I am currently doing the Osteostrong 2 week trial. I know the information that weight bearing excercises help grow bone and I tried personal training for a year, which was very difficult and hard to maintain but good for my muscles and general health. I stopped as it was too expensive and time consumimg. I am now trying the Osteostrong machine program which they say target specifically the bone. It does take muscle strength though to put the force onto the machine, but I find it actually much easier than personal training, so I find it hard to fathom how this is better than personal training , and it is troubling me, like another commenter, wondering whether I will ever reach the target force they require for triggering bone growth, with the simple 15 minutes a week of this same machine excercise which definitely cannot increase much muscle growth like personal training did to help me have more force on the machines. The trainer there says my bone strength improves and that is where the strength will come from. Its alot of money so I am very skeptical of this, without more proof that it works, and I can't find the proof because I read that their studies they refer you to are really not supported anywhere else when I research on the internet, besides saying their samples are too small or other deficiencies.