from the guides themselves: BarBend, Athlemove and others report that turning the toes up shifts part of the stretch from the adductors to the hamstrings. It is a coaching observation, not a measured result. Both versions are valid. Pick one and keep it the same so your depth is comparable from session to session.

What 28 Cossack squat guides recommend

We collected 28 English-language Cossack squat guides from Google’s US results and related searches on 31 October 2026 and coded what each one tells readers to do.

Three things stand out:

• Rep advice is consistent. Of the 13 per-side ranges, 11 fall within 5 to 10 reps per side, and five guides say exactly “5 to 10”. Healthline and Greatist both suggest 3 sets of 10 reps with 5 on each leg.
• Almost nobody gives a number for when to move on. Only one guide (PowerliftingTechnique) gives a number: 3 sets of 15 per leg with bodyweight before adding weight. The progression below gives a target for every stage.
• The research links are borrowed. The seven guides that link studies cite work on squat depth, lunge loading, stretching, range of motion, adductor training and muscle growth. None of the linked studies tested the Cossack squat.

Where guides split their advice by goal, this is what they say (reps per side unless noted):

The warm-up and stage targets in this guide sit inside those ranges. What is missing is a decision rule: only one of the 28 guides gives a number for when to move on. The readiness test and the stage targets below fill that gap.

How we got this. We took 32 guide URLs from the Google US results for “cossack squat” (via DataForSEO) and four related web searches, excluding video and social posts. Four pages could not be fetched (one 404, one server error, two blocked our script) and were dropped, leaving 28. Each page’s text was saved and coded by hand for the items above. The data covers one day of search results; guides change, and coding free text involves some judgment. With 28 pages, read these as counts, not percentages of all guides.

What the research shows

A PubMed search for “cossack squat” on 31 October 2026 returned one record, and it was about rhythmic gymnastics, not the exercise. If a page quotes precise muscle-activation percentages for the Cossack squat, ask which study they come from. The closest evidence is about related movements:

The fair summary: the Cossack squat trains deep, loaded range of motion, and that kind of training does improve flexibility and build muscle at long lengths in studies of similar exercises. The bodyweight-only result is a non-significant subgroup finding, not proof that bodyweight work fails, but it suggests bodyweight alone may not be enough if mobility is your main goal. That is one reason stage 5 below adds load, and stage 3 can use a light weight.

If you have a history of groin strains, the Copenhagen adduction is the exercise with trial evidence; the Cossack squat can sit alongside it, not replace it.

Find your starting stage

After a warm-up, test in this order and stop at the first step you cannot pass:

1. Side lunges. Do 3 sets of 10 per side, stepping out from feet together to thigh-parallel with the heel down. Cannot do all 30 clean reps per side: start at stage 1.
2. Supported depth. Holding a door frame, take a wide stance and do 5 reps per side. You pass if you reach full depth (hip below knee, heel down) with only fingertip support. If you need to hold on harder than that, or cannot reach full depth yet: start at stage 2.
3. Free depth. Do 5 reps per side with your hands clasped at your chest. If you fall backward, your chest drops toward the floor or you miss full depth: start at stage 3. If all 5 reps per side reach full depth under control: start at stage 4.

Test both sides and start at the stage of your weaker side.

The five-stage progression

Train it two or three times a week. Do 3 sets per side with 60 to 90 seconds of rest between sets. Move up when you hit the target for all three sets on both sides with clean reps: heel down, knee in line with the toes, chest up. Full depth means your hip below your knee.

These targets are our own coaching rules, set so each stage builds the strength and depth the next one needs. No study has tested them.

Stage 1: Side lunge. Start with your feet together, take a big step to the side, bend that knee until the thigh is about parallel to the floor, and push back to the start. It teaches the sideways weight shift with much less depth.

Stage 2: Supported Cossack squat. Hold a door frame, a post, a sturdy railing or suspension straps and do the full movement. Let your hands take as little weight as you need, and work at the depth you can control. Over the weeks, hold more lightly until your fingertips are only there for balance.

