Dr Gareth Wallis PhD, FHEA

Dr Gareth Wallis

School of Sport, Exercise and Rehabilitation Sciences
Senior Lecturer in Exercise Metabolism and Nutrition

Contact details

School of Sport, Exercise and Rehabilitation Sciences
University of Birmingham
B15 2TT

Dr Wallis is an Exercise Scientist with major interests in Nutrition and Metabolism. He studies dietary influences on exercise metabolism, with a particular focus on macronutrients and their roles in performance, training adaptation and health.

Feedback and office hours

For University of Birmingham students only, please email to arrange an appointment.


  • BSc (Hons.) Sport and Exercise Sciences (University of Birmingham)
  • MSc (Dist.) Exercise Physiology (Loughborough University)
  • PhD Sport and Exercise Sciences (University of Birmingham)
  • Fellow, Higher Education Academy (UK), 2015 – present


Dr Wallis’s basic training was in Sport and Exercise Sciences (Birmingham) and Exercise Physiology (Loughborough). Initially, he worked as a Sport Science practitioner delivering physiology support for high performance athletes (Human Performance Unit, University of Birmingham, 2001-2002) before commencing his PhD at Birmingham in the area of Exercise Metabolism and Nutrition. His doctoral studies, conducted under the direction of leading sports nutritionist Professor Asker Jeukendrup, focused on ‘Exercise Metabolism and Carbohydrate Ingestion in Men and Women’. Aspects of this research have made significant contributions to current Sports Nutrition guidelines for endurance athletes and impacted on nutritional product development in the sport nutrition manufacturing industry.

Dr Wallis conducted post-doctoral studies in the laboratory of world-leading exercise physiologist Professor George Brooks in Department of Integrative Biology at the University of California, Berkeley. There, he researched in a broad range of areas related to whole-body and organ specific metabolic regulation in health and disease and during this time was awarded a Senior Research Training Fellowship from the American Lung Association.

Before joining the School, Dr Wallis worked as a Principal New Product Research Scientist at GlaxoSmithKline (GSK) Nutrition based in the UK (2008-2011). In this role he provided strategic scientific input, technical oversight and undertook human volunteer research study management in a scientific program developing innovative new product and claims opportunities for GSK Nutrition, with a particular emphasis on sport and exercise science/nutrition.

Dr Wallis joined the School of Sport, Exercise and Rehabilitation Sciences at the University of Birmingham in November 2011. In this role he conducts research and teaching in the area of exercise metabolism and nutrition in the context of health and sporting performance.


Dr Wallis coordinates a module in Sports Nutrition, available to undergraduate students at the University of Birmingham studying BSc (Hons) Sport and Exercise Sciences. He also supervises BSc and MSc student projects in areas aligned with his research interests. 

Postgraduate supervision

Current research supervision as lead supervisor:

Nurul Abdullah, 2015 – present, Nurul’s PhD research is focussed exploring metabolic response to food ingestion and exercise in men and women. She is supported by an Education Scholarship from the Malaysian Government.

Brandon Shad (Joint-supervisor with Professor Janice Thompson; collaboration with Professor Luc van Loon [Maastricht]), 2015 – present. Brandon is undertaking a PhD investigating the influence of physical activity and sedentary time on skeletal muscle protein anabolism, physical function and metabolic health. His studentship is funded by the College of Life & Environmental Sciences (University of Birmingham), Exercise as Medicine Doctoral Training Centre.

Tim Podlogar, 2016 – present. Tim’s PhD focusses on the influence of carbohydrate nutrition on exercise metabolism, performance and training adaptation. He is funded by a scholarship from the Slovenian Government.

Ollie Odell, 2017 –present. Ollie is undertaking a PhD in exercise metabolism and nutrition as part of the BBSRC Midlands Integrative Biosciences Training Partnership. This work is being conducted in collaboration with an industrial partner, Volac International Ltd.  

Research student completions as lead supervisor:

Mr Ed Maunder, MRes in Exercise & sport Sciences (2018). Research area: Recovery of endurance running performance with post-exercise maltodextrin-fructose provision. Current post: PhD student, Auckland University of Technology, New Zealand

Dr Gareth Fletcher, PhD in Sport and Exercise Sciences (2017). Research Area: Dietary influence on exercise metabolism, health and performance. Current post: Postdoctroal Researcher, Garvan Institute, Australia

Dr Scott Robinson, PhD in Sport and Exercise Sciences (2016). Research Area: Fat oxidation during exercise: significance, determinants and response to nutrition. Current post: Consultant Performance Nutritionist

Mr Jack Conway, MRes in Exercise and Sport Sciences (2015). Research area: Resistant starch, exercise and insulin sensitivity. Current post: Secondary School teacher.

