Mis-timed intervals on the road

What does everyone do when you mis-time an interval outside? For example, the other day I was doing 3min VO2 intervals with 3 min of rest in-between. It was on a route that I only ride occasionally so I don’t know the turns, hills etc by heart. I few times I was in the middle of an interval, say 2 minutes in, and I came up to a corner that I had to slow significantly for. That obviously blew up my average power for the interval, but what I would do would be to add on ~20sec to the end of the interval. Similarly, there were times it was time to start an interval and I was on a good downhill so I would get an extended rest, also sub-optimal. If there was enough ‘extra rest’ during a block, I’d add an interval.

Anyone with other ideas how to handle these situations?

Don’t worry about it too much. It’s not going to be a disaster. If I’m doing intervals on the road, and I know that I’m not going to have enough time to complete the interval with minimal disruption I will either start it late and carry on with the session, or accept that there was a part of it that didn’t meet the target power…

However if I’m going to do a structured session, I’ll plan the route around the session. If I’m riding roads I don’t know, I’ll often just enjoy the ride. Maybe go hard on a few hills, sprint for a few town signs etc. Kind of like the Fartlek sessions of old.

Just drag your brakes and keep pedaling at your power as best you can.

Use the corners as race simulations. Keeping it safe of course, I take the corner as close to race like as I can under the circumstances and focus on staying on the power as long as I can and then getting back on my target power quickly.

On down hill sections, its good practice to try and hold the power target unless you’re truly spinning out of your top gear.