Wednesday, February 24, 2010

A Group 24th February




On a day with far less rain than was forecast, Jeff led us 44.04 sporting miles from Merstham to Denbies. Moving average speed 12.1 mph, 2920 feet of ascent, maximum speed 32.9 mph on the road to Balcombe and 2281 calories.

An update to my software now produces estimates of power used - the average for this ride was 90 watts, with a peak five minutes of 190 watts. For comparison, a ride along the Thames to Staines averages less than 50 watts and Alpe d'Huez averages about 200 watts.

I'll include the watts from now on.

Mark


6 comments:

Julian said...

Mark——I suspect your peak five minutes of effort were climbing Cobb Lane and coincided with my sitting by the roadside watching Simon mend his puncture! Thank you Jeff for an excellent ride--on the hard side for me, but good to get out from under the weather. I hope you got home without any more crank problems.
Julian

Mark G said...

Hmm - I hadn't drawn attention to that, Julian, but you are right!

But I agree, it was a jolly good day out.

Jeff said...

Mark - I'm intrigued by the apparently symmetrical corellation between climb and calories - one calorie per foot of climb.
Jeff

Jeff said...

Ahem! correlation.

Mark G said...

Yes, I'd spotted that. It's not a typo and it hasn't happened before. I'll keep an eye on it.

(Perhaps with all the effort of calculating Watts it has lost interest in poor old calories).

Mark G said...

Duh, it is a typo. I read the wrong column. (There are quite a lot of columns). My software computes (guesses) the calories as 2281. The GPS also makes a guess at this, quite independently. It says 2725. Which harks back to a conversation Julian and I had about calories last summer - there must be an assumption of the rider's fitness in the algorithm, which is pretty arbitrary. The Watts calculation is likely to be better, as it is just an expression of how much force is needed to move a given mass up a given gradient.

I'll correct the blog so that our errors are at least consistent.