Stage 3: Counterbalance Cossack squat. Reach your arms straight out in front, or hold a light weight at your chest: a small dumbbell, a water jug or a filled backpack hugged to your chest. Twelve of the 28 guides recommend a weight held in front. It feels backward, but the weight in front keeps you from tipping backward at the bottom.

Stage 4: Bodyweight Cossack squat. Hands clasped at your chest, take three seconds to lower and stand up at a normal pace. The slow lowering keeps you from dropping into the bottom and bouncing out.

Stage 5: Loaded Cossack squat. Hold a heavier weight at your chest, the way you would for a goblet squat: a dumbbell, a kettlebell or a backpack with books. Pick a load that allows about 8 clean reps per side, build to 3 × 12, then add a little more. Our guide to weighted calisthenics covers the options for loading at home.

If your ankle is the limit. If your working heel lifts before your hip drops below your knee at any stage, put a small plate or a thick book under that heel. It reduces how far the ankle has to bend. Lower the lift over a few weeks as your ankle loosens.

Common mistakes and how to fix them

Where it fits in a workout

As a warm-up. One or two sets of 5 per side, slow and well short of your deepest range, before squats or a leg session. Our calisthenics warm-up is a good place to add it.

As a main exercise. On a leg day, put it after your main knee-dominant exercise such as the Bulgarian split squat, and pair it with a hamstring exercise like the Nordic hamstring curl. In a push, pull, legs split, it fits on leg day as a side-to-side movement.

On the pistol squat path. The Cossack squat and the pistol squat both need deep one-leg strength and ankle range. Our calisthenics leg workout lays out the pistol progression; the Cossack squat works well alongside it as a way to spend time in the deep position.

Frequently asked questions

What do Cossack squats work?

The bent leg does the strength work: quads, glutes and the inner-thigh adductors. The straight leg gets a loaded stretch through the adductors and hamstrings. The working ankle also has to bend a long way to keep the heel down, which is why tight ankles are a common limit.

What is the difference between a Cossack squat and a side lunge?

A side lunge starts with the feet together, steps out, stops around thigh-parallel and steps back in. A Cossack squat starts in a wide stance, the feet stay put, and you sink as deep as you can over one leg, usually with the straight leg rolled onto its heel. The side lunge is the easier pattern and a good first stage.

Should your toes point up in a Cossack squat?

Most guides say yes: 19 of the 28 we reviewed teach rolling the straight leg onto its heel with the toes up. Two treat it as optional, and seven do not say. Use toes up as the standard version, and a flat foot if you want more inner-thigh stretch and less hamstring stretch.

How often should you do Cossack squats?

Two or three times a week works for most people: as a short warm-up set before leg training, or as a main exercise on a lighter leg day. No study has tested a best frequency for this exercise, so treat that as a practical starting point.

Are Cossack squats good for beginners?

The full version is hard for most beginners because it needs deep hip, knee and ankle range at the same time. Start with side lunges or a supported Cossack squat holding a door frame, and use the readiness test in this guide to find your stage.

How many reps of Cossack squats should I do?

As a warm-up, 1 to 2 sets of 5 per side. As a strength exercise, build to 3 sets of 10 slow reps per side with bodyweight, then add load. Most published guides land between 5 and 10 reps per side.

Sources

• Alizadeh S, Daneshjoo A, Zahiri A, et al. Resistance training induces improvements in range of motion: a systematic review and meta-analysis. Sports Medicine, 2023.
• Kubo K, Ikebukuro T, Yata H. Effects of squat training with different depths on lower limb muscle volumes. European Journal of Applied Physiology, 2019.
• Delmore RJ, Laudner KG, Torry MR. Adductor longus activation during common hip exercises. Journal of Sport Rehabilitation, 2014.
• Harøy J, Clarsen B, Wiger EG, et al. The Adductor Strengthening Programme prevents groin problems among male football players: a cluster-randomised controlled trial. British Journal of Sports Medicine, 2019.
• Guide survey data: 28 Cossack squat guides collected 31 October 2026, coded by bestcalisthenicsworkout.com. Guides referenced by name: Catalyst Athletics, Boxlife Magazine, BarBend, Athlemove, Healthline, Greatist, PowerliftingTechnique, Steel Supplements, Set For Set, Julie Lohre, Falsegrip, Runlovers.