Great information on safe ways to exercise if you have bone density issues. It really makes sense of the old adage "One size doesn't fit all" and Martin takes this into consideration thruout book. Esp. in the design of a weekly exercise routine for 12 wks catering to each person's bone density rating.
I'm glad i bought it and use it's info when i exercise to correct anything i was doing wrong in the past and to incorporate exercises designed to strengthen spine/bones into my routine.