Here’s a question for ya: Is it necessary or desirable to do back-to-back training days if you are training for a one-day event?

I’m asking for myself, obviously, but also for someone I’m trying to help get ready for the Etape du Tour. In the past I’ve nearly always done multiple days of training in my program, but this year I’ve planned it so that I’m usually doing a lot of volume each day and then have time to recover before the next ride day. To me this makes sense as long as the volume and necessary intensity is in the program, i.e. the training mimics the event, more or less.

I guess what I’d like to know is if there is a specific physiological benefit (for a one day event) by doing two or more days in a row?

Teach me!