How much weight lifting is required to build bone?

Hi - It would be helpful to know if your research was done in a professional capacity ir if this is anecdotal evidence. You say, "My research shows we need to lift 4.2 times body weight to stimulate bone growth. And we have to hold that weight 40 seconds--more than 78 seconds does no additional good. And we should do this major weight-lifting only once a week because if we do it more often, the bone growth slows..." So for me I would be lifting 600+ pounds and holding it for a minute or more. On other forums, participants have described good results without mentioning such heroic gestures.

I would like to see more information about HRT for ‘seniors’ a decade or 2 beyond menopause as well.

Squats with kettlebells is almost always part of my twice weekly gym sessions. Now doing 24ks - 93 lbs. Started off 6 months ago with 8ks. All under careful supervision of a licensed physiotherapist who does a variant of the ONERO program. Wouldn't dream of doing it with a PT. Anyone can set up shop as a PT. Am so happy with my latest DEXA results am thinking of getting one each six months. Am 76 and on anastrozole.

@freckle1 If by "PT" you mean Physical Therapist then I don't know what you are thinking? The two words have almost the same meaning. In the US trained licensed PT's give non-drug therapy like movement and exercise guidance and physical manipulation. In some other countries like Australia a very similar trained licensed practitioner is called a physiotherapist.
Perhaps "PT" means something else to you?

@freckle1 If by "PT" you mean Physical Therapist then I don't know what you are thinking? The two words have almost the same meaning. In the US trained licensed PT's give non-drug therapy like movement and exercise guidance and physical manipulation. In some other countries like Australia a very similar trained licensed practitioner is called a physiotherapist.
Perhaps "PT" means something else to you?

I started looking into it because I vaguely remember one of the member had mentioned about it as Merodyne being expensive and not everyone can afford. I look at anything from science/physics point of view. Also, I have not seen any US based reviews on Merodyne. They have few older ones from women based in UK on You tube also, not seen any on their website either. If it is so good as couple of the YouTubers say, I would like to know the data and how many women in US have used it and their experience using it. If developed with Nasa for astronauts, do they use it? Why is NASA is not promoting it for the welfare of the general public? To me, proof of the pudding is in eating no matter what it costs. It is for the benefit of my own health.
I am still looking for the right one, where people who have used it and some kind of experience. Meanwhile, if you come across anything please keep us updated. Thanks.