Firstly, place your hands on the floor slightly wider than shoulder width with your arms straight and your toes touching the floor behind you (the top of a press-up).
Draw your belly button in and squeeze your bum muscles.
Build up to holding this position for two minutes. It’s a great regression from a press-up that also really works your abs.
After mastering this, maintain the tension you created in the plank and start bending through the elbows as you lower your whole body towards the ground.
Let your upper arms and elbows come out to 45 degrees as you lower.
Stop when your elbows are level with your shoulders (about halfway).
Maintaining the tension, push the ground away and come back to your high plank.

Bodyweight no. 9: Strengthen stability to stay mobile and injury-free for life