Dr Helen Bradley, PhD in Sport and Exercise Sciences (2013). Research area: Exercise, insulin sensitivity and GLUT4 translocation in human skeletal muscle. Current post: Clinical Trials Project Manager, Manchester Academic Health Science Centre


Dr Wallis is an Exercise Scientist with major interests in Nutrition and Metabolism. His main goal is to better understand how nutrition can be manipulated to enhance metabolic or adaptive responses to exercise, with a particular focus on macronutrients and their roles in performance, training adaptation and health. To study these areas he utilises a range of experimental approaches that enable detailed profiling of metabolic responses to exercise and nutrition intervention in humans. This includes exercise testing, nutritional intervention, stable isotope tracer administration, biological tissue/fluid collection and a range of analytical techniques including mass spectrometry and molecular biology approaches.

Major research projects:

  • Exploring novel uses for lactose constituents in sports nutrition. Funder: US National Dairy Council. Dates: Sept 2017-Aug 2019
  • Exploring novel nutritional uses for side-stream whey products from cheese production. Funder: BBSRC Doctoral Training Partnership iCASE (partner – Volac International Ltd); Dates: Sept 2017 – Sept 2021
  • Metabolic signatures of nutrient-exercise interactions in human plasma. Funder: Wellcome Trust Institutional Support Fund; Dates: May 2016 – Aug 2016.
  • The effect of dietary carbohydrate manipulation following post glycogen depleting exercise on substrate oxidation at rest and during exercise. Funder: Lucozade Ribena Suntory Ltd; Dates: Aug 2015 – July 2017
  • Aerobic exercise training in the overnight fasted state: a practical nutritional strategy to augment intramyocellular triglyceride turnover in human obesity? Funder: Allen Foundation Inc., USA; Dates: Jan 2015 – Dec 2016
  • Revealing novel nutritional strategies to modulate fuel metabolism. Funder: BBSRC iCASE (partner – GlaxoSmithKline); Dates: Oct 2012 – Sept 2016

My core group consists of the research students described above, along with a Postdoctoral Research (Dr Sam Impey) and Senior Analytical Technician (Dr Sewa Abdullah).

Current external collaborators:

Prof Luc van Loon [Maastricht, NL]

Dr David Rowlands [Massey, NZ]

Dr Andrew Philp [Garvan Institute]

Dr Ed Chambers/Professor Gary Frost [Imperial, UK],

Dr Javier Gonzalez [Bath, UK]

Current internal collaborators:

Professor Janice Thompson 

Professor Martin Hewison 

Dr Konstantinos Manolopoulos 

Dr Alice Turner 

Other activities

Grant review:

  • BBSRC project grant review (2018)
  • Diabetes UK grant review (2017)
  • International Grant Review Panel for NWO-FAPESP (Netherlands/Brazil) call on Data driven approaches to sport and active living, Amsterdam, October 2016.
  • Medical Research Council (UK) project grant review (2016),

Editorial board: Associate Editor for Frontier in Nutrition (Sport and Exercise speciality section), 2017 – present.

Peer-review (2011-present): Regular peer reviewer for several journals including American Journal of Physiology, Journal of Applied Physiology, PLoSOne, European Journal of Applied Physiology, Experimental Physiology,  Medicine and Science in Sports and Exercise, International  Journal of Sports Nutrition and Exercise Metabolism, European Journal of Sport Sciences, International Journal of Sports Medicine, Sports Medicine.

