Muscles worked
Core, lower back, glutes, shoulders.
Why bird-dog works
Extending an opposite arm and leg creates a rotational force that your core has to resist to keep your hips and shoulders square — this "anti-rotation" demand is why physiotherapists commonly prescribe it for rehabbing and preventing lower-back issues, rather than exercises that move the spine.
How to do bird-dog
- Start on all fours, hands under shoulders and knees under hips.
- Brace your core to keep your back flat.
- Extend your opposite arm and leg until they are level with your body.
- Hold briefly, keeping your hips square to the floor.
- Return and switch sides.
Form tips
- Reach long rather than high.
- Keep your hips level — do not rotate.
- Move slowly and with control.
Common mistakes
- Arching or rotating the back.
- Lifting the leg too high.
- Rushing the reps.
Who should modify or avoid this
Generally one of the safest core exercises, well suited to those returning from a back injury under professional guidance. If you struggle to keep your hips level, reduce the range (a shorter reach) rather than pushing through visible rotation.
Sets and reps
3 sets of 8–12 reps per side.
Variations & progressions
- Easier: extend just an arm or just a leg.
- Harder: add a pause or a small crunch (elbow to knee).
- Try it from a plank for more challenge.
Looking for a full routine? Try our beginner bodyweight workout.