The average sperm cell swims at 8 inches per hour.
76
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
The human brain has the capacity to store everything that you experience.
4k
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22