Sweetspot Time in Zone (one large workout vs multiple smaller workouts)

I did some quick total for the sweetspot base mid volume plans, and found that each week the total amount of time spent in sweetspot increases from roughly 110mins through to ~140 minutes

my question is, rather than complete 3 sweetspot workouts a week, would I be better/worse off completing a weeks worth of sweetspot in one session? with the remaining sessions being endurance workouts?

my sample week vs a mid volume week, both have similar time allocated to time at sweetspot

standard TR mid volume week

Short answer is that you’d be worse off.

One reason is that the work wouldn’t be equivalent - in order to do a whole weeks worth of SS in one session you’d have to be working at the lower end of SS. The plans incorporate some workouts that push the high end of SS, and in the MV and LV SS2 plans they go up to Threshold. So you’re doing less work.

Another is that every time you do a key workout where you’re pushing intensity and/or duration, it triggers physiological adaptations. Getting this hit 3-4x a week is better than getting it 1x a week.

And the last is that it’s likely not actually possible to complete. Polar Bear +1 isn’t a workout you can just jump into, you need to build up to it. Most people starting SSB don’t have the fitness to complete that workout, and if they do then assuming their FTP is set correctly then they arguably should be doing a Build plan since they clearly already have a great aerobic base.