For a calf raise on a Bosu, you stand on the soft dome of a Bosu ball (a half ball balance trainer with a flat base) and rise onto your toes. Go as high as you can without losing your balance, then come back down. The dome keeps shifting, so your feet and ankles never stop making small corrections. The voice guide says you can hold a stable object, and the app lists this version as done with support. Physios tend to bring it in later in ankle rehab, once calf raises on a firm floor feel steady.

How to do the calf raise on a bosu

Set the Bosu dome side up on a non-slip floor, right next to a wall, kitchen counter or sturdy rail you can hold without reaching. Clear the space around it.
Hold your support and step onto the middle of the dome with one foot, then bring the other foot up beside it, about hip width apart or a little closer.
Stand tall with your knees straight but not locked, and rest your hands on the support in front of you. In the video her hands are raised in front of her chest, as if resting on a wall.
Rise onto the balls of your feet, as high as you can while staying balanced, and hold for a few seconds at the top. In the video she holds the top position for about 5 seconds.
Lower your heels slowly back onto the dome and let the wobbling settle before the next rise.
When you finish, keep hold of your support and step down one foot at a time.

What you should feel

Work in both calves, with a lot of small, quick adjustments in your feet and ankles as the dome moves under you.

Common mistakes

Letting go of the support before you are steady on the dome.
Rolling onto the outer edges of your feet as you rise, so the ankles tip outward.
Bouncing up and down quickly instead of rising and lowering with control.
Standing near the edge of the dome, where it tilts the most.

How often

Many programs start with 1 to 3 sets of 6 to 10 rises, holding each for 3 to 5 seconds at the top and keeping hold of your support, a few days a week. Your physio will adjust this.

Stop and check with your physio if

A sudden pop or snap at the back of your ankle or heel, a feeling that someone kicked you there, or sudden pain there after which you cannot push off or rise onto your toes on that leg. Stop, take the weight off that leg carefully and go to an urgent care center or emergency department the same day, even if you can still walk, as this can be a torn Achilles tendon.
You feel dizzy, lightheaded, faint or sick, or the room seems to spin. Hold your support, sit down and get medical advice the same day before you practice again. If you faint, it does not settle within a few minutes of sitting still, your vision suddenly blurs or goes double, or you cannot stand or walk steadily, call emergency services.
The ankle rolls or gives way, or sharp pain starts in the ankle, heel or calf.
You feel unsteady enough that you might fall, even holding your support. Keep hold, step down carefully and rest.
Your calf or thigh becomes swollen, warm, tender, red or darker than usual, or has a throbbing or cramping pain that feels different from normal muscle ache. Stop and get medical advice the same day, as this can be a blood clot. If you are also short of breath or have chest pain, call emergency services.

From the clinic

The person in the video is barefoot. Wear flat shoes that fit well and grip the floor, not socks, tights or bare feet. Keep a hand on your support for every rise, and hold it firmly while you step on and off the dome. If you have fallen in the past year, often feel unsteady, take medicine that can make you dizzy, have low bone density (osteoporosis) or are pregnant, ask your physio whether you are ready for an unstable surface, and practice only when another adult is at home.

A sudden loss of balance is different. Call emergency services straight away for any sign of a stroke, even if it goes away: sudden dizziness with unsteadiness or falling over, a face that droops on one side, an arm you cannot lift or keep up, slurred or muddled speech, weakness or numbness on one side of your body or face, sudden blurred vision, double vision or loss of sight, or a sudden severe headache.

The usual path is calf raises on a firm floor first, then just standing on the dome while you hold on, and only then the rise. The BOSU squat uses the same setup to work the thighs. After an ankle fracture or ankle surgery, follow your surgeon's or physio's weight-bearing plan, and start this exercise only when they have cleared you. After an Achilles tendon repair, calf work on a wobbly surface comes late, so wait until your surgeon and physio agree the tendon is ready. Go gently after an ankle sprain, because the dome can tip the ankle the way it rolled.

Written and checked by the PocketPhysio editorial team. Last updated 2026-09-26.

This page is general education, not a diagnosis or a personal treatment plan. If you have pain, an injury or a health condition, see a physiotherapist or doctor before starting new exercises.

Calf raise on a Bosu