You most likely did a push-up at some stage in your life before beginning CrossFit, but you may not have done the full spectrum of motion pushups we use in CrossFit. Your arms should be absolutely straight at the top, and your chest should be in touch with the ground at the bottom.
400 meter Ruck Run (35/25 lb) 101 second Ruck Squat Hold (35/25 lb) 400 meter Ruck Run (35/25 lb) 50 Ruck Push-Ups (35/25 lb) 400 meter Ruck Run (35/25 lb) 101 second Plank Hold with Ruck (35/25 lb) 400 meter Ruck Run (35/25 lb) 101 Burpees 400 meter Ruck Run (35/25 lb) 101 second Overhead Ruck Hold (35/25 lb) 400 meter Ruck Run (35/25 lb) 100 meter Bear Crawl Ruck (35/25 lb) 400 meter Ruck Run (35/25 lb) 50 Ruck Thrusters (35/25 lb) 400 meter Ruck Run (35/25 lb)