came here to say this. TR focus on targeting specific physiological adaptations in the various phases of their plans. To your question about variety, with most people having an hour a day (for example) to train, it’s just not the case these random colourful mix-every-zone-into-a-workout in zwift or suffer provide better adaptations than the bog standard or specific interval structuring provided in any TR workout, unless your goal is to get a sweat up and do something random for variety’s sake. Sure, closer to the event you will want to perhaps mimic the specifics of a race, which might align closer to a SF or zwift workout, but you’re essentially getting this in a speciality plan anyway.
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