Training Board is…

Training Board is basically my gym notebook.

In theory, I can also blog in a more public spirited way about weightlifting, nutrition, weight loss, etc. But mostly, I just use this blog to track my workouts. And surfing.

If anything I have posted seems useful to you, let me know with a comment.

About Me

I'm a level I "sports performance certified" USAW coach, and I train, and work as a trainer at Asheville Strength and Conditioning, a great little gym here in Asheville, N.C.

I work with clients who want to get strong and fit, and am especially happy with helping older or detrained individuals.

My own training now is more focused on developing strength and using basic lifts and classic strength and conditioning techniques. A lot of the older portions of this blog deal with CrossFit and reflect my journey into fitness self-awareness. I first discovered CrossFit, back in late 2008. I learned a lot from CrossFit's "fitness as sport" model of training -- and benefited tremendously from training with my friends at CrossFit Asheville -- and furthermore I must credit my interest in CrossFit for opening my eyes to the larger world of training for strength athletics, Olympic-style weightlifting, powerlifting, and other arcane approaches to moving the Iron around.

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Reflections • August 12, 2011, at 9:18 pm

Concerning the anatomy of the Radius and Ulna


Skeletal anatomy of the arm (pictured: right arm, with supinated hand).

Skeletal anatomy of the right hand.

Schematic (overly simplified) drawing of skeletal anatomy of the forearms.

So, because of breaking my left radius two weeks ago, I’ve been trying to educate myself about the treatment, healing, and rehabilitation of this particular injury. To my taste, no better source of information exists than the online Orthopedics textbook at Duke University, Wheeless’ Online. What I read there about the forearm and its osteoanatomy got me thinking about how the radius and the ulna function in various weightlifting, bodybuilding and powerlifting activities.

The radius is the bone that runs from the base of the palm beneath the thumb to the outside (lateral side) of the elbow. The ulna is the bone that runs from the base of the palm beneath the pinky to the inside of the elbow.

In neutral (hand shaking) position, the joints connecting the radius and ulna to the hand (on the distal ends) and the elbow (on the proximal ends) are turned 90 degrees (roughly) to one another causing the radius and ulna to form a triangle with the elbow, with the point at the hand (distal) end.

When the hands are supinated (palms towards the face) the radius and ulna are more or less parallel.

When the hands are pronated (palms away from the face) while the arm is bent, the radius and the ulna are crossed (nearer to the distal end).

When the hands are pronated and the arm is extended, the humerus rotates, and the radius and ulna make a triangle with the point at the elbow and the base at the hand.

The two lines never actually touch; the two pairs of joints at either end of the radius and ulna — either the medial and lateral epicondyles on the proximal head of the humerus or the scaphoid/radius luna/ulna joints of the carpal bones of the wrist — rotate independently and keep the bones apart.

All positions of the radius and ulna provide a truss-like structure to transfer power from the elbow to the wrist. The supinated grip, with its parallel bones forming a sort of rectangular plane, provides the most direct, lever-like use of the contracting force of the bicep. The neutral and pronated grips all form a type of tetrahedron, as the joints at either end of the two bones rotate around each other. These tetrahedral shapes are very strong trusses that can support enormous weights when locked out properly to the wrists and humerus.

I haven’t taken these thoughts much further, but they could influence various decisions about how to train athletes; for example, considering which exercises stimulate which joints, and the manner of stimulation, you could design substitutions for lifters suffering from various injuries or conditions (e.g. medial epicondylitis, aka ‘golfer’s elbow’; or lateral epicondylitis, aka ‘tennis elbow’; or a sprain or injury to either carpal joint).

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hi mom!