Introduction
Performance nutrition in elite sport is often discussed in terms of meal plans, supplements, and macronutrient targets. However, effective practice in professional environments depends just as much on education, trust, communication, and the ability to translate scientific principles into decisions athletes can act on under real-world constraints.
In this episode, Dr James Morehen discusses his work across elite rugby, football, and combat sports, with particular attention to the demands of professional rugby. The conversation explores how practitioners support athletes in a high-impact collision sport, including fuelling for training and match play, managing body composition without reducing athletes to arbitrary numbers, addressing recovery from muscle damage and injury, and developing practical systems around game-day nutrition.
The episode also provides insight into the realities of building a career in performance nutrition, including the importance of applied experience, interdisciplinary collaboration, and learning how to coach athletes rather than simply prescribe to them.
- [03:31] Interview starts
- [10:26] Educating athletes on nutrition
- [13:55] Breaking into elite sport
- [26:26] Physiological demands of rugby
- [30:53] Energy needs and timing
- [38:28] Body composition measurements: utility?
- [46:16] Game day fuelling strategy
- [01:07:09] Key ideas (premium-only)
Episode Resources
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Guest Information
James Morehen, PhD is a performance nutritionist working in elite rugby, currently as the head nutritionist for England Rugby. He also currently works with Bristol Bears across senior men’s, senior women’s, and academy squads. His pathway into sport nutrition began at Liverpool John Moores University, where he completed undergraduate, master’s, and doctoral studies focused on applied physiology, rugby, body composition, and performance nutrition. He has since worked across elite environments including professional rugby league, England Football, Bristol Bears, England Rugby, and professional boxing, developing a practitioner style centred on education, athlete trust, and translating science into practical strategies for training, competition, body composition, recovery, and long-term performance.
Study Notes
Dr James Morehen explains how effective performance nutrition depends on translating science into practical systems that athletes can understand, trust, and consistently apply.
Useful Terminology
- Pedagogy: The theory and practice of teaching.
- Fuel for the work required: A principle in sports nutrition whereby energy and carbohydrate intake are adjusted to match the demands of the upcoming training, match, or recovery period.
- Energy availability: The amount of dietary energy remaining for physiological function after accounting for exercise energy expenditure.
- Impact-induced muscle damage: Muscle damage arising from collisions, tackles, and other contact events.
- Exercise-induced muscle damage: Muscle disruption caused by high-intensity running, acceleration, deceleration, sprinting, and change of direction.
- Functional mass: A practical concept used to describe body mass that contributes positively to rugby performance.
- Bioelectrical impedance: A body composition assessment method that estimates tissue and fluid compartments by passing a small electrical current through the body.
Performance Nutrition as Coaching, Education, and Behaviour Change
- Performance nutrition should not be reduced to food lists, supplement schedules, or prescriptive meal plans.
- The practitioner’s role is educational and relational: athletes need enough understanding to make
