MEN:

50-40-30-20-10 Cal Airbike
10-20-30-40-50 Cal Ski Erg

30 DU after every set (10x30 DU total)

WOMEN:

45--35-25-15-5 Cal Air Bike
5-15-25-35-45 Cal Ski Erg

30 DU after every set (10x30 DU total)

RPE 3-4

If you don´t have Ski erg, scale to rowing or running.