(More) Arguments about nutrition on the bike, etc

[Brian S]

Interesting article, and a compelling argument for the use of KISS principles of nutrition and energy during exercise (i.e gatorade vs the rest):
http://triathlon.competitor.com/2011/02 ... ergy_21695#

Pickle juice drinkers are welcome to comment, but I still think that is just gross.

[Josh.E]

And don't forget to ingest your caffeine post exercise
http://jap.physiology.org/content/105/1/7

[jeremy]

Lets not forget the argument for the detriments of use of the KISS principles

examples seen below
http://www.youtube.com/watch?v=PHU27_Xp9Yc

[Chris Watt]

Thanks Brian- this is a subject currently near to my heart and other muscles. For my money flat, freezing cold Coke with a pinch of salt is the ultimate sports drink for those hot summer 2+ hour rides because:

1. Caffeine- increases free fatty acid burning and spares muscle glycogen burn
2. Tons of sugar(s) for rapid uptake by the muscles
3. Cold = better performance (by keeping body temp down- http://www.nytimes.com/2010/04/27/healt ... ef=general)

Fizziology geek warning: there’s a 4th reason but this next bit has a high-nerd factor and is only relevant if you plan to do lots of 3+ hour rides:

Recent research (by Jeukendrup who himself is an Iron-guy) suggests that Coke’s sugar mix (roughly 50/50 blend of glucose/fructose) maximizes how much sugar you can deliver to the working muscle. The rate-limiting factor that determines how much sugar hits the muscle isn’t uptake at the muscle but absorption in the gut. It’s believed that different sugars have different absorption pathways at the cellular level in the gut lining- and that each pathway has a maximal absorption rate. For years that max rate has been thought to be 1 gram/minute. And that’s true if only a single sugar source is used. But by combining sugar types (so-called “multiple transportable carbs”) absorption across the gut has been pushed as high as 1.75 gram/hour. http://www.ncbi.nlm.nih.gov/pubmed/20574242

So what?- does jamming more sugar(s) at the working muscle actually improve performance? Yes, it appears it does:
1. In a study of 2009 Hawaii Ironman finishers there was a close correlation between finishing time and carb intake per hour. (sorry, can’t find the link for this one)
2. Another study showed that both the highest absorption rate as well as percentage improvement compared to a single-sugar source was a 1:1 mix of glucose and fructose- performance was improved by 65%. http://sweatscience.com/how-many-carbs- ... #more-1205

So- for endurance sport anyway- Coke really is it. (and in case I’m starting to sounds like a shill for the Coca-Cola Corporation™ let me go on record that otherwise it’s a completely zero-nutrition, obesigenic, chronic disease causing toxin to be avoided unless you've been going hard for 3 or more hours)

Cheers,
Chris

[Josh.E]

Is that canadian Coke?
American Coke is made with high fructose corn syrup, if I'm not mistaken.

I've actually been trying to figure out if the whole Canadian Coke not having HFCS is a myth or not.

[AdamD]

wow thats actually really interesting you should mention that Josh.
In California a bunch of us noticed it tasted slightly different, but I didn't realize that was the case.

[Josh.E]

I've been wondering about the alleged dangers of reactive carbonyls in HFCS vs pure sucrose (cane sugar). Both contain around teh same % glucose to fructose, but in cane sugar they are "chemically bound".
Bonking the other week, and my wife giving me a hard time for buying Coke to try to make it home got me into this......

http://www.wellsphere.com/healthy-livin ... es/1247903

http://www.cbc.ca/smartshift/2010/04/hi ... ewsarchive

The ingredients in Coke in Canada say sugar/glucose-fructose. "Glucose-fructose" is the code word here for HFCS. This apparently means it is an AND/OR situation where cost and availability of the different sweeteners at different bottlers would decide. The rumour is that beet sugar (sucrose) in many areas of canada is cheaper than HFCS, so it is the prevelant sweetner here.

You can get Jones or Boylans cola sweetened with pure cane sugar as another option.

I'm curious with what Chris was saying if the enzymes being used to pre separate the glucose and fructose in HFCS is what causes the effect of higher rates of absorbtion, or if sucrose is similar in effect?

[Brian S]

To all of you--YUP.
All comes down to the old adage--do in racing ONLY what you have tried in training.

