Wednesday, September 14, 2005

My First Ever DNF - Ironman Wisconsin 2005

The one and only DNF (Did Not Finish) I have ever suffered in my life was Ironman Wisconsin 2005. I didn't really write a race report for the race. Rather, I posted a review of what happened in an attempt to diagnose what went wrong. What I posted, on, is copied below, along with some of the comments I received as a result.

When it was all said and done, what I ultimately concluded is that I consumed too much water during the race, seriously diluting my electrolyte levels. Anyway, the "report" of sorts...

This isn't as much a race report as it is an attempt to lay out the details of my race in hopes of understanding the cause of my demise. IMWI '05 was my 4th IM, having also done each of the previous three IMWI's. I finished all of them until this year where I fell about 4 miles short.

Brief history of my IM past:

IMWI '02: Mild weather, about the best fitness of my life, finished in 11:37. Felt pretty good the whole way except some stomach discomfort through the middle to latter part of the run.

IMWI '03: Very hot weather, a bit less fit than '02, finished in 12:00. Physically felt much the same as '02, although I considered hitting the med tent after the finish for an IV. But there were a lot of folks worse off than I, and I started feeling better after some time and food.

IMWI '04: Again hot weather, quite a bit less fit than previous years, finished in 12:48. Again, Felt pretty good the whole way except some stomach discomfort through the middle to latter part of the run.

Basic nutrition for these IMs was all about the same, except I added more water and sodium for the hotter races. I used Cytomax, water, Hammergel and Clif Bars on the bike, plus a mix of Succeed and Endurolytes, to get about 350 cals and 800 to 1000 mg sodium per hour during the bike at least for the hot races. For the hot races, I took in about 24 oz Cytomax per hour, plus anywhere from 24 to 48 oz of water per hour. On the run, I find it MUCH harder to measure and track just exactly how much stuff I'm consuming. Generally I'd try to take in some Gatorade at most of the aid stations, plus some water throughout by carrying a bottle of ice water, kept taking in salt tablets at the same rate, and a shot of gel about every 30 min.

Onto this year. I made a couple changes to the plan this year. First, I backed off a bit on the calories, thinking excess calories were contributing to my stomach discomfort later in the run. This year, I planned on about 250 cals per hour. Second, I decided to rely on the Gatorade Endurance from the aid stations rather than hauling along my own supply of Cytomax. I followed this basic plan for most of my long training rides with what I perceived to be good results. A couple of my long rides were in very hot weather and I finished them feeling pretty decent.

My run training was non-existent going into this race. I had recurring calf and achilles injuries that brought my running to a halt. I did the St. Croix Half Ironman on May 1 in 6:03, and that was actually my last "long" run of the year. I truly was able to do very little running, and sporadic at best, front mid-May to race day. I probably ran a total of 20 miles in the 4 months preceding IM. A reasonable person would not have raced, but I decided to give it a go anyway thinking the worst case would have me walking a major portion of the run. I was okay with that. My swim training had been weak, but I had no real concerns about it. My bike training had been adequate...not as much as I had done in previous years, but my long rides were going pretty well so I was confident I could come into T2 feeling pretty decent.

Here's how the day went.

Up at 3AM for a liquid breakfast of 2 Boosts and water. Back to sleep.

Up again at 4:30, another Boost and some water.

At 6:30 I had one GU and about 12 oz of water.

Took it very easy on the swim. Avg HR was 141 which is very low for me. My HR usually rockets on the swim due to adrenaline. Swim time about 1:28.

Urinated at T1, had one small cup of water.

Sipped on water the first 30 min. of bike, then started into my plan as follows. One 24 oz bottle of Gatorade Endurance per hour, about 1/3rd of a bottle every 20 min. Approx one 24 oz bottle of water per hour, also about 1/3rd of a bottle every 20 min. I was drinking one or the other every 10 min. As the temperatures went up I increased my intake of water to as much as 1.5 to 2 bottles per hour, which is much the same as I have done successfully in past hot IMs. I took one Succeed cap every hour and about 1.5 oz of Hammergel every hour. So that plan was giving me about 260 cals per hour and 950-1000 mg Sodium per hour consistently throughout the ride, with an increasing rate of water intake as the temperatures drove up into the 90s.

