10 Trainer-Favorite Bodyweight Exercises to Get Stronger, No Dumbbells Required

New York City-based trainer Reggie Chambers, NASM, said that V-ups are one of his favorite exercises for strengthening the core. "It hits the lower and upper abs together, and if done properly, it will increase the heart rate, giving it a cardio effect as well."

• Lie face up with your arms and legs extended and resting on the floor.
• Keep your abs tight, and lift your hands and feet to meet over your torso.
• Lower your arms and legs toward the floor to complete one rep.
• If this variation is too difficult, bend your knees.