Hi @jazzwolfcx - generally the beginning of all gravel races are very hard. You have the pros up front and the rest of us behind trying to hang on.
Most gravel race power files begin with VO2 and supra threshold power that fades into threshold that fades into sweet spot that fades & so forth. Its a slooooow burnout.
Also sometimes the course features terrain that involves a climb (Crusher in the Tushar for example) that contributes to that first hour being crazy hard.
Therefore what we are recommending in this workout is for you to get creative with the terrain/rides you have and go HARD for 1 hour to simulate the beginning of YOUR gravel race. Customize it for what you are training for.
Then the catch is - you do not get to stop and take a break after that hard one hour - you have to KEEP Going (!) just like a gravel race.
270 TSS For a 4 hour ride is representative of what you will do in a Gravel Race (but less so as most gravel races >400). Remember this is a SIMULATION. This is not an easy workout. 270/4 hours = 67.5 TSS/hour >> use TSS displayed in real time on your bike computer to help you stay on the gas during the workout and budget out your energy.
That is a .82 IF so it’s high tempo which is easy for a 20 minute interval but for 4 hours - really really hard.
We are challenging you for sure! “Practice how you want to play” - this is how.