- long head: infraglenoid tubercle of scapula to olecranon process. functions in joint stability (shunt muscle) - medial head: dorsal surface of humerus to olecranon process.most active of the head in all three positions.- lateral head: dorsal surface of humerus to olecranon process.Strongest, but only active against resistance.unctions in joint stability (shunt muscle) - medial head: dorsal surface of humerus to olecranon process. most active of the head in all three positions. - lateral head: dorsal surface of humerus to olecranon process. Strongest, but only active against resistance.
The ES 500 is a great little backup unit. Easy to use, long battery life (about 25 min. with a desktop PC plugged in; 2 hrs. with a notebook PC plugged into it). It includes full surge protector capabilities, so you won't need to buy another one of those.
The average 2012 laptop battery can hold from three to five hours of charge, although that number can differ depending on what programs are being used on the computer and the computerâs settings.