In my opinion all this depends on the workout:
Short update:
A week of TBMV1 behind me, added some Z2 workouts and have finished 5 times Fletcher as outside version pushed to my Wahoo Bolt and completed them on my Rollers Indoors, so 2:15h each at Z2.
The first of these long rides was challenging in terms of “wow, still lots of time to go”… but already the 2nd time next day was much easier.
In genereal very good feel, no tiredness the next day, I have done Fletcher 2:15h back to back twice and no problem. No need to fuel carb before or during the workout. I have just made sure I drink enough and went for 3 bottles with slight sugary drinks.
Blood sugar was great, had a huge drop after 30-45 minutes and then very stable just at my level of blood sugar comfort. And no spike after the session or during the night. My insulin need has again reduced during the week.
So, so far: very satisfied, no problem with being bored, I feel that I am doing something, but not at all do I feel exhausted, tired oder overtrained. I dont have to adjust my food or intake and I really look forward to the next session.
That’s awesome to hear! Great that it seems to work out for you so far. To remove the stress of blood sugar values not being what they should is wonderful, however one goes about it.
What you say sounds about the same as it went for me. I’m now in the last week (just added an extra week though) of mv2 and I can tell that the exhaustion and fatigue is building up, especially after the weekends with long tempo rides. But I don’t feel empty, just a bit tired which is fine I think.
I agree with your statement. Cadence work and sprints are already built into them.
Curious. Are you diabetic? I’m on my 2nd week of TBLV. I injured my right calf and badly injured my left quad back in November (was on crutches for a minute) that forced me off the bike for a minute. I did a couple of training rides (Pettit), but the quad was just not ready, so I stayed off the bike until the new year to allow more healing and the quad is still not 100% today, so I decided to start with TBLV vs SSB this time to slowly work back into things while working on my endurance and keeping my bike legs. I definitely need some distractions while doing Z2 rides indoors.
Yes, Type 1 diabetic.
Z2 sounds like the right thing for you now. I also have some entertainment during those long rides although I have switched from watching movies to listening to podcasts and audiobooks. Keeps me more focused and less stressed. I enjoy it so far.
I’m Type 2.
Update: After 10days of TB and a full week of about 11h/500tss I had to take two days off - tired and a bit of muscle soreness. Hope to get on the bike tonight again.
I have to admit that mentally I am a bit scared off the 2:37h which await me today although the intesity is absolutly fine. it is just quite long time for an indoor workout.
Looking just to stay fit and focused, have never been racing or do not plan to at all - just fitness, health and fun.
I am not sure if I will be able to do 2h plus rides on a regular basis, 4-5 times a week and I hope that even 1-1,5h rides of TB will give me some fitness and gain.
Very simple: i did the outside version of the workouts and felt fine going the extra 45min of Fletcher each time, and added one xtra Fletcher. Did feel great and not overly tired.
I actually guess that this in combination with quite some unexpected true life stress and some first strength workouts I started recently took me a step too far.
It is worth remembering that when cycling outside, the mind is engaged with the passing scenery, and watching the road for turns, traffic, avoiding debris, etc. And if you are racing, the mind is engaged with watching other riders, tactics, etc.
Replacing some of that with some other form of mental stimulation is just equalising things.
Now done with the last week of TBMV2 to which I added an extra week. I copied the last week of MV2 and added a Pettit to the Wednesday to continue the TSS progression.
I was well tired and happy that I was done on the eve of Sunday! The Saturday and Sunday 3h’ish rides in tempo (Sunday Z2) add up in fatigue. However now the last week it had some significant effect on my heart rate, from lower Z2 to upper Z3 I’m now at 5-7 bpm lower than I was 4 weeks ago. Been waiting for that effect, so was happy to see it.
Now I have a modified recovery week which I look forward to trying. The regular recovery weeks leave me flat, bloated and weak, and it takes more than a week or two to get back.
New recovery week test (65% of previous week TSS):
Shall be interesting to see how this experiment turns out.
As a further feedback with now almost finished TBMV1… i was able to do about 5-7h of TB Z2 riding per week… more I was not able to fit into my schedule with fulltime job, two small kids and a wife… also probably it would have tired me too much, see posts above.
Concerning the carbs and spikes: I did not need to fill any of these TB Z2 rides, just water, 1 bottle per hour.
And no blood sugar spikes appeared at all. That is the main positive thing: no carbs needed, no insuline shots after workout needed.
BUT: do 5-7 hours of TB have any effect at all? Does the invested time pay off? Mostly it is hard for me to motivate me for a 2hour+ ride after a long work day and family life.
So I still am torn between SS Base (1h/workout) and TB Base (2h+/workout) with all this in mind.
Congrats, those long workouts are hard to fit into a busy schedule.
I was happy with TB-1 & TB-2 MV, although my starting point was coming from off-season break. IMHO the cycling portion of the full-distance triathlon base plan is worth a look: Log In to TrainerRoad
You did not 
I feel stalked in a very positive way very good, thanks
Based on my experience at about the same amount of time I’d say yes. I had other swim/run/strength work going on at the same time, but I was also able to still do those other workouts and not be wiped out. If you can sneak in a longer ride during the weekend it will be even more useful IMO. In my current self-made plan sort of based off the Half and Full Distance Triathlon base plans I’ve been alternating a long Z2 ride (building 15’ each time) and a 90’ Phoenix Tempo ride on the weekend to mix things up a bit more and only have to endure the long trainer ride every 2 weeks. 
For me TB2 MV (With an extra week tucked on) resulted in a 15W increase in FTP, whereas SSB havn’t netted me any gains. This is individual as most things I guess, but looking at what I gained from TB so far:
I would say that for me, it has payed off. And now I am looking forward to doing build that will of course be rough, but I’m feeling … fit.
Definite win. From early October I did 9 weeks based off TBHV 2&3, phasing in a few SST workouts in the 2nd half. I also added longer Sunday rides, working up to 4.5 hours. I think the benefit was just from more time in the saddle pushing the pedals. I got a high of 879TSS, which would destroy me if done as higher intensity workouts.
I’ll definitely do another base period like this in future. Might even stick a few more weeks on next time
That’s a lot of TSS even for TB. Can i look to your workout list? I’m currently doing modified TBHV 3. I’m swapping the SS kind of workout with some threshold or Vo2max workout and hovering around 690 to 700ish TSS.
My calendar should be visible. I did a couple of SST workouts the last weeks, which will have bumped it a bit
I’m having a tough time with the longer workouts too. I have no excuses as I have a flexible job that allows for enough time to train 10 hours or more. My limiter is my aerobic fitness and my lack of durability. I think even low volume hours at z2 has a positive effect assuming it’s a different stimulus than you’ve previously attempted.
I’m not only tracking FTP but efficiency and HR decoupling (even with short-for-endurance 1.5 hour rides). I’m tracking fatigue and being honest with how much volume I can handle every week being very careful not to extend hours too quickly.
My hope with my first ever experience with a true base phase is improved durability, less fatigue in later phases, and better aerobic and muscular endurance. I’m a bit surprised at how fatigued I feel today though after 4 hours of TR endurance work and one spicy 2.25 hour group ride during this week. I need to weigh the cost benefits of my weekly group ride as it’s never a slow roll.