Up/down Terrain & Variability Index

Searched the forum (and others), can’t find the answer to my question:

Is there a way (or even a reason) to factor in elevation gain/loss to the Variability Index (VI; Training Peaks)?

Not so much for racing but for doing interval work outdoors, is there a way to smooth choppy power on constantly undulating terrain?


Why? The power is the power regardless of the terrain. That’s why you use power.

Presumably it will be harder to have a lower VI, all else being equal, if there is more change in elevation (hills vs flats).

My other half – “even a reason”?

I guess I’ve been conditioned by trainer workouts where my power doesn’t have +/- 20w fluctuations.

Learning curve of re-learning how to keep power on the pedals.

Your obviously not going to have the +/- 5w you can get on a trainer. Just aim for the middle of the target zone and do your best. Try not to have too steep of declines where you can’t put down power.

Or pick terrain that roughly matches your interval length. I have some 2 minute hills, and some 20 minute hills nearby that I ride depending on what is on the workout schedule.

It’s the other way around. Its physiologically easier to have a low VI (at the same ave power) because surges in power cause metabolic and muscular fatigue that is not perfectly recouped on the easy bits (eg downhill). However the paradox is that a VI of 1.0 (NP = AveP) causes a slower climbing time and more time on the course. So basically a high VI (up to a tipping point) is faster on a hilly course but a low VI is metabolically efficient.

Back to your question is there a way too smooth the VI on a hilly course? Yes, simply ride at an even power up and down…but what would be your objective in doing this?

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