Lie on your back on the floor. Rest your head relaxed on the floor and look upwards. Stretch your arms straight up so that your hands are roughly level with your shoulders. Lift your legs and bend your hips and knees to approximately 90 degrees. Your thighs should be pointing upwards, whilst your lower legs are roughly parallel to the floor. Keep your pelvis in a stable position and consciously engage your abdominal muscles. Your lower back should remain stable throughout the exercise and should not progressively arch into a hollow back during the stretching movement. Extend one arm and the opposite leg simultaneously and in a controlled manner, in line with the body. Slowly bring the arm behind the head and the opposite leg forwards or downwards at the same time. Lower the arm and leg towards the floor only as far as the position of the pelvis and lower back can be maintained in a controlled manner. Hold the stretched position briefly. Then slowly return the arm and leg to the starting position. For the next repetition, use the opposite arm and leg. Alternate sides evenly. Continue to breathe calmly throughout the entire movement and maintain core tension.
Attention:
The lower back gradually lifts off the floor, resulting in a pronounced hollow back; abdominal tension is lost during the extension movement; the arm and leg are lowered further than the stability of the torso allows; the pelvis tilts or rotates noticeably to one side; the movement is performed too quickly or with momentum; the arm or leg is placed completely flat on the floor, thereby losing active tension; the head and shoulders are unnecessarily tensed or lifted off the floor; breathing is held during the exertion; maintain stable control of the lumbar spine throughout the entire movement; the key is not to lower your arm and leg as far as possible, but to perform the movement only within a controllable range of motion.
Lighten:
Lower your arm and leg less far towards the floor; keep the moving leg more bent, thereby shortening the lever; move only your legs alternately and keep your arms in the starting position; move only your arms alternately and keep your legs stable in the starting position; pause briefly between each repetition and re-engage your core; initially move only one limb at a time.
Harden:
Lower your arms and legs closer to the floor to increase the range of motion; fully extend your leg to increase the lever arm; Use weighted cuffs on your arms or legs; deliberately slow the lowering movement to 3–4 seconds; hold the extended position for 2–3 seconds; perform repetitions alternately without a break in between, whilst maintaining constant core tension.