Learned society representation: Physiological Society Institution Rep, July 2016 –present

Outreach (all whilst employed at University of Birmingham):

  • Obesity Wars: Fatness vs. Fitness. Co-applicant and co-organizer of this public engagement event held at ThinkTank Birmingham, funded by Physiological Society, 2014
  • College of Life & Environmental Sciences World Cup Outreach day. Delivered workshops for primary school children around sports nutrition and football in relation to Brazil World Cup, 2014


University Human Tissue Oversight Committee (2015 – present)

MRC Confidence in Concept and Proximity to Discovery (Institutional Funding Support) Steering Group (2014-present)

Academic lead – School of Sport, Exercise and Rehabilitation Sciences Mass Spectrometry Facility (2012-2018)

Research Committee Member, School of Sport, Exercise and Rehabilitation Sciences (2014-2017)

Collaborative Provisions Officer for degree programmes run in concert with the Professional Golfers Association (2014-2017)

Business Links Lead - School of Sport, Exercise & Rehabilitation Sciences (2013- 2017)

Health, Safety and Ethics Committee Member - School of Sport, Exercise & Rehabilitation Sciences (2012-13)


Aston Villa Football Club. Sports Nutrition consultancy (Summer 2017)

Coldeportes (Colombian Sports Institute). International advisor - unification of physiological testing guidelines for elite Colombian athletes (Bogota, Sept 2013).

Sugar Nutrition UK. Commissioned literature review on sucrose and sports performance (Jan-May 2012).


