It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The human brain doesn't stop developing until about 25 years old.
102
Every year your body replaces 98% of your atoms.
119
When you take a step, you are using up to 200 muscles.
886
The average sperm cell swims at 8 inches per hour.
76
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Enamel is hardest substance in the human body.
61
Yawns are more contagious among people with closer relationships.
163