WASHINGTON - Running is one of the simplest ways to get moving. But not everyone wants to log slow, steady miles on repeat.

Most of us have little trouble working out how many milliliters are in 2.4 liters of water (it's 2,400). But the same can't be said when we're asked how many minutes are in 2.4 hours (it's 144).

A new collection of research papers examines how humans conceptualize numbers and the numeral systems we’ve build around them ...

Should you go all out in bursts or settle in for the long haul? Experts explain which ride style helps you build more stamina ...