Hyggenbodden t1_j26iyeo wrote on December 30, 2022 at 12:34 AM

The body needs time to focus on certain maintenance tasks for which there was no time during the day. Muscles recover, food is digested, the brain is dreaming to help process new information etc.

This is because it was important for our ancestors to completely focus on activities such as hunting while awake and use sleep to recover at night while it is too dark to do much anyway.

tomerFire OP t1_j26jo6f wrote on December 30, 2022 at 12:39 AM

But why this recovery cannot be done while awake

Hyggenbodden t1_j26klz4 wrote on December 30, 2022 at 12:46 AM

It could theoretically be done, but we have evolutionary evolved using sleep as we know it as a recovery strategy. It has shown to be an advantage.

Birds for example also have sleep, but they evolved in a way that only one half of the brain sleeps at any time because that allows them to keep flying while recovering which turned out to be an advantage.

Hyggenbodden t1_j26jz2k wrote on December 30, 2022 at 12:41 AM

The resources are needed for the actual activities.

Like you cannot defragment your harddrive while playing a game, or more general you cannot update the firmware of a device while using it.

Azeranth t1_j270fx3 wrote on December 30, 2022 at 2:40 AM

Digesting food is a big one. You essentially have enough blood (ability to distribute oxygen and calories) to run two of three between your stomach, your brain, and your muscles. One of the reasons working out while on a full stomach causes vomiting is because the stomach is upset about the lack of resources available for it to do its job, so it gives up to protect you from harm.

Alternatively, eating after a long day of work puts you straight to sleep because your muscles need to heal and clean, and your stomach needs to digest dinner. You can't run your whole body at once, and sleep is what we call it when your brain and muscles are turned off to let cleaning, healing, maintaining, ad digesting to happen.