For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
When you take a step, you are using up to 200 muscles.
886
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average sperm cell swims at 8 inches per hour.
76
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
Chewing gum boosts your brain power.
285