Popsugar Health & Fitness Workouts Core Activating Exercises You're Making a Mistake If You Don't Do These Ab Exercises Before a Workout — Here's Why 5 March 2019 by Tamara Pridgett View On One Page Photo 8 of 8 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 8 Elbow Plank Start face down on the floor resting on your forearms and knees. Push off the floor, raising up off your knees onto your toes and resting mainly on your elbows. Contract your abdominals to keep yourself up and prevent your booty from sticking up. Keep your back flat — don't let it droop or you'll be defeating the purpose. Picture your body as a long straight board, or plank. Hold for 15 seconds. Repeat two times. Previous Next Start Slideshow Trainer TipsBody WeightFitness TipsBodyweight ExercisesCore ExercisesStrength TrainingWorkoutsAb Exercises