Insights into the dietary intake of world-tour female cyclists have been scarce, until a study revealed the energy demands and nutritional strategies of a woman participating in the 2023 Tour de France Femmes.

The study published in Human Kinetics Journal notes that despite an 80% increase in female athletes registered with the Union Cycliste Internationale between 2012 and 2020, there is little information on the way they fuel during top-level competition. 

The Athlete and the Event

The athlete in the study was a 29-year-old professional cyclist classified as an all-rounder and an individual time-trial specialist. At the time of the race, she weighed 71.5 kg (157 pounds) with a body fat percentage of 20.8%. Despite reporting oligomenorrhea and clinically low triiodothyronine levels, she was otherwise healthy and fully prepared for the race.

The 2023 Tour de France Femmes covered 956 kilometers over eight stages, each varying in distance and elevation gain. The cyclist’s role was primarily to support a teammate with a strong chance of winning the general classification while also striving for her best individual performance, particularly in the final time-trial stage, the research notes.

Nutritional Strategies and Energy Demands

The study points out that he Tour de France Femmes is not just a test of physical endurance but also a challenge of maintaining energy balance. Road cycling demands high energy expenditure, and for male athletes, the total daily energy expenditure during such multiday events has been reported to be 3.9 to 5.3 times the resting metabolic rate. However, there is a significant lack of data for female athletes, making it difficult to develop tailored nutritional strategies that address their specific needs.

For the female cyclist in this test, the average daily energy expenditure during the race was 7,572 kcal/day. However, the average daily energy intake across the first seven stages was 5,246 kcal, indicating a significant energy deficit of 2,326 kcal/day, according to the research. This deficit is critical, as prolonged low energy availability can have negative effects on performance, recovery, and overall health, particularly in female athletes, the study said.

Daily Diet Breakdown

The cyclist’s daily intake included an average of 13.7 g/kg of carbohydrates, 2.4 g/kg of protein, and 15% of energy derived from fat. Carbohydrates played a big role in fueling her performance, with an average daily intake of 973 grams accounting for 72% of her total energy intake. Protein and fat intake were more moderate, reflecting the need for sustained energy and muscle repair without overburdening the digestive system, the study noted.

Her protein intake, which is crucial for muscle recovery, remained relatively consistent, averaging 171 grams per day.

Hydration and Body Mass

Despite the intense conditions, the cyclist’s hydration levels remained relatively stable throughout the race, with minor fluctuations that did not significantly impact her performance, the study said.

Over the course of the race, the cyclist’s body mass decreased from 71.2 kg to 69 kg. This weight loss, while expected in such an intense event, highlights the challenge of maintaining energy balance in multiday races, according to the study.

Implications and Future Directions

This case study provides valuable insights into the energy demands and dietary strategies of a world-tour female cyclist, the researchers concluded. 

The significant energy deficit suggests that female athletes in similar events may be at risk of under-fueling, which can have detrimental effects on performance, recovery, and long-term health, the researchers wrote. This underlines the importance of developing sex-specific nutritional guidelines for female endurance athletes, particularly in high-intensity, multiday events like the Tour de France Femmes, according to the study. 

Future research should focus on expanding the understanding of TDEE and energy requirements in female athletes, with an emphasis on developing personalized nutrition plans that optimize performance while safeguarding health, the researchers said. By closing the gap in sports nutrition research for women, they noted, there will be better support to help female athletes achieve their full potential on the world stage.

Photo: A.S.O./Charly Lopez