I’ve seen a few similar posts to this but most people ask about swapping a 2 hour SS ride for a longer outdoor z2 ride.
My question is about a progressively longer tempo ride. As I’m aiming to peak in June for a 100m TT — where I’ll spend 4 hours in the middle of the tempo zone (82%ish). Are there any downsides to swapping the Sunday ride for a long race-power tempo ride provided the TSS is about the same?
Only downside will be building too much fatigue that means you cant complete the weekday sessions with quality. If you can cope with it without issues then go for it, but remember the fatigue really builds over weeks, especially on HV plans, so might be better to start easy and only add if you can definitely deal with it.
Whilst I agree with the sentiment, I don’t understand why replacing a 120 TSS ride with 90’ of SS with a 120 TSS ride with 90’ of tempo be more fatiguing?
A ride at 82% builds up TSS at roughly 83% of the rate of a ride at 90%. So up to 2.5 hours at 82% would be about the same stress as a 2 hour ride at sweetspot.
I would say it’s fine…but not every week…maybe have one tempo/one 2hr SS/ one longer zone 2 on a rota?
Makes sense. Thanks 
It would be weather dependent, so I imagine there will be a few inside & a few Sunday’s where I’m feeling tired so a long z2 pootle will be ideal
I wouldn’t do this now if your race is in June. You want to focus on getting your ftp as high as you can and true tempo rides aren’t efficient at doing that. As you get closer to your event then look at doing this.