When you take a step, you are using up to 200 muscles.
886
Your body is creating and killing about 2.4 million red blood cells per second.
17
The average sperm cell swims at 8 inches per hour.
76
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Yawns are more contagious among people with closer relationships.
163
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
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