# Training & Nutrition - kJ to Calories

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View Full Version : kJ to Calories

UmneyDurak
07-23-07, 10:25 AM
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.

Turboem1
07-24-07, 06:47 AM
To convert kJ to Calories multiply the amount by .239

raptor3x
07-24-07, 07:52 AM
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%.