If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Enamel is hardest substance in the human body.
61
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
The human brain doesn't stop developing until about 25 years old.
102