This year’s Tour de France is taking place under the strong threat of the covid-19 disease. It all started at the preparatory race of the Tour de Suisse, where half of the peloton withdrew due to an infection. Stables have been making last-minute line-up changes and 13 riders have tested positive since the start of the Tour in Copenhagen, including stage winners, team leaders and vital domestics.
Cyclingtips has now detailed the struggles of Danish rider Magnus Cort (EF Education-EasyPost), one of the key players in the early stages of the race. After the Tour started, Magnus Cort literally flew. He spent more than 500 km in the escapes, rode most of the first week in the dotted jersey of the best mountaineer and rounded off his great ride with a victory in Tuesday’s 10th stage.
But then he started to get worse.
I was lethargic and had several other symptoms. It wasn’t a fever, but it was like several of those symptoms overlapped with fatigue.
As the cycling website writes, there is a surprisingly complete picture of Cort’s changing condition. Both from his reported impressions and in the form of data released from his “smart” Whoop bracelet.
Cort wrote on Saturday 7/16 that he felt discomfort since Wednesday 7/13. But at that moment he still had several negative tests for covid. “I was lethargic and had several other symptoms. It wasn’t a fever, but it was as if several of those symptoms overlapped with fatigue.” The Dane also began to have trouble falling asleep. We know he was up late the night after his stage win, but the celebration from that night turned into insomnia after that. “Fatigue settled in my head. I feel used. It is mentally difficult to ride such a long bike race. Especially in this crazy heat,” he wrote in his notes.
Then on Sunday morning 7/17, Cort got an answer to why he felt so bad. He tested positive after five days of symptoms. “Magnus Cort woke up this morning with a headache and fever and has since tested positive for covid-19. He will not start in the 15th stage of the Tour de France. Medical examinations are ongoing,” his team said on social media.
What Czech sports doctor Karel Martinek says
In today’s age of modern technology, we see how these “gadgets” like the Whoop bracelet can positively influence the training process of athletes. The tiny bracelet is packed with practically everything, from sleep monitoring to e.g. monitoring regeneration time or blood oxygenation. It’s an all-in-one bracelet.
The author of the article describes the body’s reaction to physical stress during the period of health and incipient covid disease, when Magnus Cort was not yet positive, but was already in the early stages of the disease. I think it is not at all surprising how the deteriorating subjective condition of the cyclist corresponds with the data from the race in the period before the illness and in the illness from the bracelet day after day. 20 or more years ago, athletes mostly only followed their morning heart rate and went with their feelings. On the other hand, it must be said that they knew their bodies much better. Today, the aforementioned modern technologies do it for them, which are mainly monitored by their coaches or doctors for a long time and use the information for effective training and eventual treatment more than the athlete himself.
On Monday, Whoop, a company that makes “smart” bracelets for monitoring heart rate, temperature and other indicators (it is one of the sponsors of EF Education-EasyPost), decided to share the physiological data that supported the impressions observed by Corte.
For example, looking at Cort’s recovery rate – how quickly he got rid of fatigue from day to day – is very significant. During the early days of the Tour, Cort’s day-to-day recovery averaged 57%. On the day of his positive test, Sunday 7/17, it dropped dramatically to 19%.
His breathing rate also increased significantly – from 14.5 average breaths per minute to 16.5.
His resting heart rate showed an even more dramatic increase. During the five days leading up to the positive covid test, his resting heart rate slowly increased from 37 beats per minute (extreme endurance athletes actually have a resting heart rate that low in the morning after waking up, basically half that of the normal population, ed.) down to 47 beats on the day he retired from the race.
Accordingly, his heart rate variability also decreased. This rate of interaction between the parasympathetic and sympathetic nervous systems, measured in milliseconds, is an important indicator of the body’s health, according to Whoop. A low level indicates that the human body is working hard for some other reason (perhaps it is tired, dehydrated, stressed, or sick and needs to recover). This then leaves less resources that the rider absolutely needs to complete the race.
In the 11th stage, Cort’s smart bracelet showed a value of 99 ms. At stage 14, as his body began to fight the growing infection, the value dropped to 87ms. And on the day of the 15th stage, 7/17, when he had a positive test, there was a dramatic drop to 61ms.
The last metric shared from the smart bracelet was related to fever symptoms.
As the Dane faltered in performance, his temperature began to rise, eventually up to 2.0°C.
And then came the aforementioned withdrawal from the race.
