[andy_ppp]

Great article; it got me wondering how much the oxygen weighs that an elite runner would use in the course of a marathon...

[yzzxy]

For the Berlin track (Because it's level and close to sea level), and the average elite:

1.00 atm * 8.1L = n * 0.0821 * 331.8K

n = 0.30 mol, @ 32.00 g/mol = 9.5 grams 02