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
Yawns are more contagious among people with closer relationships.
163
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The human body contains over a billion miles of DNA.
147
The average sperm cell swims at 8 inches per hour.
76