A ball plank knee tuck is a high plank with your lower shins and ankles resting on an exercise ball, where you draw one knee in under your hips, return it to the ball and switch legs. With only one leg on a ball that can roll, your stomach and trunk muscles work hard to keep your hips level and the ball still. Your shoulders carry much of your weight throughout. It usually follows a steady plank with both legs on the ball.

How to do the ball plank knee tuck

Kneel behind an exercise ball, lean over it and walk your hands forward until the ball rests under your lower shins and ankles, as in the video.
Settle into a plank on straight arms with your hands under your shoulders and your body in one line from head to feet. Tuck your chin a little and keep your back flat, not arched.
Gently tighten low in your tummy and lift your pelvic floor a little, about a quarter of your full effort, then keep breathing steadily.
Lift one leg off the ball and bend it, bringing the knee in under your hips, while the other leg stays on the ball. Pause there, keeping the ball still.
Straighten that leg back onto the ball, steady yourself, then tuck the other knee.
To finish, walk your hands back toward the ball and lower your knees to the floor.

What you should feel

Steady effort across your stomach and around your trunk, work at the front of the hip as the knee comes in, and plenty of load through your shoulders and arms.

Common mistakes

Hips rising or twisting as the knee comes in.
The lower back sagging while one leg is off the ball.
Rushing the tuck so the ball rolls off to one side.
Holding your breath during each tuck.

How often

Many programs start with 2 to 3 sets of 4 to 8 tucks on each leg, resting between sets, a few days a week. Your physio will adjust this.

Stop and check with your physio if

Pain in a wrist or shoulder, or tingling running down an arm into your hand.
Pins and needles in your arm or hand that do not go away after you stop, or part of your arm or hand goes numb. Get medical advice the same day. If one side of your face or body suddenly goes numb or weak, or your speech becomes slurred or muddled, call emergency services, even if it goes away.
A lower back ache that starts or grows during the set.
A sharp pinch at the front of the hip as the knee comes in.
Chest pain or pressure, dizziness or feeling faint, a racing or irregular heartbeat, or being far more out of breath than the effort should cause.

From the clinic

Hold a steady plank with feet on a ball for several slow breaths before you add the tuck. Resting the ball under your shins, closer to your knees, makes the plank easier, while resting it under your ankles makes it harder. If the ball is still hard to control, practice slow mountain climbers on the floor first.

Choose an anti-burst exercise ball that is firmly inflated, on a floor that does not slip, with space on each side in case you roll off. If the ball starts to slide away, drop your knees to the floor and let it go. Check with your physio first if you have fallen in the past year, have thin bones (osteoporosis), or find getting down to the floor and back up hard.

Your hands and shoulders take a large share of your weight. Ask your physio before you try it if you have had surgery on a wrist or shoulder, have dislocated a shoulder, or have a wrist or shoulder that often hurts.

If you have had a hip replacement, get the go-ahead from your surgeon or physio before you try the ball plank knee tuck. Drawing a knee in under your body, and kneeling down to get on and off the ball, bend the hip to a right angle or past it, and many surgeons ask you to avoid that for the first months after some operations.

Your stomach wall does much of the work of keeping you level. If you are pregnant, check with your midwife or physio before you start. If you have recently given birth, including by cesarean section, or you have a gap down the middle of your stomach muscles (diastasis recti), ask your physio, midwife or doctor first. With a hernia, or after surgery on your abdomen, get your doctor's or physio's advice before you plank on a ball.

If you have high blood pressure, breathe steadily through every repetition and never hold your breath. With a heart condition or high blood pressure, check with your doctor before you start. If chest pain, pressure or tightness does not ease quickly when you rest, spreads to your arm, neck, jaw, stomach or back, or comes with sweating, feeling sick, feeling light-headed or being short of breath, call emergency services straight away, as this can be a heart attack. If it eases quickly and none of these happen, get medical advice the same day, and do not exercise again until you have been checked. If you faint while exercising, call emergency services, even if you feel fine again quickly.

Written and checked by the PocketPhysio editorial team. Last updated 2026-09-28.

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.

Ball plank knee tuck