A night without words.
Even though many people were killed yesterday, Li Yu still woke up promptly at 6 a.m., and under his influence, the younger generation in the family also began to enjoy getting up early and running around the mountain woods.
Fitness can be addictive, and so can running.
Once the body gets used to exercise, it stimulates the secretion of dopamine, putting the entire body into a positive cycle.
Before the apocalypse, many people in their twenties and thirties had severely declined physical fitness, some due to lack of exercise, some due to unscientific dietary habits, and others because they couldn't give up certain addictions. It seemed like they couldn't muster the energy for anything, except for certain things that brought them brief happiness.