Hey Christian,
Thanks for writing in – we really appreciate the participation and feedback…
I see the issue, and it’s a wording one. The 20% more time you are referring to: The plan meant to add 20% duration to the individual workouts’ planned duration based on the modality one chooses, not to week-to-week duration. So, for example, in week 1; Base workout with a planned duration of 30min, one would do 35min (..ok, technically 36min.) on trails/outdoors. Same logic goes for the base workout of week 2…week 7. The rational is outdoor tends* to be less sustained effort than indoor machines, thus a bit more duration is warranted.
Aside from the above, I reflect Scott’s comment as well – very few should be adding 20% more volume of running per week, and if so they should be very intentional about why and be able to handle that increase.
Hope this helps!
-Seth
*not always.