It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
It takes about 20 seconds for a red blood cell to circle the whole body.
102
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
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
The average person's skin weighs twice as much as their brain.
131