Why do young people tend to feel more exhausted? Because they haven't gotten enough sleep. It's that simple.

Eight hours of sleep is a lie from the industrial age. Adults are advised to sleep more than 7 hours a day because 7 hours is enough to keep you from dying. Given the current work pressure on young people, the appropriate sleep time is nine to ten hours.
Sleep quality is also poor. Don't eat, play games, or look at your phone or computer three hours before bed, but that's impossible for most people nowadays. Frequent late-night snacks, staying up until 2 or 3 a.m., and only sleeping the basic seven or eight hours is completely insufficient.
Strong resilience can actually mask problems. Reproductive system health is an indicator: women check their menstrual cycle, men check sperm motility. When the body is unhealthy, the first system to give up is the reproductive system. When under stress, sperm motility drops; getting enough sleep helps recovery.
Sleeping cannot relieve exhaustion alone; you need to go to bed at 9 p.m. and sleep well for a month to see improvement. But a lack of control over one's own time makes people reluctant to sleep early, leading to late-night phone scrolling. The psychological need for personal time conflicts with the physiological need for sleep, making it hard to choose.
Sleep hygiene involves not just duration but also rhythm. Humans evolved over tens of millions of years to wake at sunrise, but a few hundred years of industrialization are not enough to adapt. For the same 10 hours, sleeping from 10 p.m. to 8 a.m. is better than from 2 a.m. to 12 p.m. The older you get, the earlier you wake up; after 35, you can't stay up late—young people can sleep until noon after going to bed at 2 a.m., but middle-aged people wake up at 8 a.m. and still can't fall back asleep.
Overtiredness actually makes it harder to sleep because cortisol levels are high and nerves are stressed. Replenishing carbs, relaxing early, taking a bath to create temperature changes, listening to meditation BGM—all help. Doctors tell me: anything after 9 p.m. counts as staying up late. I obediently went to bed early for a month, and my sperm motility improved from "worse than an 80-year-old man" to "very healthy."
The promotion of eight hours of sleep is very harmful, causing stress for those who sleep more. But Lu Xiaojun sleeps until 10 or 11 p.m., Gu Ailing sleeps ten hours, Gao Tingyu sleeps 10 to 12 hours, Su Bingtian sleeps at 10 p.m., and Kipchoge sleeps ten hours. Athletes sleep 10 to 12 hours because of high-intensity training that requires recovery. Ordinary people who work hard and mentally strain also need longer sleep. Eight hours is just the basic duration when you're not doing anything.