And asking for research proving a relationship between muscle injury/ skeletal injury and fatigue?
There is tons of it. Start at the "International Journal of Fatigue", try reading their article titled "The nature of fatigue damage in bone" by Clive, O'Brien and Taylor.
There is lots of research. If you are unable to access university data base systems for the latest and most up to date journal information try using google scholar, even your newspaper will have information. Enjoy the reading, and best get a cup of tea or a cold beer to sip while you read, as you will be there for quite a while. Even the workcover Victoria website has info on fatigue and muscle injury - muscular skeletal or however its meant to be spelt!
