Elasticity, stress and strain play a major role in injuring the Ulnar Collateral Ligament. It is a known scientific study that the Ulnar Collateral Ligament can with hold a maximum Valgus stress of 33Nm.  With that being stated the Ulnar Collateral Ligament is exposed to approxiametly 62-65Nm which each and every overhead throw that a pitcher performs.  It is only a matter of so many throws before a pitcher will exert to much force on this ligament.  This can be minimal damage to very severe ligament damage.  Overhead throwing comes along with the risk of spraining, tearing, or complete tear of your Ulnar Collateral Ligament.  Not only can overhead throwing lead to ligament damge and ultimately Tommy John surgery in athletes; it can also lead to Ulnar nerve damge and damage to the surrounding muscles.  These muscles include the Biceps Brachii, Brachialis, Brachioradialis, Triceps Brachii, Aconeus, Supinator, Pronator teres, and Pronator Quadratus.  

Elasticity is the property of solid materials to return to their original shape and size after forces deforming them have been removed. Chronic stress from throwing a baseball overhead will decrease the ability for your ligaments to be able to return to their normal shape and size!