Just the bare bones this week as we find out how exercise strengthens the skeleton and how new scanning techniques can help to pick up osteoporosis earlier and inform its management. We also try out a new gadget for measuring the force muscles can apply and, in the news, discover what a self-healing tumour can tell us about common cancers, evidence that mammalian hearts can repair themselves and a new laser-based tool for diagnosing melanoma. Plus, how the bones of people who died up to a hundred years ago are helping scientists to combat chronic back pain by building a computer model of the backbone...