I’ve done my learning doing running plans for a number of years, and the entry into a program is not something that’s one-size-fits-all, since we all come from different places. Some programs have an entry sequence, so-to-speak, that’s low-volume, low-intensity, to get you going if starting from a lower fitness level; this is a lot more important in running than cycling, as you need to stimulate and develop the articulations in preparation for the volume coming ahead. This said, I’ve only done TR low volume plans so far, and I think SSBLV1 is a pretty good entry door. LV2 cranks things up significantly, and some riders may benefit from stretching Base 1 and/or the beginning of Base 2.