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June 5, 2008
Personal Best
Real Thought for Food for Long Workouts
By GINA KOLATA

DR. MARK TARNOPOLSKY, a muscle physiology researcher at McMaster University in Canada and a physician, knows all about the exhortations by supplement makers and many nutritionists on what to eat and when to eat it for optimal performance.

The idea is that you are supposed to consume carbohydrates and proteins in a magical four-to-one ratio during endurance events like a long run or bike ride, and right after. The belief is that such nutritional diligence will improve your performance and speed your recovery.

Dr. Tarnopolsky, a 45-year-old trail runner and adventure racer, might be expected to seize upon the nutritional advice. (He won the Ontario trail running series in 2004, 2005 and 2006.)

So might his colleague, Stuart Phillips, a 41-year-old associate professor of kinesiology at McMaster who played rugby for Canada’s national team and now plays it for fun. He also runs, lifts weights and studies nutrition and performance.

In fact, neither researcher regularly uses energy drinks or energy bars. They just drink water, and eat real food. Dr. Tarnopolsky drinks fruit juice; Dr. Phillips eats fruit. And neither one feels a need to ingest a special combination of protein and carbohydrates within a short window of time, a few hours after exercising.

There are grains of truth to the nutrition advice, they and other experts say. But, as so often happens in sports, those grains of truth have been expanded into dictums and have formed the basis for an entire industry in “recovery” products.

They line the shelves of specialty sports stores and supermarkets with names like Accelerade drink, Endurox R4 powder, PowerBar Recovery bar.

“It does seem to me that as a group, athletes are particularly gullible,” said Michael Rennie, a physiologist at the University of Nottingham in England who studies muscle metabolism.

The idea that what you eat and when you eat it will make a big difference in your performance and recovery “is wishful thinking,” said Dr. Rennie, a 61-year-old who was a competitive swimmer and also used to play water polo and rugby.

Here is what is known about proteins, carbohydrates and performance.

During exercise, muscles stop the biochemical reactions used to maintain themselves such as replacing and resynthesizing the proteins needed for day to day activities. It’s not that exercise is damaging your muscles; it’s that they halt the maintenance process until exercise is over.

To do this maintenance, muscles must make protein, and to do so they need to absorb amino acids, the constituent parts of proteins, from the blood. Just after exercise, perhaps for a period no longer than a couple of hours, the protein-building processes of muscle cells are especially receptive to amino acids. That means that if you consume protein, your muscles will use it to quickly replenish proteins that were not made during exercise.

But muscles don’t need much protein, researchers say. Twenty grams is as much as a 176-pound man’s muscles can take. Women, who are smaller and have smaller muscles even compared to their body sizes, need less.

Dr. Rennie said that 10 to 15 grams of protein is probably adequate for any adult. And you don’t need a special drink or energy bar to get it. One egg has 6 grams of protein. Two ounces of chicken has more than 12 grams.

Muscles also need to replenish glycogen, their fuel supply, after a long exercise session — two hours of running, for example. For that they need carbohydrates. Muscle cells are especially efficient in absorbing carbohydrates from the blood just after exercise.

Once again, muscles don’t need much; about one gram of carbohydrate per kilogram of body weight is plenty, Dr. Tarnopolsky said. He weighs 70 kilograms, or 154 pounds, which means he would need 70 grams of carbohydrates, or say, 27 ounces of fruit juice, he said.

Asker Jeukendrup, a 38-year-old 14-time Ironman-distance finisher who is an exercise physiologist and nutritionist at the University of Birmingham in England said the fastest glycogen replacement takes place in the four hours after exercise. Even so, most athletes need not worry.

“Most athletes will have at least 24 hours to recover,” Dr. Jeukendrup said. “We really are talking about a group of extremely elite sports people who train twice a day.” For them, he said, it can be necessary to rapidly replenish muscle glycogen.

The American College of Sports Medicine, in a position paper written by leading experts, reported that athletes who take a day or two to rest or do less-intense workouts between vigorous sessions can pretty much ignore the carbohydrate-timing advice.

The group wrote that for these athletes, “when sufficient carbohydrate is provided over a 24-hour period, the timing of intake does not appear to affect the amount of glycogen stored.”

For protein, it is not clear what the window is. Some studies concluded it was less than two hours, others said three hours, and some failed to find a window at all.

Dr. Rennie and his colleagues, writing in Annual Reviews of Physiology, concluded that “a possible ‘golden period’ ” for getting amino acids into muscles “remains a speculative, no matter how attractive, the concept.”

Although studies by Dr. Jeukendrup and several others have shown that consuming protein after exercise speeds up muscle protein synthesis, no one has shown that that translates into improved performance. The reason, Dr. Jeukendrup said, is that effects on performance, if they occur, won’t happen immediately. They can take 6 to 10 weeks of training. That makes it very hard to design and carry out studies to see if athletes really do improve if they consume protein after they exercise.

“You’d have to control everything, what they do, how they train, and also their carbohydrate and protein intake,” Dr. Jeukendrup said. “Those studies become almost impossible to do.”

