I previously wrote about the prevention of injuries in young fast bowlers and the "RED ZONE".  The age group between 16-22 and preventing stress fractures between those ages. Shane Watson, talks about his injuries and highlights major stress fractures at a young age.  He is still plagued by injuries to this day and I believe this is due to 3 stress fractures before the age of 19 and within the "RED ZONE".  A zone, when young fast bowlers can develop stress fractures primarily due to anatomical weakness and secondary due to a mixed action and high workload.  Degeneration to his lower back, has caused him to have multiple injuries along his "neural chain" (nerve pathway) that is, hamstrings and persistent calf injuries.