More accurate marathon time calculator

RunnerElizabeth wrote: »

litsy3 wrote: »

For gender difference (Riegel calculator adapted for some real-life stats), try this one:
http://www.fetcheveryone.com/training-calculators-improvedriegel.php?hours=1&minutes=24&seconds=52&update=Update

Why would I be so much slower if i were a man with the same half time?

Speaking in broad generalizations, women who are equally good at shorter distances are better than men at longer distances. There is a woman in our running group who can run about a 20:30 5k -- pretty fast, but my PR beats her by more than 2 minutes. But she has run a 3:15 marathon, 7 minutes faster than me!