Thank you to everyone who joined our recent webinar with Prof. James Morton, Dr. David Dunne, Dr. Samuel Impey, and Bob Jungels. It was fantastic to see such an enthusiastic turnout and engagement. The session was packed with valuable insights into the nutrition strategies that fuel Tour de France champions.
We received an overwhelming number of great questions during the webinar. While we tried to address as many as possible, we ran out of time to answer all of them. But don’t worry—we’ve compiled a list of those unanswered questions and provided detailed responses below. So let's get into it!
What is the substances/ingredients in the bottles handed to TdF cyclists upon finishing the stages?
The most common ingredient is carbohydrates as the riders bodies are most like a sponge for the first few hours after the stage and this is the best opportunity to refill the tank. As Bob mentioned on the webinar, after some carbs rides will often have protein and some use ketones. Dr Sam Impey
I wanted to know how well the altitude exposure camp works so far in advance of critical events, surely the physiological changes diminish quite rapidly on return to ’normal’ altitude. In my own experience, noticeable benefits diminish quite rapidly and are not materially evident after about four weeks - perhaps marginal gains last much longer?
Great question! It is generally thought that there is a dip in performance of 5 - 10 days after returning to “normal” altitude before peak performance is seen. But its important to remember that TdF riders will do multiple altitude camps in preparation and so get a compounding effect. Dr Sam Impey
How many ounces of fluids does an average TdF cyclist consume?
We can easily have over 200 fluid ounces throughout the day during a hot stage. Bob Jungels
How does a rider calculate how much carbs to intake per hour? Is it calculated from body weight?
The carb intake requirement can vary based on the session type, intensity and duration. Tools such as Hexis can now turn this workout data into personalised fuel plans for each individual. Dr David Dunne
How do we make sure to be able to ingest 120g carbs/hr on race day? What is the process to accommodate it?
TdF riders will often do 20+ hours per week training, so they have a lot of accumulated experience of fuelling. They will plan specific training rides where they want to train their gut and test race fuelling - these can often be when doing a recon of a stage several weeks before the tour. We wrote an article on how recreational athletes can train their gut that you can find here. Dr Sam Impey
How does the data compare between male/female athletes? With females having a higher body fat %, does this impact CHO requirements and the cho/fat crossover rates?
Really interesting question! Females generally have lower total carbohydrate requirements for racing, this is because the length of stages are shorter and the number of hours they are racing for is often less than that seen in mens races. van Erp and colleagues published a paper looking at 4 years of data to outline the training and racing characteristics of male and female professional riders https://pubmed.ncbi.nlm.nih.gov/31722298/ - One interesting observation from the research, based on heart rate, it appeared that females trained at a higher intensity and so potentially need a greater percentage of carbohydrates in the diet. Dr Sam Impey
For those higher CHO intake stages where we are seeing the intake in the high teens 18g/kg etc. How long does it typically take the athlete to train that kind of intake?
To get to a daily total carbohydrate intake of 16 - 18g per kg takes years! Its important to remember that the riders will be getting 55 - 60% of their total daily carbohydrate intake on the bike during the stage. Dr David Dunne
Sometimes, in race, it is difficult to keep track of your intake. How late is too late? And how early is too early? Can taking 150gr/h early in a race, when not going as hard, still help you later in a race when maybe you only manage to take 60gr/hr during a climb?
It is always better to start feeding early and for as long as you can manage. Feed more at the start of the race if you know you can not ingest as much on climbs. Dr David Dunne
Do you carbohydrate load on the day you have heavy training or a race? Or a day prior to?
You would load the day before and at breakfast for a race. If you had a hard training session you could have a high carbohydrate meal the night before and then a high carbohydrate breakfast on the morning of training - but this depends how long/hard your training session is. Hexis can help you with planning this fuelling as it works over a 3 day period. Dr David Dunne
Would you trial train low with ultra trail runner recreational athletes? Thinking more so from an injury perspective
You can apply train low as part of a structured training block and likely as part of lower volume days, its important to plan train low sessions with the coach and have a clear rationale for what performance element you are trying to achieve. It's good to think about how train low sessions fit into a meso and macro training programme. Dr Sam Impey
Do we have some numbers with regards to the increase of CH usage in colder environments?
