News On Beet Juice, Running & Evolution, Saturated Fat & Cardiovascular Disease

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I’m behind on posting and I’m trying to catch up.  There’s been a lot of interesting information to read in various publications.  If you’re a runner (and probably any other sort of endurance athlete) you definitely need to see some of this.  If you’re listening to government guidelines on saturated fat, then definitely look at the last article.

Beet juice for endurance

A number of articles have appeared lately about beet juice and its benefits for endurance athletes.  Never miss a beet is from Outside Magazine.  The article discusses two studies from Exeter University in England that demonstrated performance benefits for cyclists.  Here are the important details.  (Emphasis added is mine.):

… In 2009, a small study done at England’s Exeter University caught the attention of the fitness world. Researchers discovered that competitive cyclists who drank half a liter (about 16 ounces) of beet juice right before they got on their bikes were able to ride 16 percent longer—a massive gain in a sport where only a few percentage points of improvement can be the difference between first place and fifteenth.

Last June, a larger Exeter study backed up this rather unusual protocol: cyclists who drank half a liter of beet juice for six days were 11 seconds faster over a 2.5-mile course and 45 seconds faster over a 10-mile course. The reason: more oxygen was getting to the athletes’ muscles, thanks to molecules in the juice called nitrates. “The oxygen cost of exercising at a given speed is basically fixed,” says Andrew Jones, a professor of applied physiology at Exeter and lead author of both studies. “Only nitrate ingestion appears to improve efficiency. These effects cannot be achieved by any other known means, including training.”

It works like this: Our bodies convert nitrates into nitric oxide, a gas that causes blood vessels to relax and widen, by a process known as vasodilation. This allows more oxygen-rich blood to flow through the body—and the more oxygen reaches the muscles, the longer they’re able to perform at high intensity. Athletes have tried to trigger vasodilation with various banned substances, including hypertension drugs and erectile-dysfunction medication, for years. It now appears that simply consuming large amounts of vegetables that are high in nitrates, such as spinach, carrots, radishes, and beets—the last of which pack the biggest punch, a whopping 310 grams per 16 ounces of juice—can offer the same performance boost.

The article also discusses beta-alanine supplementation.  I haven’t used beta-alanine but recently I have been playing around with eating and juicing beets.  (I don’t juice a whole beet.  I combine about ¼ beet with other fruits and vegetables.)  I pretty much will never say that one thing causes one other thing, but since I’ve been consuming more beets, my workouts have felt really good.  Also, getting up early has been easier.  Again, I can’t say this is the only factor but I see no reason not to continue gobbling a few beets through the week.

One odd thing about beets is that they color some of your bodily excretions, meaning you may see a red tint in the toilet soon after eating or drinking beet juice.  It was kind of alarming the first time I noticed it.  Turns out it’s normal.  Despite this weird side effect, I’m giving beets a thumbs-up.

Evolution, distance running, and a controversial title for an article

Other articles have discussed the idea that human evolution and distance running are intimately intertwined.  A recent article from Slate Magazine suggests the same thing.  If nothing else, All men can’t jump: Why nearly every sport except long-distance running is fundamentally absurd sounds like fun reading.  From our Achilles tendons, to our teeth, brains, our ability to dissipate heat , gait mechanics, and even the “runner’s high,” the article suggests that we are uniquely and powerfully suited to “persistence hunting,” that is chasing down prey until it’s tired.  I think it’s an interesting theory, though I wonder if some day scientists will ruminate over the connection between our thumbs, evolution, and video games or text messaging.

Overhydration

It’s summer.  It’s hot.  We still run, bike, hike, walk, etc.  How much should we drink?  How often? Do we need to weigh ourselves before and after exercise?  Does dehydration lead directly to heatstroke? Furthermore, have you ever heard of hyponatremia, or what happens to you when you drink too much water.  (FYI, drinking too much can be far more deadly than being dehydrated.)

The issue of hydration is a pendulum that still swings around and there is confusion.  Many of us are growing gills for the amount of water we’re drinking, but this high consumption of water throughout the day seems a fairly recent thing.  Do we really need all this consumption?  How did we manage before plastic bottles?  (Watch an episode of Mad Men and you’ll see the only water anyone drank came from melted ice cubes in their cocktail.  How’d we get out of the 1950s under those circumstances?)

