I’ve been wondering what’s the consensus here about outdoor long rides (2hrs and over) instead of the 2hr TR rides…
I love TR for intervals and sweet spot rides. But for longer slightly easier efforts, riding out seems to be the best choice (at least mentally)
This weekend I have a 2hr ride and was planning to turned it into a 2.5 hour ride (plus the 30 minutes brick run afterwards)…
Anyway… TIA
I guess it depends on where in the world you are and what your local government is recommending in terms of exercise in the pandemic…
For me weather is the determining base factor. If its nice then I’ll go outside, if not, well no choice but to grind away indoors 
When indoors though I’ve managed to learn to cope with the monotony of the ride. Podcasts, zwift rider etc. are making the longer indoor rides manageable.
2 hours inside seems to be the best bang for buck, your done and dont have to worry about stop signs or traffic messing up your intervals. Less time getting dressed and leaves more time for family. Or that is my reasoning
I’ve been watching movies. I don’t tend to watch them much otherwise. Never thought I would ever do two hours on rollers when I first got them and it has taken TR for me to be able to do it!
I have done 6 hour rides on the trainer and 6 hour rides outdoors. Outdoors is more pleasant but indoors definitely has some advantages.
1.) You’re never far from a toilet.
2.) You’re never far from a 'fridge.
3.) It’s not impossible that a car might crash into the room and run you over but I’ve never heard of somebody getting killed by a vehicle while on their trainer indoors.
4.) A flat tire doesn’t stop your ride.
5.) No stop lights.
6.) No rain.
7.) Doesn’t matter if you didn’t put on sunscreen
I could go on. Of course, there is a similarly long list of reasons to ride outdoors. But #3 sticks in my mind recently…risk of death is just so much less riding indoors.
Still, I’m a big proponent of doing the occasional shakedown ride outdoors. There are just some things you can only find out on a long ride outside. Mechanical things…mental things…nutritional things…
So, get out there and do a long ride every so often, but be safe. So ends my bloviating on this topic. For now.
I agree, best bang for buck inside. 2 hours inside is not fun on my butt though, especially consecutive longer days - outdoors it never seems a problem.
If the weather good, Get outside. Try to match the ride to what you were going to do on trainerroad. If its miserable or lock down does not allow you far from home. Stick to the structure ride. I have trained 5 days a week for the last 5 1/2 months. with the odd 50 mile outdoor ride once a week and have had a 60 watt increase in FTP. I take 2 days a week off to recover and this works for me.
I usually add some extra time to outdoor rides to try and offset traffic lights and the like. The TSS is higher but I don’t think TSS takes the extra rest into account.
On a nice day I’m not always able to control how far I go. It may be detrimental to training the next day, but it sure is good for the mind.
As I do not earn my bread with cycling I would always pick outside rides above indoor. In my view, an amateur should generally not pick indoor training above an outdoor ride (assuming weather conditions etc are okay and of course there can be some specific reasons to ride inside).
I’m a 2 hour indoor guy. All z2. Especially in light of the epidemic.
I find that such rides can be “boring” but thats kinda what its supposed to be no? I throw on some movie and just get my workout in. Its incredibly convenient for me this way.
Outdoors is nice too. Can’t speak of which one is “better”. I just think as long as you put in the work, you’ll be fine.
If possible, I’ll always do my riding outside, even the interval work. Luckily i have a lot of nice places to ride, a lot of different routes nearby, so i don’t have to do the same round each time (i often do though, got some favourite stretches of road). I also am lucky enough that there is plenty of good hills and flats to do both vo2max and ftp/ss-work without much hindrance.
If the weather is fine and it is safe to do so (COVID), I’m heading outside. I didn’t buy a bike(s) to ride them on a turbo in my garage.
Plus, I don’t race on ZWIFT so I do believe that being able to ride in the rain, wind or whatever the weather might be, is going to serve me better come race day.
For aerobic longer than 1.5 hours I am definitely going outside if the weather allows me to (and I’ll put up with a decent amount of rain or wind before I head inside). Not only is this the easiest type of riding to do outside but it also is just plain enjoyable. The mental refresh is almost more worth it to me than the workout.
If the weather is too good not to be outside and I’m allowed, I’ll ride outside for a 2+ hr effort unless I’m testing nutrition because…toilet
Though for 1hr Z2 or recover rides, I like to do those outside if the weather is crappy. Reasoning is that if I’m heading inside when the weather is bad for the long ones, I should at least have an idea what nasty weather feels like and how to deal with it on the short rides.
I think it’s about finding the right balance and, right now, following your local stay safe guidelines. For some people that balance may be exclusively indoors, outdoors, or some combo of the two. I’ve been doing most of my training indoors since MidSouth but yesterday was just too nice out so I took the mountain bike out for a long 4 hour ride to two different local trails.
I’ve done I think up to around 3-4 hours on the trainer using either Zwift exclusively to tackle the longer pre-set routes or with a combo of TR for some structure and Zwift for some freeriding/endurance miles afterwards.
You could also use the outdoor version of the TR workout and just add to it if it isn’t long enough.
Weather has been good in the UK recently so I have been out a lot - it will be less in winter and when I actually have to go into work again. That said 2 hours - endurance/ss is a long trainer ride. 2 hours outside isn’t ….so if its winter or the weathers crap then 2 hours ss or harder endurance @70-90 %FTP is good. If the weather is good 3-5 hours outside @60-70%FTP is good. Outside you don’t have to work as hard if you are out for longer. But they are not the same type of ride so it depends what you want - all things being equal get outside when you can unless you are doing intervals or the weather or lack of light stops you.
I’ll always ride outdoors* where I can - especially on the longer more aerobic rides.
*Weather permitting - UK weather is very changeable.
Thanks for all the inputs…
It seems than consensus is: there is not a consensus! 
In any case…
Safety is a huge consideration for me (and one of the reasons i wanted a smart indoor trainer). Im fortunate that i live in an area where cycling is OK. Not super safe, but i can get to safe areas quickly enough.
Social is also very important. When i ride out, i try to go with a friend. We are very close in fitness so we share the road. Its a nice fun thing to do and its different than all the series watching ive been doing while on the trainer.
The other consideration is that i can ride longer on the road. I am aware the trainer is by far more efficient, and than the best use of my time would be on the trainer.
But there is something special (mentally) when you do a 50 mile ride outdoor. I live near the the ocean in Florida, and i ride on a road with a view of the water. In the morning is very calming and relaxing.
So i guess my take away is: If i my friend can go, then Ill ride out this weekend. If he can’t then ill wake up little later and ride indoor.
Tues/Wed/Thurs “quality” sessions are almost always inside regardless of weather. Anything over 2 hours is outside if the weather is reasonable. Outside always includes some junk miles, but I can mix in some structured work and it’s really the only sane way to get those big TSS days for me. I’ve done a few 3 hour zwift organized rides/races and it’s a high quality 3 hours session, but I’ll only do that if the weather outside really sucks.