This is a method for stringing heavier bows that relies on a waist cable and mostly leg strength. In Turkish, the waist cable is known as the "kemend".
Further info on this method here:
* Gokmen Altinkulp: https://youtu.be/BVPs9zRASfU
* Blake Cole: https://youtu.be/48S8EJwrP4c
More info on The Way of Archery: http://thewayofarchery.com