Everyone is different but I have found that it works well to “bargain” or “trick” myself into starting a workout.
It basically goes like this:
“Ok, I’m gonna put my bibs on but I don’t have to workout”
“Alright, well as long as I have my bibs on I might as well ride for a few minutes. How about just 5 minutes and then I’m done?”
“Might as well do a little warm up now too”
“I’ll start this first interval and see how it feels. Maybe I’ll bail early if I don’t feel good”
“That wasn’t so bad! Bet I can beat my power on this one.”
By that point you’re well into the workout 