Why can your body have a “sleep debt” but not a “sleep surplus”?

Question

Why does my 15 hours of sleep on the weekend not counteract the 4 hours I get on a weeknight?

In: Biology

Answer 1

Not getting enough sleep doesn’t let the body and brain finish its cycles. The damage and lack of sleep build up (debt)

Once the body is finished with the cycles, that’s it. It can’t store sleep to repair future damage and build future neural pathways. It can only work on what has already been done.