m.youtube.com/watch?v=EwFZBG_ts4k
A dude called Noel Plum looks through various published studies (and concludes that best way to proceed is to have an ‘open’ category and a protected category for biological females only).
Noel is looking at the topic from the perspective of a well-informed sports enthusiast (as opposed to a feminist one) so he uses cross sex pronouns and the word ‘cis’ but it’s worth powering through for his no nonsense take on what the studies actually say, what their shortcomings are, and how it all relates to the concept of fairness in sports overall.
(A quick glance at his channel shows that he usually makes atheist & anti SJW type content, and has made this video in response to the Rationality Rules v Essence of thought disagreements on the topic, a recent dispute within the atheist community - someone else posted a thread on that a few weeks ago, I will look for it and add to the thread)