Start in a plank position with your arms and legs straight, shoulders above the wrists.
Keeping your upper arms parallel, bend your elbows lowering your chest until your shoulders are in line with your elbows. The elbows should touch your ribcage.
Straighten the arms to complete the rep. Rest your knees on the floor if you need to.
Do as many push-ups as you can in 45 seconds. Take a 15-second rest.