Does Zwift adjust for age and weight in calculating output and calories?

I notice that the calories burned when I do Zwift rides register at about half of what shows on my Apple Watch when I start an indoor-bike workout recording at the same time. Just wondering if any adjustments happen in Zwift relative to age etc. 

Hi Susanne

I believe Zwift calorie expenditure is based on power if you have a power meter on your set up.

If you don’t have a power meter, your age, current weight and distance traveled  over time are used to approximate calorie expenditure.

There are a number of algorithms used to measure the number of calories burned and they all, pretty much, have different results. Non of them are pin-point accurate, you’d need lab conditions to make that kind of assessment.

As an ex-PT, I have always recommended following the route that gives the lowest number of calories burned over a given time.