In this episode, we dive into the intersection of the menstrual cycle and athletic performance—a topic often surrounded by strong opinions but surprisingly limited evidence. Joined by Dr Kelly McNulty, researcher and practitioner, and Sarah Massey, experienced coach, we break down the key phases of the cycle, highlight when ovarian hormone levels rise and fall, and explore the popular theory that certain types of training should align with these hormonal shifts. But does the science actually support that idea?

Together, we take a critical look at the research—what’s known, what’s still unclear, and where the gaps are. More importantly, we focus on practical, athlete-centered approaches: being symptom-led, being "your own scientist", using tracking tools effectively, and how to open the conversation—especially with younger athletes—in a way that empowers and informs.

Whether you're a coach, practitioner, or athlete yourself, this episode offers a grounded and positive perspective on managing training around the menstrual cycle without falling for the hype.

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Links

• One of Kelly's papers that summarizes the literature and shows a trivial impairment during the early follicular phase
• Paper showing that the anabolic response to resistance training is unaffected by menstrual cycle phase
• Kelly's study on symptoms experienced during menstruation and their perceived effects on training and performance
• Researchers raise the bar for studies on the menstrual cycle by calling for measurement, not guesswork
• "No influence of influence of women's menstrual cycle phase on acute strength performance or adaptations to resistance exercise training"
• Another of Kelly's papers, this one summarizing the literature on the effect of oral contraceptives on exercise performance
• Developing a tool for ovarian hormone profile classification
• Kelly's educational resource, Period of the Period

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In this emergency bonus episode, Ross reacts to the bombshell news: Kenya's Ruth Chepng’etich, who stunned the world with her record-breaking marathon in Chicago last year, has been provisionally suspended by the Athletics Integrity Unit after testing positive for a banned diuretic in March. The performance shocked the running community at the time — questions and doubts sparked a parliamentary inquiry in Kenya after a journalist’s pointed question at the press conference. We even released a podcast titled “Too Good To Be True?” analyzing the run.

Now, that skepticism feels vindicated. Ross breaks down why the doubts were justified despite the usual defenses ("she's always been talented", "she worked hard"). He explains what a diuretic does, why this kind of doping bust leaves him cold and underwhelmed, and how it fits a familiar pattern in elite sport. We also explore the shadowy roles of agents and coaches — and ask why it's always the athlete left holding the bag?

Finally, Ross reflects on the cycle of hope, hype, and heartbreak that defines modern sport — from the marathon course to the Tour de France, can we trust what we see? Why should we, when the characters and incentives remain the same? Same script, different stage.

Links

• The AIU statement on Chepng'etich's provisional suspension
• The timeline as posted by Chris Chavez on X
• Our podcast on the performance at the time - we were highly, highly skeptical
• The Discourse thread at the time of that performance - members only
• The Discourse thread that is growing now, out of the announcement last night - members only

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In a packed episode of Spotlight, we kick off with a Discourse Digest that begins on the grass of Wimbledon, where Jannik Sinner and a dominant Iga Świątek took home the titles. Then it’s to the rugby fields of South Africa, where the Springboks—led by the ever-innovative Rassie Erasmus—have once again found a tactical edge. But is it genius strategy or a rule-bending loophole?

In Center Stage (17:10), the Tour de France is in focus. Jonas Vingegaard's muscle has matched Pogacar on short, punchy climbs, but can he hold his own as the race hits the high mountains? We also break down Remco Evenepoel’s pre-race cooling technique - placing hands and forearms in ice water - to explore what the science says about its effectiveness. Plus, we revisit the ongoing issue of concussions in cycling to explain the paradigm shift that is needed to buy space and time for better concussion identification.

In Ross Responds (52:07), we revisit the topic of cramp and sodium loss, answering a listener question about 'salty sweat' with a dive into how our bodies prioritize the regulation of sodium concentration, and why sweat testing is nothing more than a measure of the body's systems working to defend physiological 'normal'. In Listener Lens (1:00:10), Tim is looking to break a barrier over 10km, and our Discourse community zeros in on the key to unlock that performance: pacing. We offer some advice to help him nail it.

And finally (1:06:53), a Zwift racing series has Ross questioning the platform’s 'fairness'. Are the game's efforts to simulate equipment and drafting creating more distortion than accuracy?

Links

• Article on South Africa's innovative midfield maul set up
• Stanford study that finds that palm cooling (with a vacuum device) improves performance in bench press and pull ups. Too good to be true
• Conversely, study showing that palm cooling does not improve interval running performance
• And conversely again, study showing that immersing the hands and forearm in cold water improves sprint performance
• Healy's power numbers from the day, the trigger for our IF discussion
• Cycling's concussion policy
• For Discourse members only, Tim's question about his 10km quest and discussions on improving pacing
• Discourse members talk cramp

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