Expert Panel Members

Annually, GSSI invites subject matter experts to serve on an Expert Panel. The members below represent the 2023 Expert Panel.

Lawrence Spriet, PhD - GSSI XP Chair

University of Guelph, Ontario, Canada


Dr. Lawrence Spriet is a professor at the University of Guelph in Canada. His research examines how skeletal muscle generates the large amounts of energy needed to exercise and perform in work and sport situations.
Lawrence is recognized as one of the leaders in the field of exercise metabolism and has published extensively on this topic. In addition to his fundamental research, his applied research examines whether compounds that are purported to be “ergogenic” or “work enhancing” agents actually augment muscle metabolism and/or improve human performance. He also conducts hydration/sweat testing and research aimed at counteracting the effects of dehydration in athletes engaging in stop-and-go sports like ice hockey, basketball and soccer. Dr. Spriet has had a long history with GSSI, first coming on board in 1990, helping establish the Canadian GSSI Branch in 2005 and acting as Chair of XP since 2012.

XP Panel role

GSSI XP chair and SSE Editor-in-Chief

Marco Altini, PhD

HRV4 Training, NL


Marco holds a PhD cum laude in applied machine learning, a M.Sc. cum laude in computer science engineering, and a M.Sc. cum laude in human movement sciences and high-performance coaching. He has published more than 50 papers and patents at the intersection between physiology, health, technology and human performance. He is the co-founder of HRV4Training, advisor at Oura, guest lecturer at VU Amsterdam, and editor of the Wearables department of IEEE Pervasive Computing. He loves running. 

XP Topic

Framework for Collecting Wearable Data

Carolyn Braff

VP of Culinary, PepsiCo Foods, USA


Carolyn Braff is a seasoned brand strategist at Gatorade who has driven innovation, consumer engagement and go-to-market programming since joining the leading sports fuel brand in 2013. Braff was named Head of Brand Strategy in 2021 where she leads Gatorade's marketing efforts across its portfolio of products and also sits on the brand’s Women’s Advisory Board.

In her nearly decade-long stint at Gatorade, Braff has been instrumental in the development of brand strategy for marquee product platforms, including Gatorade Thirst Quencher, Gatorlyte, Gatorade Fit and G Zero. In her pervious roles at the brand, she oversaw the launch of Gatorade’s first zero sugar product, Gatorade Zero, which reached $1B in sales in year two, and developed go-to-market strategies that have fueled Gatorade’s double digit global volume growth. She also led the brand’s portfolio of performance nutrition brands, including Gatorade protein and Muscle Milk, as well as the Endurance business.

Prior to her tenure at the brand, Braff began her career as a sportswriter in New York City, covering college football for CBS Sports' college network. She also held editorial positions with the Sports Video Group.  

A Philadelphia native, Carolyn received her BA from Columbia University in Urban Studies and Spanish Language and Literature. She joined Gatorade after earning her MBA from the University of Chicago Booth School of Business. She lives in Chicago with her husband and two children.

Carolyn has recently accepted the new position of Vice President of Culinary within PepsiCo Foods North America.

XP Topic

Women Athletes: A Business Perspective


Xavi Cortadellas

Gatorade Athletic Equipment GM


Currently Xavi leads the new Gatorade Athletic Equipment Business Unit. Xavi is in charge of creating the growth vision for Gatorade to expand reusable vessels, coolers, smart tech, and other non-consumable verticals. Xavi's team designs a new way to fuel athletes: more sustainable, leveraging DTC, Technology and Digital Platforms and fully integrating vessels with powders, pods and tablets. Xavi leads a multifunctional team, including brilliant marketers, brand managers, product managers, and industrial and brand designers. Xavi has held multiple roles in his 12 years at Gatorade, starting with Global Brand Design and always combining Design, Innovation, and Marketing.

Xavi was born in Barcelona, where he earned a degree in Architecture. He has a strong sports performance and design background from his 11 years of experience with Nike Spain, Mexico, and Brazil. He also has been invited as guest speaker and panelist in multiple Sports and Innovation conferences and has collaborated in different Podcasts and Articles. As part of his Innovation curriculum, he holds several invention patents.

XP Topic: 

Gatorade: The Technology Vision

Kirsty Elliott-Sale, PhD

Manchester Metropolitan University, Manchester, UK


Kirsty completed her undergraduate degree and PhD [Exercise Physiology] at Liverpool John Moores University. Her PhD examined the effects of female reproductive hormones on muscle strength and since then her work has primarily focused on female athletes. She worked as a Lecturer at Brunel University and the University of Brighton, before undertaking a four-year Post-Doctoral Research Fellowship at Kings College London. She worked at Nottingham Trent University from 12 years, before joining the Institute of Sport at Manchester Metropolitan University in 2022 as a Professor of Female Endocrinology and Exercise Physiology. In addition to her research on female athletes, which includes the menstrual cycle, hormonal contraceptives, the Female Athlete Triad and Relative Energy Deficiency in Sport, her work in recent years has involved designing and implementing exercise interventions during and following pregnancy in a variety of populations including servicewomen (i.e., military personnel), athletes, and women with obesity. She has co-authored numerous peer-reviewed journal articles, book chapters, expert statements, and editorials on/for sportswomen. In addition, she works with many organisations such as the English Institute of Sport, the Football Association, The Australian Institute of Sport, The European Club Association, and The Wu Tsai Performance Alliance and is part of several special interest groups and advisory boards related to female athletes.

