BRIANÇON, France — To watch the cyclists of the Tour de France assault the high Alps, those grand geologic up-thrusts of granite and limestone, to see men pedal through misting meadows and up brutal switchbacks is to thrill at feats of athleticism.

As the Tour headed toward its finale in Paris on Sunday, there were so many complex strategies and stories in the race’s final days: Would the ebullient young Julian Alaphilippe of Deceuninck Quick-Step regain the yellow jersey to become the first Frenchman to claim the title of champion in three decades? Would he fall to the high-altitude guy from Colombia, Egan Bernal of Team Ineos (the New York Yankees of cycling), or the Dutchman Steven Kruijswijk of Jumbo-Visma?

As I watched, however, another question nagged: Is all of this real?

Are these stars drawing on deep reserves within or are they helped along by a chemical new or old? When announcers exclaim that a rider pedals “like the Hulk” or describe Alaphilippe’s performance as “absolutely extraordinary,” it seems wise to temper the urge to clap unreservedly.

This sport was nearly consumed by doping. In the 1980s and 1990s and deep into this century, one champion after another fell away: Marco Pantani, Alberto Contador and Lance Armstrong, who was barred for life and stripped of seven Tour de France titles.