Alpe d’Huez is already just a memory, and not the best for the most prominent French people this year. At the arrival of the mythical 21 laces, David Gaudu complained of having lost 54 seconds on the yellow jersey Jonas Vingegaard: “It was tough in this heat. I didn’t have confidence in myself, I was afraid of exploding. » Romain Bardet let go of barely 19 seconds, the lesser evil, the fault again with the bad sun: “I had a heat stroke, I started running out of water and getting chills. »
The thermometer showed 35°C at the foot of the famous climb. It’s a lot, but it’s only a taste of what awaits the peloton this weekend in Occitania where the heat wave has already been raging for a few days. Saturday, 36 ° C are announced in Mende (Lozère), and the mercury should approach 40 ° C near Carcassonne this Sunday. A time not to put a runner out?
“Cycling is not the most risky sport”
“It’s not insurmountable. assures Xavier Bigard, the medical director of the International Cycling Union. The main thing is to leave with the optimal level of hydration, and therefore to have properly restored the fluid losses of the day before. To evaluate them, just weigh yourself before and after the stage. If the loss is two kilos, it is necessary to drink three liters. We must insist on this. Then, during the warm-up and the wait before the stage, care must be taken to maintain a fairly low body temperature, and vests equipped with ice packs allow this. Finally, during the race, you have to think carefully about your regular fluid intake strategy. »
The organization of the race and the regulations on refueling can then intervene. The latter, normally prohibited during the first and last kilometers of a stage, can be reinstated in the event of a heat wave. On the Grand Tours, “neutral” water-carrying motorcycles can shuttle between the different groups dispersed on the route. It is also up to the teams to position their supply assistants well. Finally, at worst, a decision may be made to shorten the stage or to shift its schedule.
“There are two types of heat injury, explains Xavier Bigard. The first is spectacular, but commonplace: heat syncope, linked to the fact that the athlete has lost too much water. The second is more serious: exercise heat stroke, a neurological accident that must be treated as quickly as possible, by lowering the body temperature. But cycling is not the most risky sport in this regard. Because when you ride, the wind still helps to dissipate the heat. »
Real differences between runners
Responsible for the performance of the Cofidis team, Samuel Bellenoue also minimizes for his part: “You shouldn’t worry too much and focus on the Tour de France. Throughout the season, we sometimes run in temperatures above 40°C, in Argentina or Australia, for example. We know how to adapt. To cool the organisms, the riders are equipped with ice socks to slip into the jersey below the neck, which gives them that dromedary look. We renew them as often as possible, except when the stage is very lively of course. »
If, when the attacks are coming from everywhere, the champion does not take the time to properly rehydrate or misses a supply, he can pay for it very quickly. “The loss of 1 to 2% of body weight in fluid can translate into a 10% loss in physical performance, details Samuel Bellenoue. The rise in body temperature also induces a lower performance, but some individuals tolerate it better than others. »
And this is the major difficulty for the doctors or the supervision of the runners. “If there is one constant in humans, it is the variability of responses to physical stress, emphasizes Xavier Bigard. The difference for example in the sweat rate can range from 1 to 3 depending on the runners. They also do not all react the same to the decrease in blood flow induced by dehydration. » Tadej Pogacar would not be very comfortable on overheated roads. Neither does Romain Bardet.
Some runners actually work to confront the heat more often through sauna sessions, training courses in hot countries “where you can train more often, three or four times a week, at over 35°C”, says Samuel Bellenoue. The peloton hopes, however, that the conditions will be less extreme in the middle of next week for the most severe stages in the Pyrenees. There will then be no need for the star to act up, because, between the big names, it will heat up.
