Phun Physiology: Branched-Chain Amino Acids

What are branched-chain amino acids (BCAAs), the claims being made about them as they relate to endurance athletic performance, and the reality?

If the following commercial claims do not provide sufficient incentive for you to want to try BCAAs, arouse a little intellectual curiosity, or make you wonder whether your cycling buddies haven’t intentionally withheld vital information from you in order to retard your development and prevent you from assuming your rightful place on the podium, don’t worry. There’s more!

Ever since the 1970s, when it was first thought that BCAAs were legal performance enhancers, there has been much interest in these three naturally occurring essential amino acids on the part of nutritionists and athletes, not to mention commercial purveyors.

In fact, just this week, I received two different e-mails from a well-known nutrition-supplement chain store touting the alleged benefits of BCAAs. Here is a portion of the claim for one of the products.

Branch Chain Amino Acids (BCAA) – leucine, isoleucine and valine – are critically important for stimulating muscle protein synthesis, reducing protein breakdown and preserving muscle glycogen stores.* The body uses these essential amino acids as fuel during exercise.*

The asterisks of course alert us to the following claim . . .

*These statements have not been evaluated by the Food and Drug Administration.
Another BCAA product marketed by the same retailer comes with a slightly different set of claims, also accompanied with an asterisk:

BCAA's [sic] enter your bloodstream and attach directly to muscle where they repair damaged muscle tissue. This process helps ensure maximum muscle recovery and growth!*
I then searched for the claims by a competitor regarding its BCAA formulation:

· Decreases perception of fatigue and increase cognitive performance.
· Helps build, maintain, and repair lean muscle mass.
In all, I’ve been able to compile a list of ten (10) alleged benefits of BCAAs by commercial vendors that I wish to discuss. The claims include: 1) performance enhancement as a third energy source after carbohydrates and lipids, 2) glycogen preservation, 3) faster muscle recovery, 4) reduced muscle damage, 5) reduced muscle soreness post-exercise, 6) reduced mental fatigue, 7) increased cognitive capacity post-exercise, 8) decreased muscle wasting, 9) performance enhancement in heat, at altitude, and in other situations, and 10) immune system support.

Before getting down to the business of addressing each of these claims vis-à-vis the scientific literature, I shall provide some background information on BCAAs and amino acids in general.

No doubt humans require protein. Dietary protein is digested enzymatically by our body into smaller molecules known as amino acids, which in turn are immediately absorbed by the small intestine. After entering each of our body’s cells, the amino acids are then used as building blocks for the manufacture of tens of thousands of different human proteins, including muscle tissue, which is largely protein.

Twenty types of amino acids are required by the body. Our cells have the ability to synthesize all but eight of the 20 amino acids. The eight we cannot synthesize are called “essential” amino acids, because they can only be obtained from our diet. The BCAAs—valine, leucine, and isoleucine—are three of the eight essential amino acids the body requires but cannot synthesize.

Why are BCAAs important to athletes? It is true that BCAAs, particularly leucine, play an important role in muscle synthesis. Not only do BCAAs take their place alongside other amino acids as raw materials in protein synthesis, but leucine acts uniquely as a signaling molecule that initiates post-exercise protein synthesis.

The importance of ingesting leucine post-exercise becomes abundantly clear when we learn that its intracellular concentration diminishes as a direct function of the duration of endurance exercise. The longer we exercise the less leucine there is to trigger post-exercise muscle protein synthesis.

Where do BCAAs get their name? All amino acids have the same general structure:
Note that the central carbon (C) atom has four bonds depicted as lines radiating out like points on a compass to four different groups called “side chains.” Three of the side chains are invariable. The variable fourth side chain (in green) determines the particular amino acid, in this case glycine. The BCAAs get their name from the fact that the variable fourth side chain is branched.
Locate the branched side chain located on the “south” side of each of the three BCAAs. Imagine valine as an aerodynamic Tour rider on a road bike, leucine as an upright randonneur, and isoleucine as a trick rider doing a wheelie.

Now it is time to unveil my list of ten alleged benefits of BCAAs followed by critical commentary:

1. Since the 1970s, assertions keep popping up that BCAAs act as fuel during exercise in addition to carbohydrate and fat. To the contrary, BCAAs are not performance enhancing in the sense that they provide a significant or “third” energy source for endurance athletes. Thus, the commercial claim quoted above that, “The body uses these essential amino acids as fuel during exercise,” is highly misleading. While it is true that amino acid breakdown during exercise may result in some energy production, it is trivially true.

According to one expert, a Tour de France cyclist consumes only twice the amount of BCAAs during competition as a sedentary individual. Compare this to both carbohydrate and fat consumption, where detailed studies have shown that

the oxidation of BCAAs only increases 2- to 3-fold during exercise, whereas the oxidation of carbohydrate and fat increases 10- to 20-fold.

