I have recently read four books on bone density. I have learned a lot and I am sure I will eventually share a few facts. The books I have read are mentioned at the end of this post. For right now though, I want to address the issue of weight. I am not referring to body weight, but the amount of weight we lift for a workout for our bones. According to what I have read, any weight lifted 15X is not going to work for bone health. There will be benefits otherwise, but not for bone strength. Almost all authors concurred that the weight needs to feel heavy in shorter sets of 8 and sometimes less. It needs to be hard and always with good form. At the same time, it takes months to get to the point where you can lift with "heavy" in mind. Don't set out to build Rome in a day and end up with enough aches and pains to set you back.
Resources: ACSM Action Plan for Osteoporosis Kerri Winters-Stone, PhD
The BEST Exercise Program for Osteoporosis Prevention Timothy Lohman, PHD/
Scott Going, PhD Lauve Metcalfe, MS / Terri Antoniotti-Guido, PT / Vanessa A. Stanford, MS,RD
Linda Houtkooper, PhD
Your Bones Lara Pizzorno, MA, LMT
The Osteoporosis Handbook Sydney Lou Bonnick, M.D.,F.A.C.P.