McGill Curl-Up
A small lift of the head and shoulders from the floor with one knee bent and the hands under the lower back. It trains the abs to brace while the lower back stays in its natural curve. Choose it as back-friendly ab work or with the bird dog and side plank.
Updated
Primary muscles: Abs. Supporting muscles: Obliques, Core. Equipment: Bodyweight.
Muscles worked
Equipment

How to do it
- Lie on your back with one knee bent and the other leg straight on the floor.
- Slide both hands palms down under the lower back to keep its natural curve.
- Brace the core before you move.
- Lift the head and shoulders a few centimetres off the floor as one unit.
- Hold the top for 8 to 10 seconds with the neck still.
- Lower under control and switch the bent leg halfway through the set.
Watch for
- Tucking the chin to the chest.
- Flattening the lower back into the hands.
- Curling up high like a sit-up.
Breathing
Breathe normally through the hold without losing the brace.
Tip
Lift the elbows slightly off the floor once the basic hold feels easy.
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