Sigma Nutrition Radio:  Health | Performance | Wel

Sigma Nutrition Radio: Health | Performance | Wel


SIGMA Nutrition Radio: a place where people interested in self-educating themselves in order to take control of their own health, body and performance can get access to honest, science-backed information and opinions from leading experts. Every week the show features deep-diving interviews with amazing guests with expertise in different areas related to nutrition, health, performance, mindset and living life to its fullest potential.


SNR #193: Lyle McDonald - Nutrient Partitioning & Fuel Utilization  

Lyle McDonald

Lyle is the author of the Ketogenic Diet, the Rapid Fat Loss Handbook and the Guide to Flexible Dieting. He has been interested in all aspects of human performance physiology since becoming involved in competitive sports as a teenager. Pursuing a degree in Physiological Sciences from UCLA, he has spent almost 20 years of his life studying human physiology and the science, art and practice of human performance, muscle gain, fat loss and body recomposition.

Over the years, in addition to working with the general public, Lyle has worked primarily with endurance athletes, a few powerlifters, and some bodybuilders. Through his books, articles and his forum, he has helped thousands lose fat, gain muscle and get stronger or perform better.

In This Episode We Discuss:

Fundamentals of calorie partitioning
What actually influences the partitioning of fuel substrates and the fate of the calories we consume
Genetic differences in how much our body composition proportionally changes when either in a hyper- or hypo- caloric diet
Is there anything we can really do to modify this?
Insulin sensitivity in muscle and adipose tissue
Blood glucose responses to meals: For healthy individuals, how much does it matter?
Should you match carbohydrate intake to insulin sensitivity?

SNR #192: Shona Halson, PhD - Recovery Strategies for Elite Performance  

Dr. Shona Halson is the Senior Recovery Physiologist at the ‪Australian Institute of Sport and an Associate Editor of the International Journal of Sports Physiology and Performance. Her work involves providing athletes with advice and assistance to minimise fatigue and maximise recovery, she is responsible for conducting applied research to evaluate techniques to reduce fatigue and increase recovery. Shona has worked closely with the Australian Dolphins and their specific preparation for the Rio Olympics. Shona has a wealth of experience in the area of fatigue and recovery and she spent a number of years working as the Recovery Centre Director for the Australian Olympic Committee.

In This Episode We Discuss: Periodization of recovery Cold water immersion and constrast water therapy for recovery Do recovery strategies have the potential to negatively impact adaptive responses to training? Athlete perception and "belief" in recovery modalities The importance of hydrostatic pressure: implications for hydrotherapy practice Effectively monitoring fatigue in athletes to assess training load and recovery
SNR #191: How to Build a Career in Nutrition Coaching  

How to Build a Career in Nutrition Coaching
For some reason enough people have seemingly deemed me to be “successful” enough to ask me for advice about starting a career in nutrition, usually via some version of one of the following questions:

What nutrition course do you suggest I do?
What qualifications do I need to work as a nutritionist?
I’m a personal trainer/coach, what is the best way to improve my nutrition knowledge and/or my reputation as a nutrition coach?
I currently work in a different field but want to transition to a career in nutrition. How should I go about this? Is it possible?
I’d like to work in sports nutrition. How do I go about this?
So the plan is to address these questions comprehensively in this guide. Which should hopefully help those of you who have similar questions. So let’s get started!

SNR #190: Mike Israetel, PhD - Nutrition Considerations for the Strength Athlete  

Mike Israetel, PhD discusses the relative importance of carbohydrates for strength athletes, planning nutrition periodization for strength athletes and how to structure mesocycles for strength gain.

Mike Israetel is currently a professor of Exercise Science at Temple University in Philadelphia, as well consulting nutritional and training for elite strength and combat athletes around the world. Mike is the head science consultant for Renaissance Periodization, where he has authored and co-authored a number for books. He has a PhD in Sport Physiology from East Tennessee State University, and on the sporting side has experience as a competitive powerlifter, grappler and bodybuilder.

