Lewis obtained a BSc (Food Science with Nutrition) from the University of Reading, followed by an MSc (Sport and Exercise Nutrition) and a PhD focusing on human water balance from Loughborough University. After two years lecturing at Nottingham Trent University, Lewis joined the School of Sport, Exercise and Health Sciences at Loughborough as Lecturer in Nutrition in 2012. He was promoted to Senior Lecturer in 2016, and Reader in Human Nutrition in 2023. Lewis is currently the Sport and Exercise Physiology and Nutrition Learning and Teaching Discipline Group Lead, and leads modules on the School’s undergraduate (Sport Nutrition) and postgraduate (Applied Nutrition) programmes.

Lewis is a keen sportsman, with a particular interest in cycling and combat sports, particularly mixed martial arts and boxing.

Lewis is broadly interested in how nutrition and exercise interact to influence human performance and health, using a variety of physiological, metabolic and behavioural methods to study questions in an integrative manner. Much of Lewis’s work focusses on the role of water, salt and carbohydrate in exercise performance/ recovery and health, with other work focussing on nutrition for performance in and adaptation to heat, and how nutrition can be used to modulate appetite and energy balance for weight management.

Current projects

  • Hydration for optimal sports performance, recovery and training adaptation in endurance and intermittent sports.
  • The role of hydration/ water balance in metabolic health (glucose regulation and kidney function).
  • Nutrition to support heat acclimation.
  • Metabolic and behavioural energy balance responses to intermittent fasting and meal skipping.
  • Carbohydrate intake for optimal performance.

PhD opportunities

If you would like to explore options for self-funded PhD topics related to the above areas, Lewis is happy to accept proposals.

Journal Editorial and Other Roles

  • Associate Editor for the International Journal of Sport Nutrition and Exercise Metabolism.
  • Editorial Board Member for Frontiers in Nutrition.
  • Invited reviewer for over 25 peer-reviewed scientific journals.

Applied/consultancy activities

  • Nutrition consultant to elite/ professional sportspersons and teams, particularly focussing on water/ electrolyte balance assessment and requirements, as well as weight management in sports.
  • Nutrition consultant to food/ nutrition industry on product design and application.

Selected Invited Talks

  • New perspectives on hydration and athlete performance (March 2019) Gatorade Sports Science Institute Expert Panel, Dallas, USA.
  • Optimising hydration for athletes (February 2019) Turkish Sports Nutrition Summit, Istanbul, Turkey.
  • The latest hydration research (October 2018) FC Barcelona 1st Nutrition Conference: Recovery nutrition for football, Barcelona, Spain.
  • Does dehydration really impair performance? (May 2018) 3rd International Congress on Hydration, Bilbao, Spain.
  • Optimising hydration practices for athletes (March 2018) EIS Tokyo Environment CPD Workshop, Bisham Abbey, UK.
  • Nutrition, exercise and appetite: hungry for more? (November 2017) BASES Symposium Session, BASES-FEPSAC Conference, Nottingham, UK.
  • Hydration: time to re-think rehydration (July 2017) Gatorade Sport Science Institute Satellite Symposium, European Congress of Sports Science, Essen, Germany.
  • Nutrition for Weight Category Sports (March 2016) Royal Society of Medicine Rio 2016 Olympic Games conference: The impact of sport and exercise nutrition, London, UK.
  • Milk as a post-exercise recovery drink (January 2015) Semex UK Dairy Conference, Glasgow, UK.
  • Effect of hypohydration on human performance (March 2014) Health impact of Modernization Conference, Jeddah, Saudi Arabia.
  • Milk and physically active individuals (March 2012) Nutritionists in industry Meeting, Twickenham, UK.


Featured publications

  • James LJ, Funnell MP, James RM, and Mears SM. Does hypohydration really impair endurance performance? Methodological considerations for interpreting hydration research. Sports medicine. In Press.
  • Carroll HA, James LJ. Hydration, Arginine Vasopressin, and Glucoregulatory Health in Humans: A Critical Perspective. Nutrients2019;28:11.
  • Funnell MP, Mears SA, Bergin-Taylor K, James LJ Blinded and unblinded hypohydration similarly impair cycling time trial performance in the heat in trained cyclists. Journal of Applied Physiology2019;126:870-879.
  • Barutcu A, Witcomb GL and James LJ. Anticipation of aerobic exercise increases planned energy intake for a post-exercise meal. Appetite. 2019;138:198-203
  • Carroll HA, Templeman I, Chen YC, Edinburgh R, Burch EK, Jewitt JT, Povey G, Robinson TD, Dooley WL, Jones R, Tsintzas K, Gallo W, Melander O, Thompson D, James LJ, Johnson L and Betts JA. The effect of acute hypohydration on glycemia in healthy adults: a randomized crossover trial. Journal of Applied Physiology2019;126:422.
  • JamesLJ, MaherT, BiddleJ, Broom DR. Eating with a smaller spoon decreases bite size, eating rate and ad-libitum food intake. British journal of Nutrition. 2018;120:830-837.
  • James LJ, Henry J, Moss J Papadopolou C and Mears SM. Hypohydration impairs exercise performance in the heat: a blinded study. Physiological Reports2017;5:e13315.
  • Evans GH, James LJ, Shirreffs SM and Maughan RJ. Restoration and maintenance of fluid balance after exercise-induced dehydration. Journal of Applied Physiology2017;122: 945-951.
  • Clayton DJ, Burrell K, Mynott G, Creese M, Skidmore N, Stensel DJand James LJ. Effect of 24 h severe energy restriction on appetite regulation and ad-libitum energy intake in lean males and females. American Journal of Clinical Nutrition2016;104: 1545-1553.
  • Dorling J, Broom DR, Burns SF, Clayton DJ, Deighton K, James LJ, King JA, Miyashita M, Thackray AE, Batterham RL and Stensel DJ. Acute and chronic effects of exercise on appetite, energy intake, and appetite-related hormones: the modulating effect of adiposity, sex, and habitual physical activity. Nutrients2018; 10:E1140.
  • MonteyneAJ, Martin A, Jackson L, Corrigan N, Stringer E, Newey J, Rumbold PLS,Stevenson EJ and James LJ.  Whey protein consumption after resistance exercise reduces subsequent energy intake. European Journal of Nutrition. 2018; 57:585-592.
  • Clayton DJ, Creese M, Skidmore N, Stensel DJ and James LJ. Effect of 24 h severe energy restriction on appetite regulation and ad-libitum energy intake in overweight and obese males. International Journal of Obesity2016;40:1662-1670.
  • Clayton DJ and James LJ. The effect of breakfast on appetite regulation, energy balance and exercise performance. Proceedings of the nutrition Society.  2016;75:319-27.