As for the special four-to-one ratio of carbohydrates to protein, that, too, is not well established, researchers said. The idea was that you need both carbohydrates and protein consumed together because carbohydrates not only help muscles restore their glycogen but they also elicit the release of insulin. Insulin, the theory goes, helps muscles absorb amino acids.

Insulin may stimulate muscle protein synthesis in young rodents and in human cells grown in petri dishes, Dr. Rennie said. But studies in people have shown convincingly that insulin is not required for protein synthesis in adult human beings; it is amino acids that drive protein synthesis. As yet no convincing evidence exists that a special carbohydrate-to-protein ratio makes a noticeable difference in muscle protein maintenance after exercise. “There is no magic ratio,” Dr. Jeukendrup said.

The American College of Sports Medicine is equally skeptical. “Adding protein does not appreciably enhance glycogen repletion,” its paper states.

“Some studies suggested that adding proteins to carbohydrates during exercise can enhance performance,” Dr. Tarnopolsky said. “Many other studies suggested it didn’t do any good.”

Even if there are effects of protein and carbohydrates, they are not important to most exercisers, these researchers say. Serious triathletes and elite runners, who work out in the morning and at night, need to eat between training sessions. But people who are running a few miles a few days a week don’t need to worry about replenishing their muscles, Dr. Phillips said.

Dr. Rennie agreed. “If you are a superathlete, hundredths of a second matter,” he said. “But most Joes and Janes are just kidding themselves,” he said.

Some, like Dr. Jeukendrup, say they use a commercial protein-energy drink after training hard, for convenience.

Other researchers take their own nutritional advice. Dr. Tarnopolsky has a huge glass of juice, a bagel and a small piece of meat after a two- or three-hour run. Or he might have two large pieces of toast with butter and jam and a couple of scrambled eggs. But no energy bars, no energy drinks.

Dr. Phillips might have an energy bar during a long workout. But ordinarily he does not worry about getting a special carbohydrate-to-protein mix or timing his nutrition when he exercises. Instead, Dr. Phillips said, he simply eats real food at regular meals.
 

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Two things:

*edit*

The article doesn't mention the specialities of these doctors, other than Dr Rennie submits research to a review of physiology. Having the prefix 'Dr' doesn't make you an expert in everything, only your specific field. Otherwise its just like asking someone on the street.


I will agree with the idea that nutrition is far from an exact science and that people who don't compete or have plenty of time for recovery don't need very specialized nutrition.
 

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Game on, b*tches!
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Word. And I'll keep drinking my el-cheapo gatorade and eating some dried or fresh fruit after my workouts.
 

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Sorry, retracted. I was trying to stir the pot and, admittedly, went a little far.

Anyway, I don't think the article is applicable to serious cyclists. The only expert in the field of sports nutrition referenced is Dr Jeukendrup, who's quote is in direct contridiction to recent research he's done ('Superior endurance performance with ingestion of multiple transportable carbohydrates', 'Effects of increasing insulin secretion on acute postexercise blood glucose disposal') and the entire section of his book. His research does suggest, though, that protein consumption is of less importance to recovery than high quality glucose intake.

If you're only exercising to stay in shape, you probably don't need to be stocking up on Endurox, but we already knew that.
 

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“It does seem to me that as a group, athletes are particularly gullible,”

You don't say?

What other athlete would buy $1500 wheels, and not race on them. Or better yet, what other athlete would buy $1500 wheels for a Cat 4 Crit.


Gullible is the polite term. I would use a different word.
 

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Uprwstsdr, thanks for posting this article. Much to often is said that "studies show..." followed by a lot of BS, without mention of how strong (or weak) the evidence is, or how solid was the methodology of the "study".
No more Cytomax for me (that tastes like crap anyway).
 

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Call me a Fred
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In past years the great athletes would eat food and drink alcohol for recovery. Works for me.
 

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haole from the mainland
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Edmund Burke....uh, Hello!

What bugged me about this article was the complete and total omission of Edmund Burke, PhD (RIP). It is my understanding (and I have not delved into his peer-reviewed journal articles), that he didn't pull the 4:1 ratio out of his a$$, but that he actually did studies on recovery.

I think it's fine to report if somebody else's work contradicts Burke's, but to act like the 4:1 ratio just came out of thin air is ludicrous. Certainly, Burke stood to profit from sales of Endurox once it hit the market, but I remember reading articles years before it was available and him giving real food advice such as bagel with peanut butter to get carbs and protein.

Anway, I just found it strange to read an article on recover and not see a single mention of Ed Burke.
 

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haole from the mainland
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If you'll indulge me, I'd like to add another rant about the NYTimes sloppy editing.

Yesterday, I read an article on Tory Burch (Lance's ex to keep kinda on-topic) that made mention of something being akin to JD Salinger 'rising from his grave.' Uh, yes that would be weird as JD Salinger is still alive! Bonehead author and editor.

(I just checked and the reference of rising from the grave has been excised from the on-line version.)
 

