Power and off road demands

[Woofer]

Lots of folks have reported that their power recorded off road during races does not come close to what they can do on the road - reasonably deducting that there is something about off road riding that is not detected by one's powermeter. There is a study referenced in 6 Feb 2006 Velonews by Keith Fritz and Gig Leadbetter where they attempted VO2 max studies in the lab on a trainer and in the field on mountain bikes and found a slightly greater demand in the field but it was not statistically signficant. I could not find this on pubmed but maybe I used the wrong search terms.

 

[frenchyge]

Lots of folks have reported that their power recorded off road during races does not come close to what they can do on the road - reasonably deducting that there is something about off road riding that is not detected by one's powermeter.

I don't ride off-road, but is it possible that the difference comes from the need to occasionally stop pedalling or reduce power to navigate obstacles, sharp corners, steep downhill sections, etc.?

 

[velomanct]

Lots of folks have reported that their power recorded off road during races does not come close to what they can do on the road - reasonably deducting that there is something about off road riding that is not detected by one's powermeter. There is a study referenced in 6 Feb 2006 Velonews by Keith Fritz and Gig Leadbetter where they attempted VO2 max studies in the lab on a trainer and in the field on mountain bikes and found a slightly greater demand in the field but it was not statistically signficant. I could not find this on pubmed but maybe I used the wrong search terms.

Why is this surprising?

Anyone can tell you that average power off road would always be considerably less than on the road. I hope I don't need to explain why.

 

[whoawhoa]

I don't ride off-road, but is it possible that the difference comes from the need to occasionally stop pedalling or reduce power to navigate obstacles, sharp corners, steep downhill sections, etc.?

Although this seems the obvious answer, I've read people claiming power was down on almost any off-road surfacae, e.g. riding up a relatively smooth gravel road climb.

 

[frenchyge]

Although this seems the obvious answer, I've read people claiming power was down on almost any off-road surfacae, e.g. riding up a relatively smooth gravel road climb.

Hmmm.... bike losses not associated with the drivetrain (ie, suspension)? Is it still a problem when riding a MTBs on the road?

 

[whoawhoa]

Anyone noticed what affect there is on power when riding on a bumpy road?

 

[velomanct]

Anyone noticed what affect there is on power when riding on a bumpy road?

Sure do. Anything that disrupts your rythmn or efficiency will lower your power.