XP Topic

History, Hormones and Women Athletes


Stavros Kavouras, PhD

Arizona State University, Arizona, USA


Dr. Kavouras is a Professor of Nutrition and Assistant Dean of graduate education for the College of Health Solutions at Arizona State University. He is the founding director of the Hydration Science Lab, which studies how water intake impacts health and performance.

Dr. Kavouras is one of the top 2% of the world's most cited scientists, the author of more than 160 peer-reviewed articles, cited more than 11,000 times (h-index 57), and has given lectures in 29 countries. His current research focuses on:

  • hydration and glucose regulation

  • fluid composition for optimizing hydration

  • children’s hydration

He is the Editor-in-chief of the Hydration section for Nutrients, a section editor of the European Journal of Nutrition, and associate editor of Frontiers in Nutrition. Professor Kavouras is a fellow of the National Academy of Kinesiology (#637), the American College of Sports Medicine, and the European College of Sports Science. He is also an elected member of the American Society of Nutrition, the Obesity Society, and the American Physiological Society.

XP Topic

Hydration: The Foundation for 24/7 Nutrition

Sara Oikawa, PhD

Gatorade Sports Science Institute, Florida, USA


Sara Oikawa is an R&D Associate Principal Scientist at the Gatorade Sports Science Institute (GSSI) satellite lab at IMG Academy in Bradenton, Florida.  Sara earned her Honours Bachelor of Science in Kinesiology, Masters of Science in Kinesiology, and her Ph.D. in Kinesiology at McMaster University in Hamilton, Canada. Sara has worked with a wide variety of populations including healthy young and older adults, pregnant women, cardiovascular rehabilitation patients, and elite athletes. She has also studied several physical activity models such as resistance exercise, inactivity and HIIT, to investigate skeletal muscle protein metabolism. Specifically, Sara is interested in the impact of dietary protein quality on muscle protein synthesis through alterations in physical activity. 

Sara leads the GSSI Claims program for the Gatorade Performance Portfolio and supports the management of GSSI External Research. In her spare time, Sara enjoys travelling, hiking, and cheering for Toronto-based sports teams.

XP Topic

Nutrition for Athlete Wellness: A Product Development and Claims Perspective

Jen Sygo, MSc, RD

Cleveland Clinic, Canada


Jennifer Sygo is a dietitian, sports nutritionist, author, and speaker specializing in nutrition for prevention and performance. After completing an undergraduate degree in Biochemistry at McMaster University and a Masters of Science in Human Biology and Nutritional Sciences, specializing in Nutrition, Exercise, and Metabolism from the University of Guelph, Jennifer joined the team at Cleveland Clinic Canada in 2006, where she uses evidence-based strategies to help busy professionals, athletes, and active individuals make simple dietary changes to improve their health and performance, and reduce their risk of disease. A leading sport nutritionist, Jennifer works with athletes ranging from weekend warriors to athletes in the NBA, NHL, Major League Baseball, and professional tennis.  She has provided nutrition services for the Toronto Maple Leafs and Triathlon Canada, and currently serves as team dietitian for the Toronto Raptors, Athletics Canada, Swimming Canada, and Gymnastics Canada. Jennifer is also a popular speaker and seminar leader, and provides presentations and keynote addresses for major corporations and conferences.  Jennifer's nutrition expertise is routinely featured in the media, including The National Post, The Toronto Star, and CBC's The National.  In 2014, Jennifer's first book, "Unmasking Superfoods:  the Truth and Hype about Acai, Quinoa, Chia, Blueberries, and More", was published by HarperCollins Canada, and became a national best-seller. Outside of her work, Jennifer is an avid sports enthusiast, and a proud mother of two young boys.

XP Topic

Fueling Women Athletes

Matt Tenan, PhD

Rockefeller Neuroscience Institute, West Virginia, USA


Matt Tenan is the Program Director for Human Performance & Data Science at the Rockefeller Neuroscience Institute. With a background in Athletic Training (B.S. Ithaca College), Exercise Physiology (M.A. University of North Carolina-Chapel Hill), Neuroscience (Ph.D. University of Texas-Austin), and Statistics (Fellowship at University of Texas-Austin), Matt brings a unique perspective on modeling human performance from the league-level down to the cellular-level. Having worked in both Army R&D and medical data science, his focus is constantly on delivering data products which enhance performance and mitigate injury. Matt serves as an Editor for two preeminent journals in the field of human performance: Sports Medicine and the Journal of Strength & Conditioning Research.

XP Topic

Generating Real-World Evidence in Sport

Benjamin Wall, PhD

University of Exeter, Exeter, UK


Benjamin Wall obtained his BSc from the University of Birmingham and his PhD from the University of Nottingham Medical School, where his thesis addressed the integration of fat and carbohydrate metabolism during exercise. Thereafter, Benjamin worked as a post-doctoral fellow at Maastricht University Medical Centre in the Netherlands where he studied the nutritional regulation of muscle mass in health and disease before taking up a faculty position at the University of Exeter, UK, in 2013. Benjamin is now Professor of Nutritional Physiology at the University of Exeter, where his research interests concern how nutrition and physical (in)activity influence muscle mass, metabolic health and performance in a variety of populations. Benjamin’s current research projects are focused on how inactivity and ageing alter the capacity of muscle tissue to utilise nutrients, and how this can inform on optimising nutritional requirements for injured athletes, hospitalised patients and in support of healthy ageing. A particular interest is placed on developing an evidence base around novel and sustainable dietary protein sources in various populations.

XP Topic

Alternative Forms of Protein for Recovery