Popsugar Fitness Workouts 20-Minute Back, Shoulders, and Triceps Bodyweight Workout This 20-Minute Bodyweight Workout Is All About Your Back, Shoulders, and Triceps! August 30, 2021 by Jenny Sugar View On One Page Photo 5 of 6 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 5 Side Plank Reach Through (Left Side) Start in side elbow plank on your left side with your feet stacked. Raise your right arm in the air. Lower your right arm in front of your chest and reach it underneath your rib cage through the space behind your left arm. Reach your arm back up into the air to complete the rep. Keep going for 40 seconds, followed by a 10-second rest. Previous Next Start Slideshow WorkoutsHome WorkoutsIntermediate WorkoutsArm Workouts20-Minute WorkoutsArm Exercises