alt Hacker News> * The human body is way more complex than CICO*
Genuine quesion - if I eat 1500 calories today and do a measured 2000 calories of work on a treadmill, where did that extra 500 calories of energy come from?
Are you suggesting my body can create energy from nothing?
Generally your liver will store between 12 and 24 hours of calories in the form of glucose. After that, it's likely fat stores from adopose tissue (fat cells)