Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
The human brain uses approximately as much energy as a 10 watt light bulb.
120
The human brain has the capacity to store everything that you experience.
4k
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62
When you take a step, you are using up to 200 muscles.
886
The average sperm cell swims at 8 inches per hour.
76
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22