Moreover, the same researcher argues that when athletes fuel primarily with carbohydrates as they normally do, BCAA oxidation slows.

[C]arbohydrate ingestion during exercise can prevent the increase in BCAA oxidation. BCAAs, therefore, do not seem to play a major role as a fuel during exercise, and from this point of view, the supplementation of BCAAs during exercise is unnecessary.
Yet another research team concludes that

Leucine oxidation increases in proportion to energy expenditure, but the total contribution of BCAA to fuel provision during exercise is minor and insufficient to increase dietary protein requirements.
2. The claim made by the first commercial provider above, that BCAAs play a role in “preserving muscle glycogen stores” is also misleading, again, because it is only trivially true.

We just noted above that during exercise the relationship between BCAAs and carbohydrates is the reverse of this last claim; that is, carbohydrate ingestion during exercise slows BCAA oxidation. But since BCAAs are gradually depleted as a function of exercise duration, it is not altogether clear how they could preserve muscle glycogen as claimed.

While it is true that BCAAs do cause glucose synthesis and subsequent gluconeogenesis (glycogen synthesis), it is difficult to understand the significance of these events in the grand scheme of muscle energetics in light of each of the previous comments.

3. There is good evidence that BCAAs aid muscle recovery. In fact, the mechanism by which leucine is thought to initiate post-exercise protein synthesis is well known.

And although researchers tell us that

endurance exercise reduces the rate of muscle protein synthesis in proportion to the duration and intensity of activity,
they remind us that the post-exercise ingestion of a combination of leucine and carbohydrate allows maximum stimulation of protein synthesis.

4. BCAAs do seem to reduce muscle damage that results from exercise, according to many experts, one of which notes:

BCAA supplementation before and after exercise has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis.
5. In some situations, BCAAs may reduce post-exercise muscle soreness and fatigue. One group of researchers found that delayed-onset muscle soreness (DOMS) that results from resistance exercise is attenuated by BCAA supplementation.

BCAA supplementation prior to squat exercise decreased DOMS and muscle fatigue occurring for a few days after exercise.

6. There seems to be good evidence that BCAAs can reduce mental fatigue, and that

7. BCAAs improve cognitive function post-exercise. First a note on what is meant by physical fatigue.

There are two components of physical fatigue that affect endurance athletic performance, that is, the ability to maintain power output. These are the peripheral and central (mental) components.

Peripheral factors affecting physical fatigue include failure in neuromuscular signaling, waste buildup, and muscle energy store depletion, for example.

Central (mental) factors of physical fatigue are less well known. Central fatigue however can be demonstrated by the fact that willful maximal muscle effort is less than that which can be achieved when the motor nerve to the same muscle is electrically stimulated.

According to a well respected study by a Swedish researcher,

[W]hen BCAAs were supplied to human subjects during a standardized cycle ergometer exercise their ratings of perceived exertion and mental fatigue were reduced, and, during a competitive 30-km cross country race, their performance on different cognitive tasks was improved after the race.
Part of the reason researchers believe that BCAAs reduce mental fatigue is that they seem to have cornered a mechanism for its action. In short, it is thought that BCAAs block the uptake of a particular serotonin precursor (the amino acid tryptophan) in the brain. Serotonin (5-HT) is thought to play a role in causing central fatigue.

8. BCAAs are currently being studied as a way to slow muscle wasting in the elderly. Although this has little to do with endurance athletes in their prime, muscle wasting known as sarcopenia is a direct function of aging processes. Medical researchers assert:

[L]ong-term essential amino acid supplementation may be a useful tool for the prevention and treatment of sarcopenia, particularly if excess leucine is provided in the supplement.
9. Finally, the claim that arises from time to time regarding the alleged performance enhancing nature of BCAAs. Although some have suggested that BCAAs help athletes perform at moderate levels (40% VO2max) in the heat (34° C/ 93.2° F), the evidence is equivocal. So too is the suggestion that athletes perform better at altitude after ingesting BCAAs.

Generally speaking, no study so far suggesting a performance enhancing effect of BCAAs for endurance athletes has been able to withstand criticisms concerning methodology. One team of researchers reports that

A number of research groups examined whether BCAA supplementation might have a beneficial effect on endurance performance, but the results are inconsistent.

10. Although controversial, at least one study suggests that BCAAs decrease the negative effects of long-term strenuous exercise on the immune response. While exercise generally bolsters the immune response, long-term strenuous exercise as a stressor can have the opposite effect. Whether BCAAs benefit those who over train is currently debatable.

In sum, there are indeed great benefits that BCAAs provide for endurance athletes, in particular, benefits relating to muscle recovery, maintenance, and growth, but also cognitive function and reduced physical fatigue caused by mental factors. On the other hand, claims regarding muscle energetics and increased performance are generally viewed by most experts as dubious at best.