For more information, read the Outside Magazine article Tim Noakes on the serious problem of overhydration in endurance sports. (Why listen to Dr. Noakes?  He’s a leading exercise scientist and he’s just recently written a 439-page book called  Waterlogged: The Serious Problem of Overhydration in Endurance Sports.  He’s a very well informed guy.  All runners should read his superb book Lore of Running.)

The article covers some interesting information including how hunter/gatherers run a lot during a hunt but don’t drink until they’ve caught their prey, the history and marketing of sports drinks, and why a bit of dehydration is nothing to fear.

Here’s some background on why we think we need to drink so much when exercising.  (Emphasis is mine.):

When did we start drinking more water?

Well, the sports drink industry was involved. In 1969 a great American physiologist, David Costill, started new studies. Gatorade was just getting into the market, and he went to them and said, Listen, you produce this product, do you know if it works? Is it of any value? He said, I’ll do the studies and let’s see if it works. His focus was to try and raise money to fund his laboratory. He did the first study where he had people like Amby Burfoot—who writes the foreword for the book and won the 1968 Boston Marathon—not drinking anything. Costill had them run when they drank up to 1.2 liters per hour on the treadmill, and [then run] when they didn’t drink. When they did drink, he showed their body temperatures were much lower and he presumed that was better. But if you ask Amby Burfoot, he said he felt much better when he ran without drinking. Costill assumed then that drinking was good for you, although the study hadn’t really shown that because it wasn’t a performance trial, and all the runners found when they didn’t drink was that there were no problems associated with not drinking. The American College of Sports Medicine asked David Costill to write the first drinking guidelines, which he did in 1975. He said that runners should drink regularly during exercise, which is pretty good advice.

Then, what I discovered, which was really eye-opening, was that a single individual working for the U.S. military decided that water was a tactical weapon. That if the military could be encouraged to drink more during maneuvers, they’d have less heat stroke and less illness and they’d be more productive and could be better soldiers. It was purely his idea. It had no scientific basis at all. Two years later he published a paper supposedly saying that if the US soldiers drank 1.9 liters per hour [64 ounces] when they were exercising in the heat they would perform much better. There was utterly no concrete evidence that that was true. The problem was, his advice was embraced by the U.S. Military. They changed their drinking guidelines to say that you should now drink 1.9 liters per hour. The same people who drew up those guidelines were then invited by the American College of Sports Medicine to get involved with drawing up guidelines for runners.

The essential information first and foremost 1) let thirst be your guide, 2) over drinking is bad, and 3) anything short of severe dehydration won’t kill you.

Evidence on saturated fat and cardiovascular disease

Finally, I’ve mentioned before that perhaps we shouldn’t be as afraid of fat–particularly saturated fat–to the degree that we’ve been told.  We’ve got a little more evidence in that direction.  Saturated fat and cardiovascular disease: the discrepancy between the scientific literature and dietary advice is a recent study from the Netherlands.

Researchers evaluated three reports from leading U.S. and European dietary advisory committees with results of studies on dietary fat and cardiovascular disease as they were presented in the referenced articles.  (These committees are the sort that tell us to eat less fat for fear of contracting such ailments as heart disease.)  The findings indicate that the advice given by the committees doesn’t reflect the evidence.  The concluding statement of the abstract of the study says, “Results and conclusions about saturated fat intake in relation to cardiovascular disease, from leading advisory committees, do not reflect the available scientific literature.”  So again, perhaps we should reconsider our view of nasty old saturated fat.

Hydration

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It’s summer and it’s hot.  Seems like the ideal time to write about hydration.  First, I’ll comment New York Times Health Section features the piece titled In Summer’s Heat, Watch What You Drink.  The article has two main points.  The first point concerns our fluid intake and the idea that we likely aren’t drinking enough to replace water lost to perspiration.  The second point deals with high-calorie drinks and the fact that it’s easy to consume too many calories in our quest to hydrate ourselves.  This post regards the first point.

Regarding fluid intake, the article suggests that a) our thirst is a poor guide for fluid intake and b) a quenched thirst is equally unreliable as a guide.  The suggestion is that we should multiply our weight in pounds by 0.08 and then drink that number’s worth of eight-ounce cups of water daily.  Sounds a little complicated to me.  Prior to the advent of mathematics, how did early homo sapiens drink enough to survive?

(The above mentioned formula is almost as complicated as this one.  If you’d like to further complicate your drinking habits, try the test described here.)

