Yes is the max possible based on HR for 1 hour. (technically 100 for cycling, 110 for running). Here we are using an estimated “equivalent” amount of TSS that is based around how much recovery capacity will be burned and “damage” done in this hour. (I am using damage in a positive sense here). These ME type workouts can really take a toll on folks so we use an estimates TSS of 100-150 to try and capture that amount of training stress more accurately.