http://www.sportnetdoc.com/shoulder/inflammation-of-the-biceps-tendon

In case of repeated (over) loading (swimming, throwing) the long
head of the biceps muscle (caput longum biceps bracii) becomes inflamed. With
age and repeated loads the biceps muscle becomes marked by wear and tear, which
increases the chance of ruptures.

Slowly insetting localises tenderness exterior and to the front of the shoulder
after load. Sometimes radiating down the upper arm.

Rehab:

http://www.sportnetdoc.com/inflammation-of-the-biceps-tendon/step1

http://www.sportnetdoc.com/inflammation-of-the-biceps-tendon/step2

and so on.