The hubris (ὕβρις) is the loss of the sense of measure (phronesis, or φρόνησις – sometimes translated caution or sagacity). Le contre-la-montre (chrono) is the middle between hubris and phronesis (a quite aristotelician point of view).

In this sentence "hubris" develops on "démesure". A similar construction:

Pour mon petit-déjeuner j’ai mangé un pain au chocolat, ou chocolatine comme on dit à Bordeaux.

For my breakfast I had a pain au chocolat, also called chocolatine in Bordeaux.

The meaning of your sentence is that to be good in "chrono" (time trials), you have to be not too cautious and not too cocky. Then there is a reference to the greek word hubris that is used by philosopher to qualify this cockiness they have to avoid to be good at time trials.