Because I feel like the assumption, I guess, and where I'm getting at is that, is the bone mineral density what determines how much load the bone can take, or is there other properties of the bone? I see.

Yeah, there absolutely is other properties.

So bone strength is influenced by its material properties.

So for example, bone mineral is kind of this beautiful composite of like a collagen-like matrix and then minerals.

And so the minerals are embedded in this matrix.

And so it gives it both this toughness and ability to resist tensile forces, but like tension, like pulling, right? but also good compressive strength.

So it's a really nice composite material.

In terms of load, and I know that we've kind of spoken to this already, but here on resistance training, whether it's the landmine press or it's the squat, how do we think about load? Whether someone's body weight is enough, if they should be adding weight, how does that person kind of troubleshoot that at the individual level?

We know about exercise and let's just, let's start with bone loss before bone, gaining bone, but let's talk about the exercises that help prevent bone loss.

Yeah.

So one of the caveats about that, that area of research is that we don't have the, the clinical trials aren't as strong as they are in the fall prevention space.

So we do have clinical trials that have looked at the effects of exercise on bone density.

But they're not as high, like overall the body of research is not as high quality or high certainty, I guess, like in terms of how confident I feel about making conclusions.

They're not as high certainty.

So a lot of the studies have been quite small.

Let's talk about your thoughts on weighted vests.

But maybe, maybe just maybe, Dr. G, am I wrong? Is there a robust amount of literature on, you know, load, absolute load versus relative load specific adaptations to resistance training in highly trained individuals that I don't know about?

So that's a tricky question to answer.

So I would say most of the work that I've done in the kind of my wheelhouse is the work that's been done in sort of 50 plus and often in people with low bone mass.

But not always like so either the 50 plus heterogeneous for bone mineral density or people with low bone mass.

And I will say that in people with low bone mass, there's definitely not enough data to make any conclusions about, you know, this intensity is more effective than this intensity.

If we look at people who are more, and often the studies in the 50 plus are done in postmenopausal women, because, you know, when you do clinical trials, you often target the people who are at highest risk.

So a lot of the trials have targeted postmenopausal women.

So when we look at these trials that have an impact training component, how is that usually programmed? What does that really look like? And how would somebody who's listening go about actually doing that in a way that I guess I would say is maybe safe or has like an acceptable risk profile where they can actually ease their way into it.

But maybe, maybe just maybe, Dr. G, am I wrong? Is there a robust amount of literature on, you know, load, absolute load versus relative load specific adaptations to resistance training in highly trained individuals that I don't know about?

So that's a tricky question to answer.

So I would say most of the work that I've done in the kind of my wheelhouse is the work that's been done in sort of 50 plus and often in people with low bone mass.

But not always like so either the 50 plus heterogeneous for bone mineral density or people with low bone mass.

And I will say that in people with low bone mass, there's definitely not enough data to make any conclusions about, you know, this intensity is more effective than this intensity.

If we look at people who are more, and often the studies in the 50 plus are done in postmenopausal women, because, you know, when you do clinical trials, you often target the people who are at highest risk.

So a lot of the trials have targeted postmenopausal women.

So when we look at these trials that have an impact training component, how is that usually programmed? What does that really look like? And how would somebody who's listening go about actually doing that in a way that I guess I would say is maybe safe or has like an acceptable risk profile where they can actually ease their way into it.

Yes.

Um, and then you layer onto that other things that can cause decreases in bone mass, so exposures to certain medications or health conditions or whatever.

Menopause, so estrogen helps to, uh, prevent bone loss because it inhibits osteoclasts, which are the bones that break, the cells that break down bone.

And so when we ha- when people go through menopause and they start experiencing declines in estrogen, then they tend to have, um, uh, more bone loss.

So in the three to five years surrounding menopause, people can have accelerated bone loss, and then it kind of goes back to the age-related loss, right? And so that bone loss that happens can be a little bit variable.

So some people experience really fast bone loss and a lot of it.

Some people experience less.

Thank you.

If someone's wondering how does resistance training, let's say lifting a weight or body weight resistance training, how is that stimulating the bone differently to some type of impact training?

Yeah, I mean, so Wolff's law, like in simple terms, is, you know, your, your bo- your bones are gonna adapt to the forces that are applied to them.

So, um, you know, if you're applying, um, you know, bending forces, they're gonna get stronger in bending, right? You bring up a good point.

So we think about impact exercise as like if I'm jumping, I'm applying a force to the ground, and there's a, a reactive force applied to my body from the ground, and that's, uh, those ground reaction forces.

When we're doing resistance training, you are, your muscles are attached to bone and they're contracting, and so they're pulling on bone.

So they're, um, generating forces directly applied to the bone.

And so it's thought that both of them potentially could stimulate, uh, uh, bone cells to eventually, uh, increase their activity and, and grow bone.

For someone who has, like, vertebral fracture history or anyone?