Intervals: trainer or road?


New Member
Sep 20, 2002
Do you guys do your interval training on a turbo trainer, or on the road? Most coaches / books seem to advise doing them on a trainer for consistency. I have no problems with 85-90% MHR intervals on the trainer (and keep them consistently within my targets HR zone) but I have a hard time getting my HR above 90% on the trainer. On the road I don't have this problem, even though perceived intensity is about the same. Any thoughts?
I would think that the most scientific training (staying within specific and narrow target heart rate zones) would be best done in the most controllable environment. So based on that, the trainer would work better. No changes of wind, no uphill/downhill issues.


I can see doing it in the winter or maybe from time to time in the summer but I would rather sacrifice some performance to keep my brain stimulated.
The trainer has many uses but coming up to the racing season I am an advocate of intervals on the road in racing situations. For example, sprinting off wheels, in response to an atack from another rider. Almost all sessions can be adapted in this way with rest, duration and intensity of efforts maintained. This type of training develops some of the mental aspects of cycling as well as physiological adaptations.
I agree with 2Lap, there's a possibility that adaptations might be slightly different between a constant load on an indoor trainer and outside on the road at the same average power -- due to greater fluctuations in power on the road, which might stimulate a greater quantity of type II fibres, even with longer time trial type intervals (e.g., 20-mins).

Plus, the skill aspect shouldn't be overlooked for sprinting and it does get boring indoors!

Ive been doing alot of interval training on the trainer. It's certainly less boring than just riding on the trainer, but as others have said, you do tend to loose out on other skills provided by on road intervals.

But I will say one thing, no matter where you do it, it certainly helps the training process.

I have a interval training program that I found in a cycling mag. It requires a warm up (typicaly 5 - 10 minutes) then a 5 second sprint, followed by a 5 minutes recovery. This continues for 30 minutes and then a 5 minutes warm down.
There's certainly *good* reasons for riding on the trainer (e.g., no cars!, no stop signs etc) and i often train indoors for that reason!

However, one thing worth bearing in mind is that for peak power sprint efforts, depending on your age, gender, and sprint ability, most commercially available indoor trainers (that *i've* used and seen) can't generate enough resistive forces to cope with sprints, and you'll need to do these on the road.

With all - out efforts shorter than ~ 20-secs, most endurance trained males will be able to exceed the power generating capabilities of the trainer.

It's definitely better to do sprint work outdoors.

Thanks Ric - you've just pointed out what I've noticed, being that I can "overpower" my trainer. I can spin a 53*12 gear at 150 rpm on the trainer at its highest resistence setting (think 85km/h +) something that I'm not likely to achieve on the road! Was wondering if I needed to upgrade my trainer?

The high cadence might be useful for being a track sprinter (not sure what events you take part in).

I'm unaware of commercially available trainers that can withstand peak power (sprints) outputs. There's only two that i can think of which are the Velodyne and the Kingcycle -- which off the top of my head are both about UK£2000. Even with these two, i'm not entirely sure they can generate enough resistance (depending on how good a sprinter you are).

That being, said *i* would *exclusively* perform sprint (not interval) training outdoors, because of several issues (e.g., don't want trainer to fall over, resistive issues above, skill).