[St Charles Owl]

I was just thinking about the comparisons with fast bowlers in cricket.  They can bowl for three days in a row with the huge strain upon there bodies and they seem to withstand the pressure/strain most of the time.

Yes, but the bowling motion of a cricketer is much less damaging on the arm than a pitcher in baseball.  Cricketers do not throw the ball, their motion is like a windmill with the arm more or less straight.  A pitcher in baseball throws the ball and the torque put on the shoulder and particularly the elbow is a lot greater.  I think most pitchers would tell you that their muscles could cope with throwing far more often than they do but their joints would be destroyed.