Indoor vs outdoor cadence (impacting FTP)

Like some of the members on TR, I’ve noticed hitting my outdoor target power easier vs. indoors, and generally speaking feel much stronger outside (can also confirm indoor cooling isn’t an issue).

One thing I’ve noticed is that I tend to spin much slower outdoors vs indoors. Could be the mechanic of being in ERG vs gears / climbing hills outside, but has there been any findings around higher indoor cadence negatively impacting FTP?

I find that my natural indoor cadence happens to be higher (100s) vs outdoors (70-80s), and can complete outdoor TR workouts much easier vs indoor ones.

Should I force myself to spin slower in doors if this is the case?


Same here - both in terms of cadence and effort. I consistently average 91-92rpm outside, and 97-98 on the trainer. I wonder if the periods of coasting (which are inevitable however much you try to avoid them - traffic, fast downhill corners, etc) are factored into the calculation outside?

Hm so I actually accounted for that, with coasting my avg RPM is actually down to high 70s or low 80s – was comparing rpm during my intervals which has a 20rpm difference.

It could also be that I’m not used to using ERG based on some reading. Could try forcing myself to spin lower, will see how that experiment unfolds.

I spin at 100 plus on the turbo and 95 outside on the road bike. Always have. That said I am down at about 90-92 on the TT bike. Power is the same though…if you slower your cadence the resistance increases in Erg. I find my HR is higher if I spin faster but it feels more comfortable.

I’ve had a similar experience. Though I’ve been riding for over 20 years and had athletic experience (D1 college rowing), I just started using TrainerRoad last spring and training with more purpose at the bike. Initially my spin on the trainer was in the 80’s, and hitting 90 was tough, but over the past few months my spin has improved a lot. I still tend to spin lower outside, but have also tried to spin higher outside, though I have to be intentional about it. As I’ve raised my FTP, I’ve intentionally started adding more lower cadence work, forcing myself down into the 80’s and high 70’s during some endurance/tempo/sspot workouts, and I feel like this has helped my strength and make further power gains (this is all in erg mode). I also feel like I finally understand what “aerobic power” really means and feels like from watching heartrate/power/cadence and seeing how they all work together (not that I didn’t understand it before, but I feel like I have more of a “feel” for it now).