In This Episode We Discuss: Do strength athletes (powerlifters, weightlifters) need full glycogen stores? What roles do carbohydrates serve for such athletes? Nutrition considerations when making weight for a meet Nutritional periodization for the strength athlete: diet early and maintain lower bodyweight, or maintain higher weight before dieting close to the meet? Do the volume landmarks for planning training (MRV, MEV, MAV) still apply for the strength athlete? Are volume increases as important?
SNR #189: Katy Horner, PhD - Gut Hormones, Gastric Emptying & Appetite Regulation  

Katy joined the School of Public Health, Physiotherapy and Sport Sciences at UCD as a lecturer in Sport and Exercise Science in 2017. Katy holds a BSc and MSc in Sport and Exercise Science, both from the University of Limerick, and a PhD in Exercise and Nutrition Sciences from Queensland University of Technology, Australia. She subsequently completed postdoctoral studies in childhood obesity and physical activity at the Children’s Hospital of Pittsburgh, USA and more recently in the Nutrition, Biomarkers and Health Research Group at UCD as part of Food for Health Ireland.

Her research draws on this interdisciplinary background, particularly in terms of trying to make connections across exercise physiology, metabolism and nutrition science. She has published articles on appetite control, gut and exercise physiology in a range of journals across the fields of sports medicine, exercise science, metabolism, obesity and nutrition. Her interest in applied sport and exercise science centres on nutritional advice and exercise prescription for both athletes to optimise performance and to a wide range of other individuals to optimise wellbeing and metabolic health. Katy is also a trained phlebotomist and registered nutritionist (with specialisms in nutrition science and sport/exercise), and currently works with the Ad Astra elite athlete support team at UCD.

In This Episode We Discuss: What you should know about gut peptide hormones (GLP-1, ghrelin, peptide YY) Does the dysregulation of appetite hormones drive excess caloric intake and hence excess bodyfat accumulation, or is it excess bodyfat accumulation that drives hormonal dsyregulation? The effects of exercise interventions on these appetite-related gut peptides Active and inactive men differ in processes of food reward Habitual exercise could contribute to weight management by altering processes of food reward via the gut-brain axis What is gastic emptying and how do we measure it? Do people who exercise compensate for the increase in energy expenditure via compensatory increases in hunger and food intake? Implications of gastric emptying on exercise performance
SNR #188: Barbara Oakley, PhD - How to Learn, Study & Get Better With Science  

Barbara Oakley is a Professor of Engineering at Oakland University. She is involved in multiple areas of research, ranging from STEM education, to Engineering education, to learning practices.

Most recently, Professor Oakley has co-created and taught Learning How To Learn: Powerful mental tools to help you master tough subjects, the world's most popular online course. She also has written a number of books, including: 'A Mind For Numbers' and 'Mindshift'.

In This Episode We Discuss: Focused mode vs. diffuse mode for thinking, problem solving and working Environments for productive learning: distractions, timelines and procrastination "Neural chunking" and creating patterns for developing skills Preventing regression of knowledge and skill acquisition Advice for improving scientific literacy/proficiency and confidence in reading/understanding science How to soak up (and retain) more information from podcasts
SNR #187: Katie Anne Rutherford – The Importance of Perspective in Chasing Strength & Physique Goals  

Katie Anne started her initial athletic endeavors in high school; running track and cross country before transitioning into bodybuilding while attending college at The Ohio State University.

Her first contest prep and powerlifting meet both took place in 2014. In her first season of competing, she came away with two first place wins in figure, a powerlifting meet win, and her IFPA figure pro card.

Katie Anne is currently an elite USAPL 72kg powerlifter, IFPA Natural Figure Pro, and coach. She was the 2015 USAPL Raw Nationals 72kg Junior National Champion.

In This Episode We Discuss: Katie Anne’s background in athletics and her transition to bodybuilding and powerlifting The trap for athletes of putting all their self-worth into their athletic acheivement Gaining perspective and focusing on the process when chasing goals Advice on how to women can deal with scale weight increases when building muscle How attitude and positivity are a skill, and like any skill need to be practised 
SNR #186: Dr. Jake Kushner, MD - Nutrition for Type 1 Diabetes  

Dr. Jake Kushner is leading the efforts in Diabetes and Endocrinology at Texas Children's Hospital. Dr. Kushner is a McNair Medical Institute Scholar at the Baylor College of Medicine. As the Chief of Pediatric Diabetes and Endocrinology at Baylor College of Medicine, he is a major thought leader in type 1 diabetes care and research. His overarching career goal is to help children and young adults with diabetes and other endocrine disorders live long, healthy lives. His administrative priorities focus upon developing and promoting innovative new models of patient-centered care, education, and cutting edge research.

