This workout was made famous by Steve Prefontaine. The 30/40 workout is a fartlek effort used by the University of Oregon. This workout is done on the track and runners would alternate between 30 second 200m's and 40 second 200m's. We've taken that concept and adapted it to the treadmill. In this version we are doing 30 second hard efforts, followed by 40 second tempo efforts.
*From Zwift 1.49 (early October 2023), Zwift has decided to reorganize its workout library into new collections. Use More workouts like this to find identical workouts in new workout collections or training plans in Zwift. Workouts that are no longer available in Zwift can be downloaded from the official Zwift forum. See more info here: FAQ: How do I obtain and use old Zwift workouts that are no longer available in Zwift?.