This is really just a rant! and before i begin, I'm referring to a high to low cable wood chop, specifically when performed with spinal flexion and rotation. There are, unfortunately, many demonstrations of this on you tube.
Firstly, loading spinal flexion and rotation places the spine under a tremendous destructive load, it's a crunch with rotation, its not functional or beneficial simply because it loads the abdominal muscles and uses some fancy cable equipment.
Secondly, the constant load produced by the apparatus, requires an isotonic contraction from the musculature involved. This again is non-functional, the kinetic chain would never have to operate in this way, especially not, and ironically, when chopping wood with an axe or whilst brandishing a sledge hammer! During these movements force is initially generated by a combination of flexion and rotation combined with gravity, however, once accelerated there follows a period of relaxation as momentum takes over. On impact, stiffness and therefore further contraction will occur, this, if optimum and safe force is to be generated will take place in a position of neutral braced spine. The movement would then be stopped by the impact or the follow through decelerated by the extensor chain and counter rotational musculature. Basically, the real chop is a totally different movement pattern, in terms of loading and sequencing of muscular contraction, than the cable version. Only joint motion is similar.
If the cable is to be put to any use, hip and shoulder alignment should be maintained, utilizing the abdominal muscles in their intended function, as torque convertors, preventing rotation through the trunk and therefore allowing force to be generated through the entire body safely, primarily via the hip and shoulder.
Trainers should consider carefully when and where to use isotonic load, if at all, and certainly consider spinal positioning whilst under load.
Trainees should never use you-tube as a source of exercise advice!!
