3 reps of 20 and 40 second sprints and 2 times a 1 minute all out effort to finish it off. Don’t go all out but save some energy to make sure you make it to the finish. Especially the 1 minute intervals should feel really hard.
Explore this cycling workout
Try the JOIN cycling app to export the workout to Zwift, Garmin, TrainingPeaks and Wahoo.