Considered the most gruelling of all cycling races, the 112th edition of the Tour de France got underway July 5. The 21-stage race spans four mountain ranges (Alps, Massif Central, Jura and Pyrenees), with the cyclists traversing 3,320 kilometres by the time they sprint to the finish line along the Champs-Élysées in Paris on July 27.

The cyclists competing in the Tour have long been touted as some of the fittest athletes in the world, exhibiting high levels of endurance, speed and power over the course of the three-week tour, of which there are only two rest days. But it’s not just the distance that makes the Tour so tough. The time-trial stages demand riders sustain high levels of speed, and the hilly segments — some of which end with a climb ranging anywhere from five to 20 km in length — require the rare combination of power and endurance.

It’s these kind of extreme physical demands that has made the Tour a great opportunity to test the limits of human performance, with several studies dedicated to outlining the unique physiology of a Tour de France cyclist. But to really drive home the level of fitness on display by the cycling elite, researchers have documented the physical demands of the Tour de France on recreational cyclists and compared the........

© Montreal Gazette