Journal articles published

  1. Newell ML, Wallis GA, Hunter AM, Tipton KD, Galloway SDR. Metabolic responses to carbohydrate ingestion during exercise: associations between carbohydrate dose and endurance performance. Nutrients, 10(1), pii:E37.
  2. Maunder E, Podlogar T, Wallis GA. Postexercise fructose-maltodextrin ingestion enahnaces subsequent endurance capacity. Medicine and Science in Sports and Exercise, 50(5):1039-45, 2018.
  3. Jackman S, Witard OC, Philp A, Wallis GA, Baar K, Tipton KD. Branched chain amino acid ingestion stimulates muscle myofibrillar protein synthesis following resistance exercise in humans. Frontiers in Physiology, 8:390, 2017.
  4. Fletcher G, Eves FF, Glover EI, Robinson S, Vernooij C, Thompson JL, Wallis GA. Dietary intake is independently associated with the maximal capacity of fat oxidation during exercise. American Journal of Clinical Nutrition, 105(4):864-872, 2017.
  5. Pingitore A, Chambers ES, Hill T, Maldonado IR, Bewick G, Morrison DJ, Preston T, Wallis GA  Tedford C, Castanera Gonzalez R, Huang GC, Choudhary P, Frost G, Persaud SJ. The diet-derived short chain fatty acid propionate improves beta-cell function in humans and stimulates insulin secretion from human islets in vitro. Diabetes, Obesity & Metabolism, 19(2):257-265, 2017.
  6. Karstoft K, Wallis GA, Pedersen BK, Solomon TPJ. The effects of interval vs. continuous walking on excess post-exercise oxygen consumption and substrate oxidation in subjects with type 2 diabetes. Metabolism, 65(9):1316-1325, 2016.
  7. Macnaughton L, Wardle S, Witard O, McGlory C, Hamilton D, Jeromson S, Lawrence C, Wallis GA, Tipton KD. The response of muscle protein synthesis following whole-body resistance exercise is greater following 40g than 20g of ingested whey protein. Physiological Reports, 4:e12893, 2016.
  8. Robinson S, Chambers ES, Fletcher G, Wallis GA. Lipolytic markers, insulin and resting fat oxidation are associated with maximal fat oxidation. International Journal of Sports Medicine, 37(08):607-13, 2016.
  9. Shad B, Wallis GA, van Loon L, Thompson J. Exercise prescription for the older population: the interactions between physical activity, sedentary time, and adequate nutrition in maintaining musculoskeletal health. Maturitas, 93:78-82, 2016.
  10. Robinson SL, Hattersley J, Frost GS, Chambers ES, Wallis GA. Maximal fat oxidation during exercise is positively associated with 24-hour fat oxidation and insulin sensitivity in young, healthy men. Journal of Applied Physiology, 118(11):1415-22, 2015.
  11. Bradley H, Shaw CS, Bendtsen C, Worthington PL, Wilson OJ, Strauss JA, Wallis GA, Turner AM, Wagenmakers AJ. Visualisation and quantitation of GLUT4 translocation in human skeletal muscle following glucose ingestion and exercise. Physiological Reports, 3(5):e12375, 2015.
  12. Norton JE, Wallis GA, Spryopoulos F, Lilford PJ, Norton IT. Designing food structures for nutrition and health. Annual Review of Food Science and Technology, 5:177-95, 2014.
  13. Newell ML, Wallis GA, Galloway SD. Impact of carbohydrate nutrition on exercise metabolism and performance. Agro FOOD Industry Hi-Tech, 25(2): 32-36, 2014.
  14. Wallis GA, Wittekind A. Is there a specific role for sucrose in sports and exercise performance? International Journal of Sports Nutrition and Exercise Metabolism. 23(6):571-83, 2013.
  15. Vanhatalo A, Bailey SJ, DiMenna FJ. Blackwell JR, Wallis GA, Jones AM. Acute L-arginine supplementation does not enhance exercise efficiency or exercise tolerance in healthy adults. European Journal of Applied Physiology, 113(7):1805-19, 2013.
  16. Res PT, Groen B, Pennings B, Beelen M, Wallis GA, Gijsen AP, Senden JMG, van Loon LJC. Protein ingestion prior to sleep improves post-exercise overnight recovery. Medicine and Science in Sports and Exercise, 44(8):1560-9, 2012.
  17. Atkinson, G., Taylor CE, Morgan N, Ormond LR, Wallis GA. Pre-race dietary carbohydrate can independently influence sub-elite marathon running performance. International Journal of Sports Medicine, 32:1-7, 2011
  18. Zarins ZA, Wallis GA, Faghihnia N, Johnson ML, Fattor JA, Horning MA, Brooks GA. Effects of endurance training on cardio respiratory fitness and substrate partitioning in postmenopausal women. Metabolism, 58(9):1338-46, 2009.
  19. Zarins ZA, Johnson ML, Faghihnia N, Horning MA, Wallis GA, Fattor JA, Brooks GA. Training improves the response in glucose flux to exercise in postmenopausal women. Journal of Applied Physiology, 107(1):90-7, 2009.
  20. Hulston CJ, Wallis GA, Jeukendrup AE. Exogenous carbohydrate oxidation with glucose plus fructose intake during exercise. Medicine and Science in Sports and Exercise, 41(2):357-63, 2009.
  21. Wallis GA, Hulston CJ, Mann CH, Roper H, Tipton KD, Jeukendrup AE. Post exercise muscle glycogen synthesis with combined glucose and fructose ingestion. Medicine and Science in Sports and Exercise, 40(10):1789-94, 2008.
  22. Wallis GA, Friedlander AL, Jacobs KA, Horning MA, Fattor JA, Wolfel EE, Lopaschuk GD, Brooks GA. Substantial working muscle glycerol turnover during two-legged cycle ergometry. American Journal of Physiology, Endocrinology and Metabolism, 293(4):E950-7, 2007.
  23. Henderson GC, Horning MA, Wallis GA, Brooks GA. Pyruvate metabolism in working human skeletal muscle. American Journal of Physiology, Endocrinology and Metabolism, 292(1):E366, 2007.
  24. Wallis GA, Yeo SE, Blannin AK, Jeukendrup AE. Dose-response effects of ingested carbohydrate on exercise metabolism in women. Medicine and Science in Sports and Exercise, 39(1):131-138, 2007.
  25. Wallis GA, Dawson R, Achten J, Webber J, Jeukendrup AE. Metabolic response to carbohydrate ingestion during exercise in males and females. American Journal of Physiology, Endocrinology and Metabolism, 290(4):E708-15, 2006.
  26. Wallis GA, Rowlands DS, Shaw C, Jentjens RLPG, Jeukendrup AE. Oxidation of combined maltodextrins and fructose ingestion during prolonged exercise. Medicine and Science in Sports and Exercise, 37(3):426-432, 2005.
  27. Rowlands DS, Wallis GA, Shaw C, Jentjens RLPG, Jeukendrup, A.E. Glucose polymer molecular weight does not affect exogenous carbohydrate oxidation. Medicine and Science in Sports and Exercise, 37(9):1510-1516, 2005.
  28. Yeo SE, Jentjens RLPG, Wallis GA, Jeukendrup AE. Caffeine increases exogenous carbohydrate oxidation during prolonged exercise. Journal of Applied Physiology, 99(3):844-850, 2005.
  29. Jeukendrup AE, Wallis GA. Measurement of substrate oxidation during exercise by means of gas exchange measurements. International Journal of Sports Medicine, 26 Suppl 1:S28-37, 2005.

View all publications in research portal