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gluteus said:
Uprwstsdr, thanks for posting this article. Much to often is said that "studies show..." followed by a lot of BS, without mention of how strong (or weak) the evidence is, or how solid was the methodology of the "study".
No more Cytomax for me (that tastes like crap anyway).
The problem often is not about how "strong or weak the evidence is" rather it's about how meaningful it is. IOW, just because there is a real difference between x and y, doesn't necessarily mean that it is large enough to be meaningful.
 

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jorgy said:
Edmund Burke....uh, Hello!

What bugged me about this article was the complete and total omission of Edmund Burke, PhD (RIP). It is my understanding (and I have not delved into his peer-reviewed journal articles), that he didn't pull the 4:1 ratio out of his a$$, but that he actually did studies on recovery.
I don't think Burke actually did any of the work showing adding a little protein to a post-workout drink increased glycogen synthesis. He had a relatively meagre publication record and it was mostly around cycling performance not related to nutrition. FWIW, these guys are all pretty big names in the ex. phys. literature, Burke was not, so his ommision isn't surprising despite his visibility within cycling circles.

If I understand correctly, essentially what they are saying is just because adding some protein to a post-workout carb drink enhances glycogen synthesis doesn't mean that translates to better total glycogen repletion by the next workout and improved performance simply because most of us aren't working out intensely enough and often enough without eating adequate carbohydrates in our normal diet to adequately replenish glycogen stores. Nor is there any real good reason to think that endurance athletes need to worry too much about protein for similar reasons. Regardless, I think the main point of the article is you can get that nurtrition via food, there is nothing special about supplements.

Bottom line is basically there isn't any real good reasons to think any of the supplement stuff works any better than real food.
 

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This field is still in the dark ages. Beyond basic results using animal models, what's really known about human performance and nutrition, or even nutrition and health? Pick your favorite supplement/vitamin, like Vitamin E. Does it reduce cardiac risks, does it increase/decrease cancer risk, does it increase/decrease longetivity? What's a 'safe' level of supplementation, does it interact with prescripion medicines (such as anti-cholesterol ones?). Anything known about optimal levels for active individuals? What's known about gender differences?

from the Harvard School of Public Health: "researchers are still writing the book on the optimal intake of vitamin E, and the data are sparse and conflicting."

Bottom-line: saying there's no consensus re nutrition and performance is like shooting fish in a barrel.
 

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I think most know real food vs. suplements isn't the issue. The reason the supliments have a market is because they are easier.

And when was the last time you saw a banana advertised as the on bike energy fuel. Advertisment works.
 

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fleck said:
The reason the supliments have a market is because they are easier.
Yup. Convenience and reliability.

I thought I'd never be a powder and gel guy, but now look at me. I disgust myself.

Most of us "serious" cyclists have a limited amount of time to ride, so we are willing to spend a couple extra dollars to protect our workouts from bonking. I can't buy a box of bananas and keep them in the cupboard for a month, so I use gels and powders instead.
 

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science reporting is notoriously misleading and unreliable -- it's how all of the dogma/myths got propagated in the first instance. And this one doesn't seem to be any different. after reading it, I'm still not sure what I've learned.

one thing that bothers me is that they discuss on the one side multi-workout/day top athletes and on the other Joe runs a couple miles twice a week. Most of us are in between. we're putting in 7-10 hour weeks ("cycling is a sport where you have to work really hard just to suck"). We in the middle -- where does all of this leave us?

one other point. that food works versus supplements is a truism -- it's all food. you supplement curmudgeons, stop crowing. we get it. the potions are still good (a) because they are convenient (b) because they include electrolytes, and (c) because they rehydrate, and nothing here challenges what I think I understand that hydration with food enhances the absorption of both.

I believe that I am as rational and as skeptical as the next guy, but nothing about this persuades me to give up my accelerade/endurox.
 

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bill said:
I believe that I am as rational and as skeptical as the next guy, but nothing about this persuades me to give up my accelerade/endurox.
Nor should it, if you realize you're using it because it is convenient, which I assume you do. I would disagree with some of the above posting though, even food supplements are often marketed as being "better" than regular ol' food rather than just a simple matter of convenience.
 

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fleck said:
I think most know real food vs. suplements isn't the issue. The reason the supliments have a market is because they are easier.

And when was the last time you saw a banana advertised as the on bike energy fuel. Advertisment works.
Bingo!

I use fig newtons and gels on rides...The fig newtons are for the longer rides where there will be stops and the gels are for the shorter butt kicking rides. If I try to eat the figs on those barn burner rides all I end up doing is choking and hacking up a lung...gel is much easier...
 

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Uprwstsdr said:
Dr. Phillips might have an energy bar during a long workout. But ordinarily he does not worry about getting a special carbohydrate-to-protein mix or timing his nutrition when he exercises. Instead, Dr. Phillips said, he simply eats real food at regular meals.
WOW, well good for him! I surely need the energy boost from a gel packet in the last of a tri- or a long circuit race!
 
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