I think I paced the bike well. I held a pace that felt easy for the first 60 miles, keeping my HR usually below 150. From mile 60 to the end of the ride I really felt quite good aside from just getting uncomfortable being on a bike that long. I was feeling stronger than most of the people looked to be feeling, and passing lots of people...not so much because I was increasing my pace, but because lots of people were slowing down.

Since it was so windy, I had no good way to gauge how much I was sweating during the ride. I urinated twice during the bike, and again at T2. My avg HR for the ride was 153, and my bike split was about 6:25.

The run is where things get much less "calculated". I don't like to carry too much with me aside from a flask of gel, so I rely on the aid stations for all my liquid. And, taking it from those little cups with varying amounts in each, with my brain getting fuzzy, it's hard to know how much I'm getting. In general I was trying to take one cup of Gatorade Endurance at each aid station. I did carry a water bottle with me, as I've done in the past, keeping it filled with water and ice. I would sip on this from time to time, but probably used most of that water to spray on my head and body. I was still taking about 1.5 oz of Hammergel and one Succeed cap per hour.

Half way through the run, I found that my high tech salt tablet container (Tic Tac box) had come apart and my Succeed caps had dissolved. From that point I started to add alternatives for sodium by taking some pretzels and chicken broth. I would have a little broth at each aid station that was offering it, while still taking a cup of Gatorade as well. I also started taking some cola at a few aid stations to get some a caffeine. You'd think that crazy mix would make a person nauseous, but I never felt nauseous at any time during the day. In fact, I never really had any significant stomach discomfort all day.

My pace was a slow run (~11 min/mi) for about the first 11 miles, and mostly walking about 15 min/mi after that. My HR was pretty low, probably bouncing around from around 115 to 130. I noticed that I did not appear to be sweating much at all, and my shorts were starting to look pretty salty. I thought maybe my low sweat rate was due to the temperatures dropping and the fact that I was mostly walking and not working very hard. I urinated twice during the ~4 hours that I was out there.

Around mile 20 I was actually feeling pretty decent and started doing some running again for a mile and a half, or so. A bit past mile 22, I very suddenly started to feel disoriented and dizzy. I was forced to stop. It was either sit down or fall over, so I sat down. Still feeling very dizzy, I laid down and asked passing athletes to get me some help. The EMTs where there within a few minutes. I told them I needed an ambulance. They checked my HR and blood pressure, and said it the BP was 72/50. It took probably 10 min or so for the ambulance to arrive. They checked the BP again and got something like 110/50 and they were thinking the EMT's reading may have been erroneous. They started an IV in the ambulance. My temperature was 99.something, but I was cold and shivering.

At the med tent I stepped on the scale. At check-in on Friday I was about 165, sans shoes. In the med tent, I looked at the scale and saw 172. I figure at least 2 pounds of that was my shoes, so I estimate I gained about 5 lb during the race. However, I saw my chart later in the tent and they had written my post-race weight as something like 164. I have no idea why or how they made that error. I'm sure I know what I saw on the scale.

In the med tent, my BP seemed to stick around 110/50 or 60, which unfortunately for me is actually lower than normal. The first IV finished and they decided to pull it out. However I continued to feel very cold and still kind of dizzy. I asked them, not once but twice, if maybe they should check my sodium levels, but for some reason they never did. I tried to sit up but still felt bad, so they gave me another IV. I drank some Gatorade and broth. Since they weren't doing anything else for me, I decided maybe food was my only way to recover so I got them to get me a sandwich. I think I was in there a total of about 2 hours and eventually finally felt well enough to stand and walk out of there. For the rest of the evening I actually felt quite good. But, I noticed my whole body was quite puffy. Things like by hands and fingers looked swollen. My ring that normally fits pretty loose was very tight on my finger.

So, folks, what's the deal? Did I actually consume too much liquid, even though I believe it was much the same as I have consumed in past IMs with similar temperatures? Not enough sodium, or too much? Not enough other electrolytes outside of what I was getting from Gatorade Endurance? Could my non-existent run training have played a part, maybe my body not working as efficiently on the run as it should? I'm very interested to hear from coaches, nutritionists, IM vets, on what you think doomed my race, so maybe we can all learn something from it.



Some of the feedback I received...