In the recent past, we were advised to drink eight glasses of water a day.  No one is entirely sure where this advice came from.  Then we were given formulas like the above mentioned methods to figure out how much fluid we needed to consume.  There was and still is widespread fear that a little dehydration would certainly cause cramps, delirium, and possibly death.  Like the Times article, much of the popular advice told us our thirst wasn’t a good guide–that to wait until we were thirsty to drink was to wait too late.

In recent years though we’ve seen new hydration guidelines.  These guidelines are much simpler, more instinctive and easier to follow.

A list of the old vs. new rules of hydration can be found on Active.com.  The best new rule in my view is to drink according to your thirst.  Excellent.  That’s what thirst is for right?  A signal that it’s time to drink.  The article states,

“The idea that thirst comes too late is a marketing ploy of the sports-drink industry,” says Tim Noakes, M.D., a professor of sport and exercise science at the University of Cape Town, South Africa. While thirst is not a perfect indicator of hydration status, it does appear to be a good indicator of the optimal drinking rate during exercise, according to Noakes. “The answer is just drink as your thirst dictates.”

Another new rule is to drink to slow dehydration rather than drink to completely prevent dehydration.  Studies show that the effort to drink to completely prevent dehydration is nearly impossible and uncomfortable.  Slight dehydration is not a health threat despite many popular fear to the contrary.   To that point, overhydration or hyponatrimia is far more dangerous.

(One easy hydration check you can use regards urine color, as advocated at Ask the Dietitian.  Dark urine means you need more water.  Light yellow means your adequately hydrated.)

Next, sports drinks are superior to plain water if your activity lasts more than one hour.  Sports drinks contain important electrolytes such as sodium, calcium, magnesium, potassium, and phosphate as well as carbohydrates for fuel.

Some sports drinks such as Accelerade and Hammer’s Perpetuem contain protein.  At least one study suggests that consuming small amounts of protein during a workout boosts performance.  Be careful though.  Some people (like my wife) experience gastrointestinal turmoil when they consume such drinks.

Next new rule regards caffeine.  Previously, we were told that caffeinated drinks would dehydrate us.  Now we’re told that isn’t quite the case.  Caffeine can be a powerful ergogenic aid that may aid performance but it doesn’t seem to be inhibit adequate hydration.  (Alcohol on the other hand definitely promotes dehydration.)

Finally, cold fluid is best to drink when it’s hot.  (Similar to thirst, this seems instinctively obvious right?)  It was once suggested that warmer water emptied out of the stomach faster but that’s no longer regarded as true.  Nor does cold water promote cramping.

In conclusion, don’t complicate things.  Drink as much (cold) fluid as you feel is appropriate.  Drink a sports drink if you’re out in the heat for over an hour.  You may want to experiment with protein and/or caffeine.

Product Review: Gatorade G Natural and G2 Natural

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I’ll admit I’m a little bit excited in that someone at Gatorade reads my blog and sent me a couple of their new products to test.  (I almost feel like a real journalist!)  Gatorade G Natural and G2 Natural are two sports drinks that Gatorade is marketing as a natural alternative to their regular sports drinks.  Both drinks are part of Gatorade’s Perform line of drinks.  This means they’re designed to be drunk during a workout or competition.  (Pre-competition/workout and post-competition/workout drinks are also available.)  G Natural is a full-calorie drink with 50 calories per serving while G2 Natural is a low-calorie drink with 2o calories per serving.  The G Natural I got was orange flavored.  G2 Natural was berry flavored.

I drank the G Natural on a tough, quick bike ride up Lookout Mountain in Golden, CO.  It was warm and the road was steep.  A sports drink was definitely in order.  I drank the G2 Natural after a five mile run.  I found it refreshing and adequate to the task.

Flavor is probably the most important factor as to whether or not someone likes a sports drink.  (Research has shown people will drink more if a drink is flavored as opposed to an unflavored drink like water.)  My personal preference is for a light-flavored drink but this is a rare find among sports drinks.  I found the G Natural flavor to be a bit strong, but it was nothing severe.  I’d be perfectly happy to find this drink at rest stops during a bike tour or a running event.

Overall, I think this new Gatorade product is just fine and if you’re a fan of Gatorade then you’ll probably like these drinks.  What has me thinking though is to what degree is this new product actually “natural?”  To me, calling something natural implies that it is a minimally processed product.  In my mind, natural foods should contain no engineered chemicals or food additives that I can’t pronounce or produce in my kitchen.  So what’s in Gatorade Natural?  (Specifically, we’ll look at what’s in the orange flavored drink.)

