If trans athletes can compete in female events, then women’s sport is finished, writes Olympic gold medalist DALEY THOMPSON

During my participation in the decathlon – where I won the gold medal at the 1980 and 1984 Olympics – I saw performances from some inspiring women.

But the truth is that no matter how hard they trained, they could never have matched my times (except for the 1500 meter run, where some women were able to beat me).

My body type was too different – ​​too masculine. It would have been very unfair for me to compete against them. My victory would have been a mockery.

So when I see trans women like American swimmer Lia Thomas or Canadian cyclist Veronica Ivy (formerly known as Rachel McKinnon) on stage, I know they are biologically male and that physical advantage helped them win.

All my sporting instincts rebel against it. If sport is to mean anything, it must be fair.

That's why we need clarity – like that offered by Boris Johnson, who said: 'I don't think biological males should compete in female sporting events. Maybe that's controversial to say, but it just seems sensible to me.

'I also happen to think that women should have spaces – whether in hospitals, prisons or locker rooms – that are specifically for women.'

I am also strongly against trans women being allowed to participate in women's sports. I don't consider this controversial, nor political. It's about honesty.

Trans athletes say they do everything they can to compete fairly, for example by taking testosterone blockers.

Let's put aside the fact that I have strong reservations about the use of hormone altering drugs in sports.

But it seems abundantly clear that no pill can take away the benefits that come from growing up biologically male in terms of muscular and skeletal strength.

These trans women have gone through male puberty. They have longer limbs, broader shoulders, thicker bones, a better power-to-weight ratio and larger heart and blood volumes.

Nothing they can do will change that: they will always outperform biological women.

This is an issue that I've seen grow from a minor issue to a national controversy in sports – and beyond – although in recent months it feels like something is indeed changing.

My belief is that the sport should have a women's division and a new, open class in which transgender women are welcome and can compete fairly.

There must be room for trans women in sports – but not at the expense of all women.

Like any decent human being, I fully support everyone's right to present themselves as they wish, to use the name and pronouns they believe reflect their true selves, and to live their lives as they choose.

It's sad that equal rights for transgender people have been suppressed for so long.

Over the past twenty years we have seen the rise of a more compassionate society – but unfairness towards women is the unintended consequence.

And stripping away outdated gender stereotypes should not allow biologically male predators – who identify as women – to potentially gain access to women's prisons or women's refuges from domestic violence.

Women have fought hard to achieve their safe space. They must be respected.

I've become increasingly outspoken about this on social media and people who visit my gym in Putney, South West London have started asking me about it.

How can a young girl feel inspired to take up sports when she knows she will have to compete with – and lose to – biological males?

And how can a parent feel that his daughter is safe in a locker room where biologically intact male athletes dress and shower next to each other?

Sir Keir Starmer, leader of the Labor Party, could not say what a woman actually is.

It's not hard – if you're in doubt, ask any five-year-old.

I am not interested in party politics. However, I am not surprised that Labour, the Lib Dems and the Greens are being questioned by voters when they do not have the courage to put forward simple biological facts.

Some of my close friends, including Czech-American tennis star Martina Navratilova and record-breaking British competitive swimmer Sharron Davies, have done so and have suffered shocking abuse from trans extremists as a result.

I want the whole world to know that I am standing with them.

I am also shocked by the violent threats against writer JK Rowling, who has spoken only calm common sense.

Does that make me a feminist? Well, no one has ever called me that, but there's a first time for everything.

What I do know is that I am not transphobic or misogynist – two insults that have been thrown at me on Twitter.

When we become afraid to tell the truth, we are really in trouble.

And if trans women are allowed to compete in women's categories, then women's sports are not only in trouble, they're over.