Jay implied this was a change throughout the peloton, but you can still see old school strategies doing well (Bernal for example does huge volume in base from strava).

It has come to the point that tweaking nutrition science to feed athletes better so they can train more is a key aspect of the ultra endurance training (e.g. the Norwegian Iron Men around Olaf Alexander Bu).

Studies have found that humans cannot consume more calories than 2.5x their basal metabolic rate.

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.

>> Someone on the internet wrote "humans cannot consume more calories than 2.5x their basal metabolic rate" -- which study might they be quoting?

> I am not aware of a specific study that states that humans cannot consume more calories than 2.5x their basal metabolic rate. Basal metabolic rate (BMR) is the amount of energy a person needs to maintain basic bodily functions such as breathing and digestion, and it can vary greatly depending on factors such as age, sex, and muscle mass. However, the total daily calorie needs of an individual also depend on their level of physical activity and other lifestyle factors. So, it's likely that this statement is a generalization or an over simplification.

"Incorporating data from overfeeding studies, we find evidence for an alimentary energy supply limit in humans of ~2.5× BMR"

A good book the topic is Herman Ponzer's "Burn"

The main issue seems the surface area of the GI tract.