The key insight is that you can eat more, but your body will not consume it. https://www.science.org/doi/10.1126/sciadv.aaw0341 https://www.science.org/doi/10.

The key insight is that you can eat more, but your body will not consume it. https://www.science.org/doi/10.1126/sciadv.aaw0341 https://www.science.org/doi/10.1126/sciadv.aaw0341 And nobody is saying you can't expend more energy for shorter times. It is just that you can't sustain it over long times because of our metabolic limits.