Interesting question - research suggests that exogenous oxidation of carbohydrates (from gels, drinks, bars etc.) is not altered by exercise in the cold. Whole body carbohydrate oxidation is likely to be affected by the cold, but still by far the biggest effect on fuel use will come from the intensity of exercise! Dr David Dunne
How do you periodise carbohydrate intake without creating a LEA that risks athlete health? I support elite ultra runners who are training up to 20 hrs per week.
See the answer above about how to structure train low into the training programme - it's important to recover very well from train low sessions, especially if the athlete is undertaking a large training volume. Dr Sam Impey
Is there any research on nutrition periodisation with junior athletes?
There isn’t any research on junior athletes as at that stage in an athletes journey they should be focusing on food knowledge and basic cooking skills, developing a healthy relationship with food and understanding how it helps support their training and performance. Prof. James Morton
I’ve heard that, if an athlete has muscle damage, he cannot store glycogen correctly. Could a tough Grand Tour stage lead to such muscle damage?
You are correct that muscle damage can impair muscle glycogen resynthesis - this could be a factor in the last days of a grand tour as a result of the accumulated fatigue, but the difference would only be small. Where research has seen impaired resynthesis has been following heavy weight training and marathon running, both of which produce a much greater damaging effect on the muscle. Dr Sam Impey
How are you balancing the CHO restricted training with training the digestive system to handle the high CHO intake necessary for competition?
The riders will have days in a training block that will have a train low focus, this is generally done as part of the preparation phase of training. Then as the intensity of training increases riders will add in gut training sessions that focus on replicating how they want to fuel in the race. Prof. James Morton
Regarding the strategies of sleeping low and training twice, how many times per week is it recommended to include them to achieve molecular adaptation and impact mitochondrial biogenesis when athletes are in general training period?
Observational studies from some of the best endurance athletes in the world have reported that train low sessions can be used 2 - 3 times per week at the start of a training block and are phased out as training intensity increases. Prof. James Morton
Could you comment on how relevant you think low carbohydrate training is for women? Given the limited research on women and impact of low fuel availability on the incidence of REDS?
It's a really interesting question that often divides opinion. From my research and applied experience I think that train low strategies can be used very effectively by female athletes when planned as part of a structured training goal. It is important to have a clear rationale for why they are using train low and how it fits into improving their performance. To avoid the risk of low energy availability it is important to recover effectively and fuel well throughout the other training sessions. Prof. James Morton
Does the amount of carbohydrates consumed differ between the period of preparation for competition and during competition?
Yes, during competition you should be consuming more carbohydrates to support the intensity of exercise. Dr Sam Impey
Do you perform carbohydrate periodisation to achieve better adaptation to the metabolic system?
Yes, this is one component of the potential benefits of carbohydrate periodisation. We wrote an article about how you can alter your fuel use with carbohydrate periodisation that you can find here. Dr Sam Impey
Weight management during the Tour: What would be the maximum energy deficit that you aim for per day and do you achieve it only through carbohydrate periodisation or a reduction in fat intake as well?
To ensure optimal performance riders would not try to reduce body mass during the tour. They (should) will arrive at race mass having made any adjustments to body composition in the weeks leading up to the race. An energy deficit can compensate the recovery process and is a risk to performance, so we try to avoid it during racing. Dr David Dunne
Why don't you use the rest day’s to upload more CHO? Why , only“ 3g/kg?
The riders will have almost completely refilled their stores of glycogen in the 8 - 12hr after the previous stage, so we are just looking to support any training that occurs on the rest day, and top up the liver glycogen ready for the following stage. The range would be 3 - 5 g/kg of carbs for a rest day. Dr Sam Impey
Can you discuss the hydration protocols, in addition to the CHO drinks?
We are recommended to drink to thirst, but always try to take regular sips of a bottle with carbohydrates, water or electrolytes in. Bob Jungels
Within a stage how is CHO ingestion structured? Is this based of expenditure associated with phases of a stage?
You would try to keep the carbohydrate intake similar for each hour of racing, this is both practical and easy for a rider to follow. Dr David Dunne
%2520(1).webp)
.webp)
