Why do my hands swell when I run?

Mine swell more when cold and if under hydrated it's worse.

It's pretty normal for hands  to swell while running.

Read the article on Livestrong someone posted.

Mostly has to do with position of hands to heart, but other factors like heat can add to it.

Mine too. Not bad, just enough that if I'm wearing rings, they won't come off. My feet swell, too, especially in the heat, and they swell during long, hot bike rides too - enough that I had to buy new bike shoes because my feet would be KILLING me after long rides, and bike shoes don't give like running shoes do.

Post-race this past weekend, I went to put my five fingers on for recovery shoes and my toes were so fat that I couldn't put them on. I ended up walking around barefoot.

My hands swell if it is cold and I have warmed up. Normally after a couple of miles I will notice it - early mornings or winter.

Sometimes I will find that my hands are fine until I stop/finish. Then they swell after as the heat around my body levels out (also running in the cold)