Never too late to start, I am just starting to get back into shape like I have not done for 30 years of letting myself go. I not an expert but us older folks need to just be more careful, probably more important to do proper stretching, & monitor the heart rate and keep under the recommended max. Really pay attention when you body complains, need to learn the diff between good & bad pain, if that makes sense. Also I noted that for me, since I don't run around chasing tennis balls or whatever like I did when younger, side to side related muscles seem to be weaker.