Power Qusetion

[Odion]

New to this power thing, so hopefully someone can help me out.

 

Can you extrapolate a 10min normalised power output to give you your FTP.

[BikeMax]

 

New to this power thing' date=' so hopefully someone can help me out.

 

Can you extrapolate a 10min normalised power output to give you your FTP.[/quote']

 

Hi - you would be strongly advised not to do this as due to the high anaerobic content of a 10 min NP interval, you could be miles off.

 

I would suggest at least a 20 min AP interval (maybe on a climb but at least steady power) and take 95% for a "reasonable" FTP estimate. Even this length may have a percentage of anaerobic work that makes it unreliable.

 

Once you have an idea then I would suggest a set of 2 x 20 intervals flat out but evenly paced and take the average you can maintain for both as a pretty good guide.

 

Better still - 60 min TT

 

[Odion]

Thanks Bikemax. In the interim I've done 2 x 20 intervals on a computrainer and used 95% of the higher power interval to calculate my FTP.still need to get the courage to do a 60 min TT on the computrainer.

 

Out of interest (anyone out there) would it it be alright to do the intervals on a 2% gradient rather than a flat course. Seems I have more motivation on an incline.

[Christie]

I test lower FTP on the indoor trainer compared to on the road. Perhaps due to higher body temperature on the idt?

[The Saint]

Thank goodness Bikemax answered this and not a representative from Eskom

[Odion]

Christie, what percentage difference do you experience indoors vs. outdoors

[Christie]

On the IDT I get about 6 to 8% less.

[JasonW]

On the IDT I get about 6 to 8% less.

 

I find the same thing. I'm more inclined to think that the difference is due to motivation (or lack thereof!) rather than heat.

 

I think that it is best to test your FTP on an incline as it prevents you from slacking or freewheeling. However if the incline is to steep then I think that you can inflate your results by going into the VO2 max zone.

[Odion]

I saw numbers being thrown about of about a 15% difference, which seemed a little high. The 6 to 8% seems more realistic.

 

Currently I do the FTP test or rather a 20min test on an incline which varies between 1.5 to 2.5%. The interval lasts about 24min in total. Seems a lot "easier" than a pancake flat course

 

Odion2008-03-19 06:14:55

[JasonW]

My theory is that it is easier to pedal against a steady resistance, but there are other theories. I seem to recall this being discussed on the Hub a while back and on cyclingnews.com.

I don't think that you would get inflated results from a 1.5 to 2.5 % incline.

[Willehond]

An incline is great, but if you don't have one handy and live in the Cape, just wait for the Southeaster to howl and hit it head on.  Does the trick