Getting sick after HM race - why?

1. What was your pre-race nutrition? Had you tested it before race day? If you eat/drink something that your body isn't comfortable with before running 13.1 miles then there could obviously be GI issues.

2. You might have over-hydrated during the race. it takes between 15-20 minutes for any liquid intake to be "useful" to the body, if you had excess fluid swishing around in your stomach then it may be that your body wasn't happy with it and rejected it.

3. Blood pooling and venous return could be an issue. Blood is prioritised to your lower body during a lengthy run to maintain muscle use. This prioritising draws blood away from your core sometimes resulting in light-headedness, nausea, cramps, etc.

4. If you were cramping late on it could just be a lack of training or it could be nutrition based. The salt intake could have helped or hindered. Don't forget cramping can mean a shortage of potassium not just a shortage of sodium.

I've probably raised more questions than answers but I would suggest that more miles in your legs and small tweak to your nutrition could be a step in the right direction.

I think you hit the target on many aspects. In last couple of weeks building to the race, I got owned at work and was traveling nonstop. For last 10 days before the race regular hydration levels were low, diet was junk, potassium intake was nil and training was very little.

Race venue was Las Vegas so my pre-race day nutrition was not the same either. Generally I eat while wheat toast w/ PB and bananas. Didn't have any of that this time and 7-8hr journey on day before didn't help the fatigue. More on to it, my corral took off an hour after start time so I was standing for good 90mins before stepping across the start line. All that probably contributed to unfavorable conditions.

As for fluid intake, I was really surprised that I had so much water in the body. I didn't have a feeling of water swishing thru the race but I was real thirsty at the end so probably took down couple of bottles just past the finish line. Body probably didn't like the overwhelming increase in fluid intake? That's my best guess.

Wondering if the low humidity had anything to do with why you drank so much and felt uncomfortable. Saying this as I train pretty much year-round in hot, humid conditions where I do need a lot of water but don't necessarily get really thirsty. I've had some difficulty with drinking too much in races/training runs where the humidity is very low. I'm not used to my mouth being so dry, so I drink a lot, maybe more than I need (since I'm very acclimatized to heat), and end up with sloshing, having to pee on the run, etc. Fortunately it's never progressed to nausea in a race (it has on long runs/rides) but I could see how it could in a longer event such as a marathon or IM.

The other issue is your pre-race nutrition. It really helps to have a portable pre-race breakfast that you have tried out repeatedly in training and know works for you. Then just eat it before every race; take it to those you travel to. I ALWAYS do this as living overseas, who knows what will be available for breakfast, or even if there will be food in the hotel before an early AM race. In my case, it has to be something without wheat or dairy as those tend to upset my stomach if I'm running hard, so it's usually oatmeal, or a rice or oat-based energy bar, maybe a banana, some instant coffee. If I take oatmeal, I even bring a bowl, spoon, and an electric coil (to boil water) so I don't have to stress about whether the hotel will provide that. It sounds kind of OCD, but you don't want months of hard training ruined by something silly like eating the wrong thing for breakfast.

I have two acquaintances who run marathons all over Southeast Asia for fun (?!). They both have had GI issues in the past with local pre-race food so they even carry their own pre-race dinner with them--can of spaghetti sauce, noodles, saucepan, hotplate, bowls. It may not be the most nutritious pre-race meal but it is clean, convenient, and predictable. You don't want to run 26 miles on an upset stomach. The time for enjoying the local cuisine and pigging out on junk food would be after the race, not before.

Three salt tabs and all that stuff seems like overkill to me. I think most people can comfortably do a HM with not much more than some water, depending on how fast you are.