5 Russian Twist
Sets: 3 Reps: 20-25
Grab a medicine ball, dumbbell, or weight plate and sit on the floor with your hips and knees bent 90 degrees. Hold the weight straight out in front of you and keep your back straight (your torso should be about 45 degrees from the floor). Explosively twist your torso as far as you can to the right, then reverse the motion, twisting as far as you can to the left. Do not let your feet come off the floor.