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 Training & Nutrition Learn how to develop a training schedule that's good for you. What should you eat and drink on your ride? Learn everything you need to know about training and nutrition here.

 07-23-07, 09:25 AM #1 UmneyDurak RacingBear Thread Starter     Join Date: Dec 2004 Location: NorCal Bikes: Posts: 8,813 Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 157 Post(s) kJ to Calories How do you convert kJ reported by a power meter to calories? The manual said, calories burned is roughly roughly .85-.95 of total kJs reported for the ride. A book I am reading says amount of Calories burned is +/- 10% of total kJ, interesting part is +. Then I remember reading something that had a formula which result came out very close to 1:1 ratio. So is this the case of them all being right, and it depends on individual? Thanks.
 07-24-07, 05:47 AM #2 Turboem1 Banned.     Join Date: Aug 2006 Location: Long Island Bikes: Lemond Reno Posts: 883 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) To convert kJ to Calories multiply the amount by .239
07-24-07, 06:52 AM   #3
raptor3x
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 Originally Posted by UmneyDurak How do you convert kJ reported by a power meter to calories? The manual said, calories burned is roughly roughly .85-.95 of total kJs reported for the ride. A book I am reading says amount of Calories burned is +/- 10% of total kJ, interesting part is +. Then I remember reading something that had a formula which result came out very close to 1:1 ratio. So is this the case of them all being right, and it depends on individual? Thanks.

Conveniently enough, you can get a pretty accurate estimate of calories expended by just reading the kJ that you power meter gives you as kCals. This works because 1kCal=~4.4kJ but the average human efficiency is somewhere around 22-23%.