A graduate of the University of California at Berkeley, Dr. Kushner earned his medical doctorate from Albany Medical College in New York. He completed a residency in pediatrics at Brown University. He then completed a clinical fellowship in Pediatric Endocrinology at Children's Hospital Boston, Harvard Medical School, followed by a 5-year research fellowship at the Joslin Diabetes Center at Harvard Medical School.

Prior to arriving at the Baylor College of Medicine Dr. Kushner was at the University of Pennsylvania School of Medicine and the Children's Hospital of Philadelphia (CHOP). Dr. Kushner has received national awards, including elected membership to the prestigious American Society of Clinical Investigation. He currently serves as the president of the Society for Pediatric Research. Dr. Kushner's research has been supported by the National Institutes of Health, the Juvenile Diabetes Research Foundation and the March of Dimes, amongst other sources. His clinical interests include the care of children with type 1 diabetes.

Dr. Kushner's research is focused upon of the insulin-secreting beta cells of the pancreas. A major theme of the Kushner lab includes studies to understand the origins of adult beta cell growth and regeneration. Until recently it was not clear exactly where adult beta cells came from during postnatal life. Dr. Kushner and colleagues have carried out studies in adult mice with a variety of advanced tools. In contrast to the dominant views, they do not observe any contribution to beta cell growth in adult mice from "tissue stem cells". Instead, they find that beta cells expand by simple division "self-renewal". Dr. Kushner and colleagues are currently extending this work, with the goal of studying beta cell regeneration under a variety of normal and disease conditions.

In This Episode We Discuss: The intricacies of type 1 diabetes Beta cell dysfunction Nutritional approaches to type 1 diabetes: standard care and carbohydrate restriction Issues with low-carb for T1D: hypoglycaemic episodes? ketones? long-term safety unknown? "Low carb is not for everyone with T1D. Frankly, there is so much that we don’t know. But, low carb management of T1D can be quite advantageous for those who choose it." - Jake Kushner, MD
SNR #185: Trent Stellingwerff, PhD - Nutrition Strategies for Endurance Sports  

Trent is an applied sport physiologist with a specialization in the area of performance nutrition. He earned a Bachelor of Science in Human Nutrition and Exercise Physiology at Cornell University and he earned his Ph.D. from the University of Guelph in Exercise and Skeletal Muscle Physiology.

In his current role he focuses on providing his physiology and nutrition expertise to Canada’s national rowing, track and field and triathlon teams, as well as leading Canadian Sport Institute’s Innovation and Research division. Trent previously worked as the senior leading scientist in Performance Nutrition for Power Bar at the Nestle Research Center in Lausanne, Switzerland. An experienced researcher, Trent has more than 40 peer-reviewed scientific publications and is currently on the editorial board for the International Journal of Sports Physiology and Performance and International Journal of Sports Nutrition & Exercise Metabolism. He has co-authored six book chapters focusing on the role that nutrition can play in supporting elite athlete performance, including a chapter on ’Nutrition for the Endurance Athlete’, for the newest version of the 2013 IOC Sports Nutrition Encyclopaedia. His expertise is paired with his ability to deliver complex scientific concepts in an informative and applicable way. He co-supervises a number of master and PhD student collaborative research projects at UBC, UVIC and Guelph.

Trent has attended many World Championships and Olympic Games as part of Team Canada’s Integrated Support Team and consults several Olympic athletes from around the world, including his wife Hilary, who competed for Canada in the 1500m at the 2012 Games.

SNR #184: Uncertainty About Artificial/Non-Nutritive Sweeteners (Listener Question Episode)  

We take a deeper look at artificial/non-caloric sweeteners; effects on bodyweight, glucose tolerance, gut flora and health. What does the evidence say about safety and health concerns?

