Most Helpful Guy
They can be able to get up and "not seem tired" but the lack of sleep causes many different problems that are not visible to the eye.
6 hours or less sleep sognifically weakens various immunological capabilities of your body. It weakens the ability to focus on things and makes it harder to memorize things in long term memory.
Peak physical performance also suffers from the lack of sleep.
Prolonged lack of sleep has been said to increase the risk of cancer and various tumours due the reduced immunological capabilitites. The less sleep ypu get the more severe these symptoms usually are. A young person might not appear so tired on the naked eye but deep down nobody escapes the need to sleep.
7-9 hours is the ideal time suggested that everyone should sleep per night.
Most Helpful Girl
I'm not sure if there's a scientific reason, but I would sleep at like 2 am from the age of 7-12, and it was very broken sleep, I think my body just got used to running on almost nothing.