24. Trans Athletes: No Opinions, Just Science!

It’s Olympics time again and for 16 days, the world will celebrate the best in sport whilst weeping for the plucky losers.

A few of the more than 11,000 competitors will be transgender athletes but even that small number will generate a lot of conversation as everyone seems to have a view on the inclusion of trans athletes in competition.

But how many of these opinions are grounded in science?

In fact, how many answers can science offer currently and how many questions still need to be explored?

Join our duo to hear their them give a taste of the scientific knowledge to date and then let them know what you think!

Episode REsources:

Rare or surprisingly common to have a sex chromosome disorder, here are the numbers, you decide!

Use these links to check out where you stack up, height-wise, compared with males and females across the world.

Bone density in trans females appears to stay at the higher biological male levels seen pre-transition.

Adult males typically have larger hearts than adult females but only because, typically, they’re larger!

What’s the most important factor causing biological males to have more hemoglobin than biological females? It’s that lovely testosterone!

You might be surprised to know that scientists don’t fully understand why biological males typically have more muscle mass than biological females – testosterone is one part of the answer but doesn’t explain everything.

Biological males typically have more type 2 fibers, advantageous for explosive, strength-based events than their biological females counterparts who instead have more type 1, fatigue resistant fibers throughout their muscles.

Elite endurance runners and cyclists appear to naturally have a lot of type 1 fibers whereas power athletes appear to have a much higher proportion of the various type 2 fibers.

All of the above matters because switching of muscle fibers appears to be very limited - what you were born with seems to be pretty much what you’ll have throughout your life!

If you’ve already listened to the episode, you’ll know that the USA airforce carried out a fascinating study on 46 trans female recruits, click here to check out that work.

For a ton of interesting research and to see why World rugby currently says no to trans female players in the women’s game, check out their thoughts here.

And see here why USA rugby decided upon the opposite approach.