@Nate_Pearson the law of thermodynamics is true however it is useless and over simplistic on its description. As you said above calories in Vs calories burned (as opposed to just cico) is a better way to describe it. Explaining why there are more calories in or out is however far more complicated and the reason why it isn’t quite as simple as move more and/or eat less. This is because these two variables are not independent of each other (the cico model that is part of conventional wisdom however assumes that they are) eg: calories out via exercise likely affects your calories in through hunger, what you eat and how much as well as how much you move throughout the rest of the day and many other things which we cannot possibly calculate and the same with ‘calories in’ which simply must affect your calories out again by how much and what you eat as well as timing and all the effects this has on metabolism and energy levels and on and on…
I would love you to get Jason Fung on the show but an even better guest would be Dr Peter Attia, who is a well known for all his n+1 experiments, especially around ketosis, hflc and endurance sports (mostly cycling) and would be an even better fit for the show.