First is water.  Nothing remarkable there.  Second is sucrose.  What is that?  A sugar naturally found in plants but it can also be manufactured in a factory or lab.  I don’t know where Gatorade gets its sucrose.  Second is dextrose, AKA glucose.  Glucose occurs naturally but commercial glucose is derived from plants, most commonly from corn–but this isn’t corn syrup.

Erythritol is next.  (Ever cook up a batch of erythritol?)  This is a sugar alcohol.  It’s sweet but has almost no calories, therefore it’s often used as a sweetener in nutritional supplements and soft drinks like Gatorade.  It’s derived via fermentation of glucose.  This sugar alcohol tends to be easier on the digestive tract than other sugar alcohols like maltitol, sorbitol and xylitol.  Erythritol also doesn’t affect blood-sugar levels thus making it fairly safe for diabetics.  In my view, this is not a natural substance.  That said, it sounds like good stuff to me.  From the way it’s described, erythritol is a fairly benign sweetener and I have no problem using it on a consistent basis.

Next is citric acid.  That’s in a lot of things.  It’s used as a food flavoring and preservative.  It’s also found naturally, often in citrus fruits.  (Guess what else.  If you buy a large enough quantity of it, the authorities may suspect you of terrorist activity because of citric acid’s role in the production of HMTD, a very powerful explosive.)

The always popular natural flavor is next on the list.  The Code of Federal Regulations defines as natural flavoring as such:

“The term natural flavor or natural flavoring means the essential oil, oleoresin, essence or extractive, protein hydrolysate, distillate, or any product of roasting, heating or enzymolysis, which contains the flavoring constituents derived from a spice, fruit or fruit juice, vegetable or vegetable juice, edible yeast, herb, bark, bud, root, leaf or similar plant material, meat, seafood, poultry, eggs, dairy products, or fermentation products thereof, whose significant function in food is flavoring rather than nutritional. Natural flavors include the natural essence or extractives obtained from plants listed in §§182.10, 182.20, 182.40, and 182.50 and part 184 of this chapter, and the substances listed in §172.510 of this chapter.”

So is natural flavor natural?  You be the judge.

Sea salt follows natural flavor on the ingredient list.  I’d call this some fairly natural stuff.  It comes by way of evaporating sea water thus leaving sea salt.

Sodium citrate is next on the list.  (One of three types of sodium citrate, trisodium citrate is the only food additive.)  This is a tart flavoring and preservative used in various drinks as well as an anticoagulant in order to help preserve blood in blood banks..  It’s a relative of citric acid.  How is it produced?  If you’ve got a chemistry background, it shouldn’t be too tough.  Can you find it in what most of us would call “nature?”  Unlikely.

Finally we’ve got beta carotene (for color).  (Can’t have a natural drink without color right?)  Well, it’s fairly natural stuff.  It’s what gives carrots and other orange veggies and fruits their orange color.  (Wouldn’t it be ironic if the beta carotene in orange flavored Gatorade Natural came from carrots instead of oranges?)  Beta carotene is quite possibly very healthy for you so long as it’s consumed in it’s natural state; that is as a whole food along with the thousands of other compounds found in carrots, oranges, pumpkins, sweet potato, orange peppers, etc.  In contrast, if you’re a smoker and you consume enough beta carotene in isolation, your chances of lung cancer go up.

What’s my point here?  The term “natural” can be applied to almost any food.  There are no specific regulations concerning its use.  We’re starting to learn that highly processed foods are unhealthy for us.  Organic foods are becoming more popular and many of us recognize the health benefits of eating non-processed or minimally processed foods (i.e. stuff that’s simply pulled out of the ground or yanked off a tree branch.)  Thus there is profit to be made by way of foods we might generally consider natural.  Is Gatorade Natural actually natural?  It depends on your definition.  Almost anything on earth or in the universe might be considered natural.  (Supernatural probably isn’t the correct term for  Gatorade Natural either.)  Does it contain some naturally found substances?  Yes.  Does it also contain some highly processed substances?  Also yes.

Am I calling Gatorade Natural a bad or unhealthy product?  No.  I truly have no idea of the overall health effects of Gatorade Natural.  I personally have no fear of consuming the product.  It may well be the ideal thirst quenching fuel for many athletes.  At the same time, it’s not quite what I consider to be a natural product.