The Tour de France Femmes avec Zwift (TdFF) comprises eight stages across seven days. One of the biggest challenges riders face is fuelling the 946.3km journey, keeping pace with the expenditure of thousands of calories a day. Insufficient fuelling in a long race can spell disaster – or so cycling’s top scientists believed until very recently.
New research published in the International Journal of Sport Nutrition and Exercise Metabolism in May this year suggested that maintaining energy balance may not be as crucial as once thought, and that falling into a deficit could even improve performance. These surprise findings arose from a case study of a TdFF cyclist in the 2023 edition, which showed that despite ingesting large amounts of carbohydrate, she developed a severe energy deficit, losing 2.2kg in bodyweight over the eight-stage event. But remarkably her power output was highest in the last two stages of the race – despite the substantial deficit accrued in the days before.
