As of right now I have 51,*** miles on it and they do feel quite stiffer than when I bought her. Might need to rebuild them soon. I don't offroad it as much I'd like to but, when I do it gets driven hard.
I'd place a small wager your shocks are blown or partially blown. 50K miles seems to be the time when most people are seeing the need to rebuild their shocks if they offroad at all. My truck has 44K miles and I'm pretty sure the shocks have been blown since after Raptoberfest in September. Maybe even before that to be honest.