Workout of the Day
Take approximately 10-12 minutes to work up to approximately 85% of your 1-RM deadlift;
Every four minutes, for a total of six sets, complete the following as quickly as possible:
Deadlift x 3 reps (use approximately 85% of your 1-RM)
Box Jumps x 12 reps
Sprint 200 Meters
Recent events have led me to brush up my knowledge on shoulder anatomy and function. The shoulder is a common site for injuries among athletes, and for those who pursue the sport of CrossFit – with its high volume pull-ups, emphasis on Olympic Lifts, and a fair amount of pressing overhead – it’s critical to have an understanding of the structure and potential issues related to this incredibly mobile and potentially vulnerable joint. My goal is to provide a baseline level of education on the components that make up the shoulder (the bones, tendons, ligaments, and muscles), some common maladies associated with the shoulder, and preventive measures that everyone can employ.
The first thing to review in the shoulder girdle is the osseous anatomy – the bones. Sometimes referred to as the pectoral girdle, the shoulder is comprised of three bones:
Humerus – the upper arm bone
Scapula – the shoulder blade
Clavicle – the uhh…clavicle
The articulations that give the shoulder it’s great mobility are:
Acromioclavicular joint – where the acromion and clavicle meet
Sternoclavicular joint – where the sternum and clavicle meet
Glenohumeral joint – where the head of the humerus sits in the glenoid
Scapulothoracic joint – the scapular is suspended on the thoracic wall by muscle forming a “functional joint”
Go ahead and read it again, refer to the picture, and maybe feel up yourself (or a friend). Find your acromion and trace it back to the spine of the scapula. Find your sternoclavicular joint and move your shoulder around. Now see what kind of range of motion you have if that sternoclavicular joint doesn’t move. Now stop what you’re doing and make sure your officemates aren’t laughing at you.
Earlier I said that the shoulder was potentially vulnerable. The shoulder is an incredibly mobile joint capable of achieving over 16,000 positions, which can be differentiated by 1° (just think about how many directions you can point your finger). In order to achieve this kind of mobility, the shoulder has to sacrifice significant stability. Look at the humeral head and where it sits in the glenoid cavitiy; only about 30% of the humeral head contacts the glenoid – not the model of stability. What holds the ball in the socket is a complex system of ligaments, tendons, and muscles. A system that we will continue reviewing tomorrow….