What's the most weight you've ever lost during a single run/workout?

i ate a huge dinner, weighed myself before sleeping, was 115 lbs.

woke up at 5:30am, rolled from the bed into my running shoes, 10 miles later was 108 lbs.

that was the most i ever weighed, i ate so much that dinner. i'm usually 106-110.

i weighed 89 lbs 8 months ago and now i weigh 115, im slow and fat FML

I lost 9 lbs doing 90 minutes on the treadmill one day at the Y a few years ago.

I routinely lose 5 or 6 lbs on an hour run.

I recall losing 9lbs during a hot run a few summers ago.

if we involve pooping too, i think i've done 8 lbs in one run. i'm a huge sweater though commonly have dehydration issues.

I don't have my record, but I regularly lose 6-7 pounds on summer runs when it is in the 90's. I know that I've gone more than that, but at that point I definitely am starting to suffer from dehydration. I don't think I've ever gone past 8.5.

I went from almost 150 to under 140 once, but I took a mad mid-run poop in addition to sweating.

Dropped about 150 lbs last Thurs. He sure was mad.

I think the most I lost was 12 or 13, but that was when I was wrestling and trying to cut weight.

I lost ~15 lbs gross on a brutal 22 miler last summer down here in the SE, net loss was 9 lbs from 175 to 166, I couldn't consume enough water/sport drink.

Everytime anyone of you mention a weight change related to the dump you took on a run I think of the largest sh*t ever South Park episode.

Summer after HS senior year training in the Tampa Bay area doing a 20 miler on July 4th. Started at 7 pm, ran with only a few gas stations for water, weighing 135, finished about 9:30 pm weighing 122 pounds. Within 24 hours was back to 135 pounds but felt crappy for several days.

In the summer, I count on 4 pounds/hour. It's easy to lose 5-7 lbs. Beyond 7.5-8 pounds, my body starts to shut down, although at that point it's probably a combination of heat and water loss. That's about 5% of my body weight.

It depends on the heat and humidity. At the high end, my body keeps sweating to cool down, but it isn't happening.