Starting Position: You and a training partner should have specialized resistance x-pattern resistance tubing with four handles so that two people can use it at the same time; or take 2 pieces of standard resistance tubing with handles and cross them to interlink them and create a 4-handled pattern. You and your training partner should stand facing each other with your feet hip-width apart and the right foot slightly in front of the left to create additional stability; your knees and hips should be slightly bent so that you each can sink into your hips and contract your abdominals (bracing) for additional stability. You and your partner should each position your body with the spine in neutral (normal-to-flat), shoulders blades pulling down and back toward the hips (no shrugging). You and your partner should each keep your chest held up and out, with your heads in line with your spine or slightly lifted. Hold the handles firmly in both hands, palms are facing the ground. Pull back slightly to create opposing lines of pull.
You and your partner should each maintain an abdominal contraction with your feet planted on the floor to create stability through the hips and core. Both you and your partner pull back on the handles, at the same time. The pulling motion should be initiated from the shoulder blades. Pull the handles toward your ribcage. Keeping the elbows wide, engage the upper back and shoulder muscles.
Once you and your partner have pulled the handles back, both partners should hold the shoulder blades back and down. Holding this engagement in the shoulder blades, each partner straightens his or her right arm, as though you are "punching" toward your partner. Keep the left arm pulling back.
Pull the right arm back. Hold the contraction once again. Without allowing any movement in the right shoulder, reach the left arm forward. Keep the abdominals braced and alternate the arm movements. You and your partner should work together to provide resistance to one another while simultaneously pulling back on the bands to maintain tension in the band.
Exercise Variation: Start with slow, steady consistent movements to become used to providing manual resistance through the tension of the rubber tubing. To increase the intensity you can either stand further away from one another to create additional tension on the rubber or increase the speed of the movement to make it more of a power-based exercise.
Remember to keep your feet planted into the floor with your abdominals engaged and contracted (braced) to ensure spinal stability.