"Lots of factors playing out here. No way too much sodium at 1 succeed per hour plus 24 oz of Gatorade Endurance. Especially with 24 oz of water on top of that. Not enough likely. You were bloated and not processing fluid through the kidneys. A red flag for low blood sodium.

I personally think plain water is a bad idea during an IM, especially a hot one. At least save the water for the run, when you can't take the sports drinks anymore. Every ounce of water ingested is lowering you blood sodium concentration."



"... when I did IMFL 03 I became VERY dizzy about the last 2 miles of the run and I had been walking a lot of it anyway. I didn't get it but I seriously worried that I might pass out and I think it could have been a blood pressure issue. I recall going into a porta potty and the "room" was spinning as if I were drunk. I was in better shape for IMAZ this year even though my finish times were similar and I had no such dizziness but I worried about it. Sometimes I think the calories/sodium/water/fitness thing is just too much to figure out always...the body is just doing the best it can and sometimes things happen than just aren't preventable no matter how much we try.

Sorry about your DNF so close to the finish line and I am glad you are feeling better."



"I'm not a doctor, and haven't yet tackled an IM, but my guess is that you were hyponytremic caused by too much fluids, not enough sodium, or both. Clues to me are the quantity of liquids you were taking (twice what I take during a half IM, for example on the bike), the amount of urination (seems like a lot), the weight gain, and the puffiness you noticed afterwards. So, I think you either need to drink less liquids, or take more electrolytes. 2 large bottles per hour seems like an awful lot of fluids on the bike. I'm not an expert, just an half-educated guess."



"Generally when I become dizzy and disoriented it comes from either low electrolytes and/or dehydration or a calorie deficit induced bonk.

250 calories/hour would be very light for me and it would eventually catch up with me. When that happens perceived exertion goes up but your HR doesn't necessarily follow.

24 - 48 oz. of plain water is a lot. In an IM I usually go with water to chase calories but for basic hydration needs I stick with Gatorade. If I were forced to guess based on what you have said I'd go with low electrolytes."



"Mental effects would be most likely low blood sugar or hyponatremia.

The low hr on the run points to low blood sugar
The bloating points to hyponatremia

The low blood pressure could very well be exertional hypotension from trying to run.

It's a tough call between dehydration and hyponatremia. A fine line to walk. One thing needed to help figure it out is the sodium content of your sweat. Shouldn't be too hard to find out, I thin hospitals actually do this test. You could bring your own sample and pay cash for the test. But at any rate with a sweat rate test and a test of the sodium content then you'll know how much sodium to replace. "



"... there is a lot of misinformation about the causes and prevention of exercise related hyponatremia. Sodium intake is not necessarily protective of this condition, especially in the context of a hypervolemic condition caused by fluid intake, regardless of tonicity, in excess of sweat and urine rates. The fact that you were peeing every 2 hours supports the hypothesis of hyponatremia secondary to excessive fluid intake. There are some other, less likely causes, but without a blood draw you will be guessing. Weight gain of that magnitude with your symptoms is enough for most medical tents to classify you as hyponatremic or at the very least, on the way.

The strongest factor associated with hyponatremia is fluid intake that exceeeds loss. One could argue that your sodium intake may have staved it off for a longer period, but that has not been proven. Remember that even Gatorade is hypotonic relative to serum sodium concentration. It is a relative scale; think of it as slowly diluting the system. This reflects the recent position stands changes of just about all the major governing bodies and sport medicine associations.

I was thinking about you folks most of the day on Sunday. Fit or not, heat like that will take down large numbers of folks, as the margin for error for pacing, nutrition, hydration, training practices... are reduced to a whisker. Hydration issues sometimes don't rear their head in shorter events as there is less time for a gradual change to become symptomatic. You likely did the right thing by calling it a day before things got worse.

Congratulations on your effort and courage. I respect all the folks who lined up on Sunday regardless of the outcome!"

-Keith M.


... I'm not a doctor, but in my IM races, and other hot weather 1/2 IM's I've done, I've experienced exactly the combination of symptoms you list. In my consultation with the med tent, the diagnosis was low blood sugar and low sodium.

Consider adding a 'natural' sugar, such as fruit during the later half of the bike and into T2. Low sodium you can overcome while racing - low BP you can't. Oranges, watermelon and bananas. All absorb fairly quickly and easily. Coke might not be the best answer.

-Keith J.