All references are linked to in the show notes page at

SNR #183: Arthur Lynch & Eoghan McNeill - Sports Psychology in Self-Paced/Closed-Skill Sports  

Sigma coach Arthur Lynch interviews sport psychology PhD researcher Eoghan McNeill of the University of Limerick on applying evidence-based sports psychology techniques to improve performance, particularly in powerlifting and other self-paced/closed skill sports.
Eoghan is a PhD researcher in the PESS department at the Univeristy of Limerick. Eoghan's research examines improving performance in self-paced sports (focusing on golf) through psychology techniques and mental preparation. Eoghan has a MSc. in Sport and Exercise Psychology from Ulster University, Jordanstown (UUJ). Eoghan can be contacted at

In This Episode We Discuss:

Pre-performance routine and the importance of conscious thought
Use of first-person and third-person imagery for performance and skill acquisition
Effective self-talk
Thought replacement strategy and reframing negative thoughts

SNR #182: Reid Reale, PhD - Research on Water Loading & Making Weight Practices in Combat Sport  

Reid recently completed a PhD, focusing on weight cutting techniques and body composition of combat sport athletes. This work was carried out in conjunction with the Australian Institute of Sport, where research is combined with helping elite level Olympic athletes. Reid has a master’s degree in dietetics and holds Accredited Sports Dietitian and Accredited Practising Dietitian status with Sports Dietitians Australia and the Dietitians Association of Australia respectively.  He won first prize in the “Young investigator award” at the 2016 European College of Sports Science annual congress in Vienna, for his presentation ‘Rapid weight loss in Olympic combat sports’.

On the sporting side, Reid started training BJJ in 2006 and received his black belt in 2015 from Prof. Chris Derksen of the Peter De Been lineage. He is an active competitor having fought in hundreds of BJJ competition matches and winning gold medals at every belt level. His most notable and recent achievements include 2016 UAEJJ World Pro Trials Black Belt Heavyweight champion (Sydney, Australia), 2015 Asian Open Brown Belt heavy weight silver medallist (Tokyo, Japan), 2015 Pan Pacific Brown Belt open weight champion (Melbourne, Australia).

In This Episode We Discuss: Why cut weight? Methods used to cut weight The mechanisms by which water loading can potentially be useful in weight cutting Low residue diets and acute weight loss Deciding how much to cut for each sport
SNR #181: Jeff Nippard - Intuitive Eating, Control-Based Eating & Body Recomposition  

Jeff Nippard is a WNBF Pro Drug-Free Bodybuilder and internationally qualified IPF/CPU Powerlifter in the 74 kg class. He earned the title of Mr. Junior Canada for natural bodybuilding in 2012 under the guidance of Dr. Layne Norton. Prior to earning the Canadian national title, Jeff was a two-time Mr. Junior Newfoundland title-holder for 2009 and 2010. As a powerlifter, Jeff has claimed a 227.5 kg (502 lb) squat, 152.5 kg (336 lb) bench press (2014 Canadian national record) and a 235 kg (518 lb) deadlift with an all time best Wilks score of 446.

With a Bachelor of Science degree in biochemistry, Jeff has gathered the requisite scientific knowledge to compliment his practical experience acquired through training and coaching. Jeff worked as a coach with esteemed online coaching group The Strength Guys through 2014 and 2015 before branching out with STRCNG. Jeff has coached women's bikini and men's bodybuilding national and provincial champions, professional natural bodybuilders and nationally and IPF Worlds qualified raw powerlifters.

In This Episode We Discuss:

Intuitive eating vs. ad libitum eating Accurately defining intuitive eating Using intuitive eating whilst making physique progress Factors that influence whether intuitive eating or control-based eating is the best tool Long-term planning for body recomposition
SNR #180: Jason Gill, PhD - Role of Ethnicity in Cardio-Metabolic Disease Risk  

Dr Jason Gill is a Reader in Exercise and Metabolic Health in the Institute of Cardiovascular and Medical Sciences at the University of Glasgow. He leads an active multi-disciplinary research group investigating the effects of exercise and diet on the prevention and management of vascular and metabolic diseases from the molecular to the whole-body level. Major research interests include: why certain population groups (particularly South Asians) appear to be particularly susceptible to the adverse effects of a `Westernised' lifestyle, and how lifestyle interventions can modulate this excess risk; the interactions between physical activity, energy balance, adiposity and disease risk; and the mechanisms by which exercise regulates lipoprotein metabolism.

He is a past Chair of the British Association of Sport and Exercise Sciences (BASES) Division of Physical Activity for Health and a member of the development groups for the Scottish Intercollegiate Guidelines Network (SIGN) guidelines for the prevention and treatment of obesity and for prevention of cardiovascular disease. Jason is Director of the MSc programme in Sport and Exercise Science & Medicine, and also plays an active role in communicating the science of physical activity, diet, obesity and cardio-metabolic risk to the widest possible audience including a number of appearances on TV documentaries and organisation of Understanding of Science events for the general public.

