Alright, everybody, the Glute-Ham Developer (GHD) that Keith ordered for us has arrived and it is assembled, so get ready for a whole new level in your core development.
“The GHD sit-up was once a gym staple. In the gym today only rarely will someone be found doing other than back extensions on the GHD. In no small measure the decline of the GHD or roman chair sit-up coincided with the advent of the crunch. The crunch came to fashion on warnings and claims in popular media of the traditional sit-up‚Äôs destructive impact on the back. It was argued that the GHD style sit-up‚Äôs primary movers were the hip flexors and not the abs and consequently this sit-up, and sit-ups like it, were actually not good abdominal exercises. It was further argued that recruiting the hip flexors to lift the torso was destructive to the lumbar spine. Once every couple of years we get lucky and find an exercise physiologist to repeat this message of poor ab recruitment and lower back destruction standing in front of the GHD apparatus. What we do is ask them to mount the GHD and perform a set of thirty sit-ups for us while rehashing the poor recruitment claim. The fun comes the following day when the report comes back from the exercise scientist that they are almost too sore to sit upright. Laughing, walking, standing, and moving are all excruciating. Where are they hit? The abs.
Our favorite story along these same lines comes from Matt Weaver (www.speed101.com), arguably the world‚Äôs fastest human being. On top of being known for hitting 85 mph on a bike, Matt was crowned ‚ÄúKing Sit-Up‚Äù in high school for completing 100 perfect-form bodyslapping sit-ups (BSSU‚Äôs) in one minute. In one of his earlier visits to CrossFit Santa Cruz he found himself in a multi-station circuit with a group of CrossFit veterans that included twenty-one reps of GHD sit-ups with a full range of motion, hands reaching back to the floor. The workout left Matt sick in the immediate aftermath. This was a surprisefor sure but nothing prepared Matt for what came the following morning: ‚ÄúI awoke later without the slightest ability to sit up. It was as if the six pack was totally gone, though all ribs remained. The curse had left me merely able to roll over and slither like a snake off the edge of the bed. From there I had to use my arms in humiliating ways to move about. I avoided being seen. A week passed, and I began to revitalize.‚Äù
The worst was yet to come! In the wake of Matt‚Äôs being dethroned as King Sit-Up, his abs had swollen and distended markedly. This kid looked fat and sunburned where the week before he‚Äôd been ripped and lily white. As the swelling subsided, his scrotum grew and grew and grew. Matt‚Äôs father, John, is an ER doc, so he was consulted. He laughed himself to near seizure. Our kind of doc. Before the swelling stopped Matt‚Äôs scrotum had become the size of a small and very ugly cantaloupe. Why we have no pictures we‚Äôll never understand. Apparently the fluids that had swollen Matt‚Äôs abs had drained into the inguinal canal and filled the scrotum. Oh, and apparently GHD sit-ups recruit the abs. Matt is convinced.
The lesson we‚Äôve drawn from the GHD sit-up is that in spite of the primacy of hip flexors over trunk flexors, or the abs, in this sit-up it recruits the abs powerfully in two ways. First, the movement takes the trunk from hyperextension to full flexion, albeit with negligible load. (No crunch can match this range of motion.) Second, the role of the abs in this sit-up is powerful and largely isometric – i.e., they stabilize the torso from undue extension. This second point is consistent with our belief that the most powerful, functional, and developmental contractions of the trunk are isometric, not isokinetic. Our favorite ab exercises are predominantly stabilization or isometric exercises. The GHD sit-up, the L sit, and the overhead squat share this stabilization role. The lack of trunk flexion in these moves hides their potency from the uninitiated.” – Greg Glassman