Question on JuliAnne's early season recommendations

Let me start by stating that I am a novice - just starting my second season of triathlons.

Based on JulieAnne’s early season training advice, I’m trying to hit a cadence of 90 RPM during my rides(riding a trainer).

Here’s my question - When I’m concentrating on “scraping the mud off”, to keep my HR at the proper level requires either 1) 100+ RPM in one gear, or 2) Shifting to the next gear with a cadence of <= 80.

Which is the better way to go?

Thanks!!

Consider getting a rear cassette with closer-spaced gearing or a trainer with variable resistance.

That doesn’t sound right, no road cassette has gaps like that. What are the two gears that you are switching between?