Push-Ups: For Chest and Core Let's move to the upper body. Push-ups strengthen the chest, shoulders, triceps, and core muscles. Lying face-down, place hands a bit wider than your shoulders. Place toes on the floor, creating a smooth line from shoulders to feet. Keeping core muscles engaged, lower and lift your body by bending and straightening your elbows. Too hard? Place knees on the floor instead of toes. To boost the workout, add an exercise ball under the hips, knees, or feet. Perform 10 re
Cable Pull Down: For Upper Back For the last upper body exercise, do the cable pull down, which works the upper back. Using a cable machine, sitting straight with a neutral spine, grasp the bar with arms extended, see left. Slowly pull the bar down past the face and toward the chest. Only go as far as you can without leaning back, and control the weight on the way back up. Perform 10 repetitions.