Dr. Stacy Sims

So then when we see this discrepancy of being sporty, not sporty, we see the changes in body composition. And all of this is in those early stages of the teen years, which is another knock because we also have brain changes where girls become more self-aware and boys don't. They're like, okay, you know what? You piss me off. I'm going to beat you up and we're going to get on with it.

But girls are very self-aware and they hold on. things to themselves in a more negative fashion. And this creates a lot of mood changes. And this also creates a feeling of negative body positivity. So they don't feel that comfortable with how they look or who they are. And society doesn't help that either.

But girls are very self-aware and they hold on. things to themselves in a more negative fashion. And this creates a lot of mood changes. And this also creates a feeling of negative body positivity. So they don't feel that comfortable with how they look or who they are. And society doesn't help that either.

So this all perpetuates in a sociocultural as well as a biological change with regards to exercise.

So this all perpetuates in a sociocultural as well as a biological change with regards to exercise.

Yeah. So if we see essential fat for men is around 4% to 8%, so that means what we need for our nerves and just survival. For women, essential fat is around 12%. So this is for nerves and looking around our essential organs to survive.

Yeah. So if we see essential fat for men is around 4% to 8%, so that means what we need for our nerves and just survival. For women, essential fat is around 12%. So this is for nerves and looking around our essential organs to survive.

We look at body composition itself, we see that women tend to sit around 20% as a normal healthy individual, although the data's changed over the years, and men sit around 15%.

We look at body composition itself, we see that women tend to sit around 20% as a normal healthy individual, although the data's changed over the years, and men sit around 15%.

So women have smaller heart and lungs relative body size to men. We also have less hemoglobin. So that means our oxygen carrying capacity is lower. Because if we are looking at our red cells and we have four different what we call heme molecules in a red cell and each one carries oxygen. Our red cell count is lower as compared to men because the red cell count is driven by testosterone.

So women have smaller heart and lungs relative body size to men. We also have less hemoglobin. So that means our oxygen carrying capacity is lower. Because if we are looking at our red cells and we have four different what we call heme molecules in a red cell and each one carries oxygen. Our red cell count is lower as compared to men because the red cell count is driven by testosterone.

So men have around 100% more aromatized testosterone as compared to women. So this increases the carrying capacity of oxygen, which means it goes to the muscles, can deliver more fuel to the muscles to be able to contract better. have more power and more strength.

So men have around 100% more aromatized testosterone as compared to women. So this increases the carrying capacity of oxygen, which means it goes to the muscles, can deliver more fuel to the muscles to be able to contract better. have more power and more strength.

Not that they breathe more. When we're talking about oxygen carrying capacity, this is... The amount that you're taking into the lungs, how it transfers to the red cells to then be able to go to the working muscles to give the muscles the available fuel to do a contraction. So it's not a respiratory rate. It's the ability for you to breathe in and how fast that can be conducted to the muscle.

Not that they breathe more. When we're talking about oxygen carrying capacity, this is... The amount that you're taking into the lungs, how it transfers to the red cells to then be able to go to the working muscles to give the muscles the available fuel to do a contraction. So it's not a respiratory rate. It's the ability for you to breathe in and how fast that can be conducted to the muscle.

It's more of a power and speed factor. Okay.

It's more of a power and speed factor. Okay.

Yep.

Yep.

So when we're looking at, I guess, world records, right, that have been kept, and we see there's a gender gap there. And this is slowly closing in the endurance world, but that has to do with muscle morphology with regards to being able to go long and slow.