I’m a much better cyclist than a runner. However i often thought that spending calories by running is much more effcient than cycling. Thus i did the math to check this.
A few days i did a screenshot of a the Activity app on my iPhone.
My calories count was 5319 kcals for this day, 2917 were based on activities. However i had to cycle 106 km for it in 3 hours 27 minutes to spend 951+1355 kcals for it at my usual 200 watts limit for the indoor ride and 250 watts limit for a not so flat outdoor ride. 2306 kcal. 21 kcal per km. 11 kcal per minute. The bicycle rides were measured with powermeters.
When i ran 12.6 km i spend 1.106 kcal in 1 hour 24 minutes. 87 kCal per km. 13 kcal. This was my best 10 km time so for my perspective i was rather fast.
I thought there would be a much larger difference. May be related that i’m a rather slow runner. That said i’m staying with cycling, much better for my knees and i can’t run 3 hours so the total amount of spend kcals is still higher.