Posted here so others don't make the same (many) mistakes I did yesterday. Trainging for a HM on 6/22 and after taking a month easy (business trips) I wanted to get back to my HM schedule. This meant an 10 mile run this weekend. Mistake #1, I did not rebuild the mileage, I just jumped back into the schedule. I had chores that I needed to take care of, so I didn't get out to run until the middle of the day. It was hotter than I had ever run in.(Mistake #2) I did not hydrate at all during the morning because of said chores (Mistake #3) I have run unsupported runs up to 9 miles with no issues, so I figured 10 would be no big deal (Mistake #4) I did not plan my route with any water sources (Mistake #5) - so by mile 8, I considered whether it was safe to pick up the discarded bottles at the side of the road a drink whatever was in them. I did not bring any money to buy any water, even though I passed about 500 convenience stores during the run. (Mistake #6) I ran my 11 mile route, instead of the 10, because I can HTFU when ever I want to (Mistake #7) Needless to say, it did not go well. I'll sum it up by telling you what one of my neighbors said to my wife. "I saw him leave and he was running, and two hours later he came back... and... well... I guess he was still running" Hope you all can learn something from this. I sure did!

///whack upsida head/// But this isn't a bonk, it's dehydration.

Thanks, I needed the whack upside the head! So it wasn't the lack of nutrients while running, but the lack of water?

Marathon training in 2004. Mile 14 run past the house. Decided not to re-fill water bottle because there was a fountain at mile 15. Fountain turned off (winter) . 65 F/18 C. 20 miler planned. Hit the wall at 15.25 miles . Sunday 8:00 AM. "Mommy there is a man at the door who wants water from the front faucet". Walked the1.5 miles back to the house. I had been running about 15 years and 2 marathons. Do we ever learn?

Lack of water AND lack of electrolytes. Less than one hour....should be OK with just water. Up to 2 hours...make sure you get electrolytes, so drink a sports drink or eat pretzels or whatever; just get some salt. This is really important when the weather is hot and/or humid. Over 2 hours...you need nutrients as well.

I had similar issues this weekend... I wonder if some of your mistakes wouldn't have been when it was cooler but since it's warmer they became mistakes... I went out for a 10miler thinking i'd grab water at 6 when my friend would leave me and be fine... well i got water at 6 and 8 but could only make it to 9 because I was out of get-up-and-go... at 9 it just started to return but I decided not to press my luck to 10. I've only ever used water because normally all the other things taste like crap, but I can tell you that at mile 6 I had the largest idea a cold capri sun would have tasted AWESOME... not that I had one available.

Seriously. Anything would have tasted better than what I had (nothing...) I wonder that too, as to whether I would have been okay if it had been cooler. But then again, I would have made these mistakes sooner or later. Better to be sooner. Ken (campisi): I think you said what I was afraid to say myself.

Where in San Jose are you? I'm going to be traveling to San Jose 7/21-7/25. Holy cow, that's quite a race you've signed up for. Have the MI'ers informed you of what it's going to be like at that time of year?!?! What made you sign up for this race? Thanks again for the reply.

Losing as little as 2% of the fluids in your body can have a negative effect on muscle performance, that's less than 6 ounces for a 150 pound runner. Most people would be surprised at how much water they lose on a run. I've weighed myself before and after long runs and found that I've lost as much as 8 pounds, that's nearly a gallon of water and 5% of my body weight. Neglecting to replace what you lose can have serious consequences, not just net you a bad run. I typically alternate between a liter of water or sports drink every hour on summer runs. Nutrition would not be an issue on a 10 mile run. I've gone as far as 24 miles on nothing but water before with no trouble. Most of us can store around 2000 calories worth of glycogen in our muscles which is easily good for 20 miles or more at a long run pace. There is some pretty good information on running and dehydration in the following article by Pete Phitzinger: THE DANGERS OF DEHYDRATION Tom

I think your math may be incorrect. 2% of 150 lbs is 3 lbs. Greg

I think he meant 2% of body fluid, though the math would still be off. Water makes up about 70% of body mass, so 2% of 105 lbs would be 2.1 lbs.