Well, the normally turnover rate for tendons/ligaments is approx 300-500 days so if your only cycling for lets say 24 weeks a year or so it will likely not be anything to worry about. Only those that are on higher doses for most of the year should have something to worrry about. Even then, look at the number of pro's who lift insane amounts of weight, how often do they sustain terrible injuries? Sure it happens but I would think if the effects were as bad as animal mass states (ie 50-80% reduction) then I would think those guys would be suffering severe injuries much more often than they do.