How much do hormonal fluctuations really influence performance and recovery? Should women be adjusting their training and nutrition based on the menstrual cycle? And do female athletes need different protein strategies or recovery protocols than men?

These are questions that have fuelled countless online claims, from rigid "cycle syncing" programmes to supposedly gender-specific nutrition rules. But how much of that is actually grounded in evidence?

In this episode, the conversation tackles those debates head-on, exploring what we truly know about female physiology, adaptation, and recovery, and where confident narratives outpace the science.

You'll hear from four leading experts: Professors Kirsty Elliot-Sale, Stu Phillips, Shona Halson, and Dr. Eric Helms, as they unpack the data on menstrual-cycle variation, autoregulation, and the real determinants of muscle growth and recovery in women.

These discussions were originally recorded live as part of "The Inside Advantage" event hosted by Optimum Nutrition at the McLaren F1 Performance Centre in the UK, where Danny Lennon moderated the session.

• [02:07] Introducing the topics of discussion
• [07:46] Understanding the menstrual cycle
• [09:22] Recovery and hormonal impact
• [10:23] Where did "cycle syncing" claims originate?
• [15:01] Indirect effects of hormones on performance
• [17:28] Sleep and menstrual cycle
• [18:46] Training adaptations and hormonal differences
• [26:29] Do we have research on female athletes?
• [29:20] Muscle building: are there sex differences?
• [34:01] Do hormones influence training?
• [45:08] Key ideas segment (Premium-only)

• Go to episode page (includes study links, guest bios, & more)
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• Watch: Optimum Nutrition's 'Inside Advantage' event
• Previous episodes with these guests: #'s 452, 280, 192, 454

This episode centers on the critical gap in nutrition education within medical training and efforts to bridge it. Guest Akash Patel, a medical student who led a pilot nutrition curriculum, discusses why doctors receive little formal training in nutrition despite poor diet being a major driver of disease. With diet-related conditions (obesity, diabetes, cardiovascular disease, etc.) contributing heavily to morbidity and healthcare costs, the conversation highlights a pivotal push to better equip physicians in nutritional knowledge and counseling.

Patel's work comes at a turning point: there are now calls for standardized nutrition competencies in medical education (e.g., a recent JAMA consensus) and a growing recognition that improving doctors' nutrition literacy could enhance patient care and public trust. But at the same time, medical programs already have a huge workload and little space is available for appropriate training. Others state that nutrition shouldn't fall within the remit of doctors. So how do we reconcile all this?

While this episode focuses on the United States context, the concepts apply to other countries, as it outlines both the challenges and the emerging solutions for closing the nutrition training gap in medicine.

• [03:21] Akash Patel's background and interests
• [05:22] Current state of nutrition education in medical schools
• [07:55] Akash's pilot program and initial findings
• [13:37] Challenges and considerations for curriculum integration
• [15:11] Effective curriculum design for nutrition education
• [23:38] Debating the role of nutrition education in medical training
• [29:00] Practical scenarios and the role of doctors
• [33:58] Advice for implementing nutrition education initiatives
• [38:15] Future directions in nutrition and medicine
• [43:07] Key ideas segment

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• Enroll in the next cohort of our Applied Nutrition Literacy course
• Instagram:
  • @withakashpatel
  • @dannylennon_sigma
  • @sigmanutrition

Never before has there been greater access to information about nutrition and health. But never before has there been such a low barrier to being seen as an "expert". There are large numbers of people getting information from, and basing their health decisions on, people who don't have direct expertise in the field in which they are talking about.

Moreover, some promote the lack of domain expertise as a feature, not a bug. They claim that those that were conventionally seen as domain experts are either brainwashed, lazy in their thinking, or outright corrupt. And the solution is instead to look to those with a fresh perspective that can illuminate us on the "truth".

In this episode, Alan and Danny discuss this "death of domain expertise", how it plays out online, and its ramifications for people's ability to get good information.

Note: This episode was originally published as an exclusive episode for Sigma Nutrition Premium subscribers. If you wish to get more Premium-only episode or read study notes to our episodes, you can subscribe to Sigma Nutrition Premium.

• [03:21] The manufactured collapse of expertise
• [09:58] Understanding domain specific expertise
• [15:10] Cross domain expertise and its limits
• [33:07] The illusion of learning from popular podcasts
• [38:26] The problem with self-proclaimed experts
• [46:11] The challenge of identifying true expertise
• [50:39] The impact of institutional distrust
• [56:30] Navigating the information landscape

• Go to episode page
• Join the Sigma email newsletter for free
• Subscribe to Sigma Nutrition Premium
• Alan Flanagan's Alinea Nutrition Education Hub
• Enroll in the next cohort of our Applied Nutrition Literacy course
• Mentioned books & studies:
  • Tom Nichols – The Death of Expertise
  • Jonathan Haidt – The Righteous Mind
  • Ionnidis, 2018 – The Challenge of Reforming Nutritional Epidemiologic Research