Slobbin' around lead to a strain? Something that will actually heal, instead of having to be 'managed long term'? At your age, you got away clean, dude! BTW, I got a rowing machine and it toned up the lower back real well. It's also good for arms & abs. The bike does the legs & cardio, the machine does the top end. It's nice to have it on rainy days, too. bk