If you don’t race, you may wonder whether you would benefit from using a power meter. But a power meter can be an effective tool to help with a goal that isn’t strictly related to racing: weight loss.
What’s more, the learning curve required to use it for that purpose is a lot simpler than for training. At the heart of a power meter’s data is a value called the kilojoule (often abbreviated as kJ). A joule is a measure of energy, or work, like a calorie. There are roughly four kJs per food calorie. But, says Allen Lim, a physiologist, cookbook author, and founder of energy food company Skratch Labs, “the human body is only 20- to 25-percent efficient at transferring energy to work; the rest gets lost as heat.”