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 (pictured). 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; lean forward to hinge at your hips with your knees 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 each hand with your palms facing one another. 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. You and your partner should each pull back on the handles, at the same time. The pulling motion should be initiated from the shoulder blades. Use the muscles of your upper arms (triceps) to straighten your arms directly behind you.
Once your arms are straight, stay strong in the abdomen, shoulders and pelvis to maintain spinal stability. Hold the arms in a straight line and pulling against the resistance.
Together, each partner allows the right arm to bend slowly at the elbow working against the tendency of the tube to shorten. Keep the left arm straight behind you.
Both partners engage the upper arm muscles (triceps), straightening the right arm while simultaneously allowing the left arm to slowly bend. Continue alternating the action of the arms. The right arm should be straight while bending and straightening the left arm and left arm should be straight while bending and straightening the right arm.
Exercise Variation: To increase the intensity of the exercise, stand further away from your partner to create more resistance through the rubber resistance, or increase the speed (velocity) of the movement for enhanced power production and work-rate.
Remember to keep your feet planted into the floor with your abdominals engaged and contracted (braced) to ensure spinal stability.