I can’t remember when I first became aware of the phrase: “Women are not small men.” But once I’d heard it, I started hearing it everywhere. Fitness types on social media kept alluding to it. Friends would talk excitedly about the new strain of female-specific exercise research, which was smashing the template we had all held dear for years. And the originator of the phrase, Dr Stacy Sims , was suddenly on every podcast you cared to name. A highly credentialed sports scientist with a huge social media following, she’s hard to avoid, if your algorithms skew vaguely towards self-optimisation content. While her stance remains divisive in the sports science world, it has the kind of splashy, audacious quality that mainstream exercise advice does not. As a result, it has taken hold in a big way. You might say that Stacy Sims is to women’s exercise what Dr Chris van Tulleken is to ultra-processed foods: changing the conversation almost single-handedly while undaunted by any pushback.…