My issues with "simple" or complex carbs comes down to gut tolerance. So for me, it is pusing
the 1 gm/kg/hr up to 60 gm carbohydrate/hour, and at lower intensity long efforts such as IM, paying attention to the solubility/osmolarity (essentially concentration) is important too. More than 1 gm/kg/hr for me gets ugly late in the day. Keeping track of intensity, as higher intensity reduces (my) absorptive capacity is also relevant. Again, poor absoprtion secondary to high intensity gets ugly. Lastly I have found that pushing the carbs early, including some solids just for palate and feeling sort of content, allows more flexibility with switching to coke later.

[RyanC]

I know it's annecdotal evidence and a sample of one but nothing I have tried has been more effective at getting me through 200+ k strong than a few judiciously downed colas allong the way. I agree with Josh that flat is better but in the heat I won't argue when I get the fizzy lifting drink variety. I also agree with Brian on individual variation and tolerance; that we need to use what works for us and not change unless we road test before competition.

Ryan

[Dylan J C]

Ive always found a 25-50% coke dilute to be best. The reason HFCS is used in the USA as the primary sweetener for most products is because the government infuses large amounts of money into the corn farmers creating an artificially low price for corn and it's by products http://farm.ewg.org/progdetail.php?fips ... gcode=corn (scroll down a little to find the figures) to the best of my knowledge Canada does not have a similar program.


The national rowing crew use e-load for most of their workouts, it contains dextrose, sucrose and amylopectin in combination with a selection of electrolytes.
http://www.medioncorp.com/the-science-o ... d--p136131

[Chris Watt]

Josh- re: reactive carbonyls in fructose etc- you’re absolutely right that fructose, when it’s unbound from it’s fibrous structure in fruit- is a toxic molecule with nasty long-term consequences. It’s terrible nutrition in the long run- but pretty good fuel in the short run for those rides when it really counts. It’s sort of the high-octane leaded gas of the sport drink world. And whether Canada Coke is sucrose, HFCS or some combo I don’t think makes much difference from a fuelling perspective- sucrose is 50/50 fructose : glucose while HFCS is 55 : 45 fructose to glucose.

Shawn- If you bought the Coke at a Costco in California it may have been from Mexico where sucrose (which is 50/50 glucose:fructose) is used- and apparently it does taste different.

Brian- I agree- more than uptake or absorption it will ultimately come down to tolerance and we all have different abilities to tolerate sweetened sports drinks. If you’re puking it up it doesn’t work as well. But apparently even gastric tolerance is trainable- you can “teach” your stomach to tolerate higher sugar loads. Chrissie Wellington’s CHO intake was 87grams/hour at Ironman Arizona when she set a course record last Nov- which is 50% more than the theoretical maximum rate of absorption of 60g/hr that’s quoted by American College of Sports Medicine.

The central idea is still interesting: if you take two guys who are evenly matched in every way and send them out for a steady-state race over 3-10 hours- the guy who can get deliver the greatest number of CHO molecules as quickly as possible to his working muscles will probably win. But first step is to use a drink with multiple sugar types.

Cheers,
Chris

[sylvan]

Shawn- If you bought the Coke at a Costco in California it may have been from Mexico

That was Adam. Believe me, I understand the confusion.

[shawnc]

Shawn- If you bought the Coke at a Costco in California it may have been from Mexico

That was Adam. Believe me, I understand the confusion.

Ha! Believe me, there's no way one could confuse us now. Adam is in shape.

[Josh.E]

http://www.youtube.com/watch?v=dBnniua6-oM

"sugar - the bitter truth"

Really great video outlining the difference between different types of sugar, and why fructose is so bad for you, aside from glycogen restoration in high performance endurance athletes, which he actually touches on.

If you drink a lot of pop, sports drinks, or juice, watch this video to find out how fructose is converted to VLDL (fat) in the body, why fructose is (directly) what is making you fat, and putting you at risk for diabetes and heart disease.

[leftcoaster]

I finally set an hour and a half aside to watch the video Josh linked about fructose - a bit of an eye opener.

That led me to this - an adv. from a couple of years ago from the corn lobby....

http://www.youtube.com/watch?v=EEbRxTOy ... re=related

But, once you've watched that video (less than a minute long), you have to watch this brilliant take on it. This next one is absolutely great......

http://www.youtube.com/watch?v=mqIpAyHJ ... re=related

- David B

[Quentin]

This one's good too:
http://www.globaltv.com/saturdaynightli ... live/video