Cramps / Diarrhea

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Cramps / Diarrhea

Postby jyjyjy81 » Sat Aug 14, 2010 9:57 am


This is probably a typical situation you deal with but here goes just the same.

Yesterday I went for a 125 km bike ride with friends. Near the end of the ride I developed sudden abdominal cramping follwed by explosive diarrhea (luckily I had time to run into a nearby donut shop!!). I have never experienced this before.

I am a 45 year old male 6' 190 lbs. I filled each 700 ml water bottle with two scoops of Perpetuem and half way through the ride again filled each bottle with a package each of Perpetuem. The tempo of the ride was above my usaul endurance (aerobic) pace and the last half of the ride was +30 degrees Celsius and very humid. I also ingested a banana and one gel on the first half of the ride.

I have raced three 12 hour cycling events over the past 6 months and lots of longer rides without incidence. I never have GI issues outside of exercise as well.

During those events I used eLoad , gels, water and a variety of "real food" like sandwiches, nuts Coke, bananas etc.

What was different this time?
1. Although I have used Perpetuem briefly recently I have yet to use it in this quantity and exclusively.
2. Hotter and more humid yesterday than any of these events and I am a big sweater.
3. Somewhat hopped up tempo.

My of these:

I became dehydrated which created intestinal distress.
I was ingesting too much carbo which created intestinal distress.
Perpetuem doesn't agree with me.

Any suggestions / guidance are more than welcome. I am a little freaked out as I have a +24 hour event in 5 weeks and I really do not want any type of GI problems.


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Joined: Sat Aug 14, 2010 8:50 am

Re: Cramps / Diarrhea

Postby steve-born » Mon Aug 16, 2010 10:34 am

Hello J -

My apologies for the tardiness of this reply. For the past several days I had been working on getting the next issue of Endurance News completed, as well as the text for a couple of Athlete Education Series pieces, and I just got back from a work-related trip during which I didn't have much Internet time to spend.

Anyway, two of the three things that you mentioned as being potential culprits for the issues you had jumped out at me. You said that it was hotter and more humid yesterday than some-to-all of the other events that you had done and that you had been going at an increased tempo/pace during this particular ride. 30C - 32C is about 86 - almost 90 degrees, which is definitely hot when you're not acclimated to those temperatures. At 30C, if the humidity is 80%, you're looking at a heat index of 38C/100F. At 85% humidity the heat index is 39C/102F. Kick that humidity up to 90% and you're now at 41C/31F. Any one of those scenarios! That's hot!

Both of those things - the heat/humidity and the increased pace - will diminish digestive capabilities significantly, which means that less calories would, in my opinion, have served you a lot better. Also, if you're not acclimated to the weather conditions then your fluid and calorie intake would increase.

Normally, at 190 lbs, an intake of 2 scoops or Perpetuem an hour (270 calories) would be appropriate. However, under these conditions, as well as your increased pace - again, both of these things decreasing digestive capabilities to some degree - I think less Perpetuem, about 1.5 scoops/hour, would have worked better. Yes, that "only" gives you 202.5 calories per hour, but remember that your muscle glycogen stores and the calories from body fat stores will help to "bridge the gap" between what you're burning and what your body is comfortably able to accept in return from you.

I also think that 700 ml (about 24 ounces) per hour is not quite enough when the temperature/humidity is that high, and especially so if you're not acclimated to that. Also, keep in mind that when you put 2 scoops of Perpetuem in a 700 ml bottle, you're not going to end up with 700 ml of actual fluid left... because of the powder taking up some of the space within the bottle, the fluid you have left in the bottle will be diminished somewhat, perhaps 3-3.5 ounces less (about 90-100 ml).

I don't know how long it took you to do this ride, but for the sake of an even number, let's say it was 4 hours (125 km/78 miles in 4 hours = 31.25 km/hour = 19.75 mi/hour). If I were doing this ride under the same conditions, and at the same pace (and we weight pretty close to the same in terms of weight; I'm a little heavier), I would suggest the following:

1) Make a 3-hour bottle of Perpetuem, the bottle containing 4.5 scoops (607.5 calories = 202.5 calories per hour) to 5 scoops (675 calories = 225 calories/hour). Even though you will have some fluid left in the bottle, over the course of 3 hours it's going to somewhat minimal, so in essence this is a "calories only" bottle.

With this 3-hour bottle you will, of course, have 3 hours of calorie requirements taken care of. The remaining hour will be fulfilled from 1/2 of a flask of Hammer Gel. Carry a full flask, just in case you're out there longer than expected, but know that about 1/2 of a flask of Hammer Gel should easily cover that remaining hour. Now, you can consume this at any time, be it the beginning of the ride or at any point in the ride... just remember that this 1/2 flask of Hammer Gel will cover a full hour's worth of calorie requirements. No Perpetuem during that hour.

2) From a separate source (water bottle, Camelback, hydration system), I would suggest consuming 750 - 850 ml of water per hour (equal to about 25 - 29 ounces per hour), the higher amount - and perhaps even slightly higher - when the heat index is that high.

3) 3-6 Endurolytes per hour. The calories from your Perpetuem and Hammer Gel will cover your calorie requirements, the fluids - which are coming from a source independent of your Perpetuem bottle and flask of Hammer Gel - will take care of your hydration requirements, and the Endurolytes will take care of your electrolytic mineral needs.

I think this would be a stellar plan/protocol to use as your guideline. The key thing is that when it comes to calories - and especially when the temperatures/humidity/pace are high - you want to err on the "not quite enough side." Fixing that problem is easy... you simply consume more calories. But if you've oversupplied your body with too many calories, that's a lot harder problem to resolve and oftentimes the body lets you know courtesy of some not-so-pleasant stomach-related issues, such as what you've experienced.

To sum up:

1) I think you can/should cut back on your calories a bit, especially when the weather and pace are high, and most definitely when you're not acclimated to that higher-than-accustomed-to temperatures/pace.

2) I think you need to increase your fluid intake as well, while also remembering to take Endurolytes to fulfill that crucial component of your fueling.

I hope these suggestions help!

Sincerely -

Steve Born
Fueling Expert
Event Sponsorship Coordinator
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