It’s really hard to see noticeable improvements from volume alone unless the volume is an increase in training load. I’ve been relistening to a few past episodes of that triathlon show, notably the ones that are related to the Jan Olbrecht/Sebastian Weber/Dan Lorang coaching philosophies. You can see how the ideas of using VO2 max and VLamax to guide your training.
Polarized training mainly focuses on raising VO2 max, Sweet spot training mainly focuses on raising fractional utilization of VO2 max. Once you get to a certain level of fitness, you can’t improve both at the same time. Judging by my baseline levels, I can still see some decent improvements in fractional utilization so I’m not going to throw out the sweetspot tool. I think what gets challenging is trying to balance doing SS + VO2 efforts as they have competing priorities, yet SSB2 is usually a very effective plan. How much intensity is enough, as the goal is to only do just the minimum it takes to get the desired adaptation. From listening to some other higher level coaches, when doing sub-maximal efforts as intensity, you definitely can spend a higher percentage of your time doing some quality work.
I’m probably going to do some alternating blocks this fall/winter SS1 to Polarized/VO2, SSB2, race build/specialty. Each goal block with be 2x(3hard +1 recovery) until race prep.