A client sent me a good article today, http://nyti.ms/1ceYdAi, on high-impact exercise on bone mass. The researchers said they need more research to discover exactly how much force is required to maintain or build bone. They did recommend folks to run, jump, hop some. Since I'm not sure too many people will be able to or want to run, jump, hop, I added this link https://www.precisionnutrition.com/all-about-bone-health, which addresses bone health from the nutrition angle. If you are interested in running, jumping, hopping, and you're not sure what to do, give me a shout and I'll help you. This is all very depedent on the individual. Happy reading!