Running Facts

There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.

According to a 2010 study by bio-mechanical expert Dr. Peter Weyand, humans could theoretically run up to 40 mph if our limbs could handle the ground forces—nearly 50% faster than Usain Bolt's record top speed of 27.8 mph.

A man called Dean Karnazes ran 350 miles in 80 hours with no sleep, ran a marathon in the South Pole in -25 °C temperatures without snowshoes, and ran 50 marathons in 50 states in 50 days.