There are no extant written records of the make-up of the broader categories of soldiers and sailors, but since the "Mary Rose" carried some 300 longbows and several thousand arrows there had to be a considerable proportion of longbow archers. Examination of the skeletal remains has found that there was a disproportionate number of men with a condition known as "os acromiale", affecting their shoulder blades. This condition is known among modern elite archery athletes and is caused by placing considerable stress on the arm and shoulder muscles, particularly of the left arm that is used to hold the bow to brace against the pull on the bowstring. Among the men who died on the ship it was likely that some had practised using the longbow since childhood, and served on board as specialist archers.