In This Episode We Discuss: Modifiable factors that influence cardio-metabolic disease risk Differences in diabetes and cardio-metabolic disease risk between different ethnic groups Is this increased disease risk a function of ethnicity alone or a mismatch between the environment and that populations evolutionary past? How different BMI values correspond to different levels of risk between ethnic groups Differences in cardiorespiratory fitness levels and capacity for fat oxidation potentially contribute to ethnic differences in the cardio-metabolic risk profile Do we need ethnicity-specific physical activity guidelines? Research questions that remain unanswered
SNR #179: What Interviewing the Best Minds in Evidence-Based Nutrition & Fitness Has Taught Me About Them  

Episode 179: Patterns that I've recognised and traits that are common to the best people in evidence-based nutrition and fitness.

SNR #178: Listener Input, Future Plans & Latest News  

Episode 178: I need your input as a valued listener! I talk through some exciting new plans, ideas and where we as a community should aim to bring this podcast.

SNR #177: Chris & Eric Martinez - Habits, Mentality & the Self-Improvement Side of Fitness  

Chris and Eric Martinez are the founders of Dynamic Duo Training. The twin brothers have the knowledge, the credibility, the passion, the “in the trenches” experience training themselves and clients, and have been mentored under some of the most prestigious coaches in the industry such as Layne Norton, Eric Helms, and Dr. Joe Klemczewski. Chris and Eric are constantly striving to innovate, learn to be better in all areas of life, evolve, and most importantly execute and serve to their clients. They recently authored the book 'The New Era of Fitness'.

In This Episode We Discuss: The components that comprise the "new era of fitness" Forming new habits with clients Mentality towards fitness goals Why personal development is important How to improve yourself Lessons learned through experience and education
SNR #176: Eric Trexler - Citrulline & Nitrate Supplements for Performance  

Eric Trexler is a PhD student at UNC Chapel Hill, under Dr. Abbie Smith-Ryan. He has a research focus on how exercise and nutrition affect metabolism, performance, and body composition. Eric comes from a background in natural bodybuilding, powerlifting, and strength coaching, and currently holds certifications in sports nutrition (CISSN) and strength and conditioning (CSCS). Eric completed his undergraduate degree at The Ohio State University, and his master’s degree at UNC Chapel Hill.
In This Episode We Discuss:

Proposed mechanisms of action of citrulline
Citrulline malate vs. L-citrulline
Nitric oxide "boosters"
Why arginine is ineffective
Dietary nitrates and nitrate supplementation via beetroot/pomegranate
What athletes might this work for?
Research on cordyceps supplementation for exercise performance

SNR #175: Prof. Klaas Westerterp - Metabolism, Energy Expenditure & Weight Regulation  

Klaas Westerterp is Professor of Human Energetics at Maastricht University. His field of expertise is energy metabolism, physical activity, food intake and body composition, and energy balance under controlled conditions and in daily life. He is member of the Editorial Board of the journal Nutrition and Metabolism (London), the European Journal of Applied Physiology, the European Journal of Clinical Nutrition, and Editor-in-Chief of the Proceedings of the Nutrition Society.

SNR #174: Jorn Trommelen – Carbohydrate Oxidation During Exercise & Pre-Sleep Protein  

Episode 174: Researcher from Maastrict University, Jorn Trommelen is on the show to discuss his research on the effect of glucose/fructose on carbohydrate oxidation during exercise and the effect of pre-sleep protein on muscle protein balance.
Jorn earned his MSc in Nutrition and Health with top honors at Wageningen University & Research Centre. He is now pursuing a PhD in Muscle Metabolism at Maastricht University, at one of the leading laboratories in that field.

His research focusses on protein ingestion to optimize post-exercise muscle protein synthesis. In addition, he investigates carbohydrate metabolism during and after exercise.

Jorn won several awards for his research including:

A Young Investigator Award at the European College of Sport Science Congress in 2015 The GSSI Sport Nutrition Award at the American College of Sports Medicine in 2016 The Gail E. Butterfield Nutrition Travel Award at the American College of Sports Medicine in 2016 A GSSI Nutrition Award at the European College of Sport Science Congress in 2016
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