Check your plank form with your phone

The plank teaches your core to hold your spine still, which carries over to nearly every other exercise. A short plank with good form beats a long one with sagging hips.

What the camera flags

• Hips sagged
• Hips too high

The plank check is newer and has not had as much testing on real movement, so expect more misses. It can only see one angle, so it won't catch everything.

How to set up your phone

Put your phone on the floor, side-on, about 2 metres away. Keep your head to toes in view.

What to watch for yourself

Hip height

Your body stays straight from head to heels. Level hips keep the work on your core and away from your lower back.

Common mistake: Letting your hips sink, or lifting them up to rest. Try this: Squeeze your glutes and pull your belly button in gently.

Shoulder stack

Your elbows sit under your shoulders. Stacked joints support your weight with far less strain on your shoulders.

Common mistake: Placing your elbows too far forward or sinking between your shoulder blades. Try this: Push the floor away with your forearms and keep your upper back wide.

Breathing

Keep breathing through the hold. Breathing while braced trains your core the way real movement needs it.

Common mistake: Holding your breath until you have to stop. Try this: Take slow, steady breaths without letting your stomach relax.

Muscles worked

Abs, Obliques, Shoulders, Glutes, Lower back, Quads.

A good starting point is 3 × 20–45 sec, with 45–60 sec of rest.

See the full plank guide.

General guidance, not medical advice. Stop if anything hurts. The camera can miss things, so no issue seen doesn't mean perfect form.