What about the toxicity of BCAAs? Most athletes are aware of the problems associated with ingesting too much protein: kidney damage, arteriosclerosis, and dehydration, for example. The same prohibitions apply to BCAAs, although there don’t seem to be any problems inherent to them. One researcher notes that

Acute intake of BCAA supplements of about 10-30 g/d seem to be without ill effect.
Finally, one group of researchers assures us that

There are no reports concerning BCAA toxicity in relation to exercise and sports.

What about cost and availability of BCAAs? One can easily compare costs of supplements on the one hand with natural foods on the other. One researcher notes
a typical BCAA supplement sold in tablet form contains 100 mg of valine, 50 mg isoleucine, and 100 mg leucine. A chicken breast (100 g) contains ~470 mg valine, 375 mg isoleucine, and 656 mg leucine, the equivalent of about 7 BCAA tablets.

Plant products also contain BCAAs. The previous researcher reports that in fact,

One quarter cup of peanuts (60 g) contains even more BCAA and is equivalent to 11 tablets.

Endurance athletes need more protein than non-athletes but not as much as body builders. Most of us probably get as much protein as we need. The amount of protein we consume on a daily basis can easily be calculated and compared with recommended amounts.

The best time to consume complete proteins (along with carbohydrates to ensure maximal protein synthesis) is immediately after exercise, when the machinery of protein synthesis is literally waiting in the wings for raw material, a pool of exogenous amino acids. Complete proteins contain all 20 amino acids, including ample amounts of BCAAs. Examples include beans and rice or food of animal origin.

A little protein ingested during exercise may also help with sundry physiological processes like hydration given the fact that there are amino acid transporters whose activity aids intestinal water absorption, thereby aiding quick and maximal hydration.

Regarding the purchase of BCAAs, one can obtain powders of complete proteins that contain sufficient amounts of BCAAs at grocery stores or online and which generally cost much less than commercially supplied BCAA caplets.

The amounts of BCAAs in everyday foods, including plants material, can be found at web sites like this. Some of the highest levels of leucine are found, for example, in soy protein and spirulina, a sea weed. The optimal ratios of BCAAs occur naturally in food.

As parting advice, I wouldn’t become too anxious about BCAAs as long as I knew that I was getting sufficient amounts of (complete) protein in my diet. Researchers note that BCAAs consumed in excess are simply excreted by the body.

We’ll get a meal as soon as we finish, but for now just grab a burger or a pack of peanuts and . . .

Let’s ride!

Phun Physiology: Don't Blame the Turkey for that Thanksgiving Post-Dinner Nap

Ever planned to do a little cycling Thanksgiving day, but just couldn’t get going after one of those family sanctioned annual food eating contests?

You feel like lying around on the couch. The fireplace glow puts your eyelids at ease. Lions and Cowboys run around on TV. Lost in reverie, you count drumsticks on John Madden’s Thanksgiving bird.

An involuntary twitch and you awaken. Did you say, “Bicycle ride?”

Forget it. You might as well enjoy another round of turkey alongside cranberries hemmed in with a wedge of dressing topped off with a slice of sweet potato pie before lapsing once more into a food coma.

We’ve all heard that turkey makes you sleepy. Some claim it’s an enzyme. Others say it’s tryptophan. Either way, I’m sorry to inform you that it’s nothing more than just another urban legend.

It’s true that L-tryptophan, an essential amino acid, is found in turkey. It’s also true that tryptophan is a precursor both to serotonin, a brain chemical that helps us relax, and to melatonin, a brain chemical that makes us sleepy. Moreover, it’s true that tryptophan can be purchased over the counter as a sleep aid.

But personally, between you and me, the only straightforward indication I’ve ever found connecting tryptophan with sleep are the glassy looks people get when they’re presented the chemical pathway of tryptophan.

Take it from my friend, specialist and spokesbird, Tommy Tee, here, who explains the real cause of sleep following that Thanksgiving dinner: overindulgence.

“In the first place,” Tommy Tee explains, “tryptophan is no more concentrated in turkey than it is in chicken, ham, hamburger, or cheese for that matter. And none of them are blamed for sleep.”

Tommy Tee adds, “You got no right to pick on us turkeys!”

I’ll pick it up from here. Tommy Tee gets way too agitated on this subject.

Second, as a sleep aid, tryptophan must be taken in pure form on an empty stomach. This ensures that it is the only amino acid available to the brain. This is not the case when we eat meat which normally contains 20 different amino acids all vying for brain access. Tryptophan’s somnambulant effect decreases when we eat a slice of turkey compared to popping a tryptophan pill.

On the other hand (or, drumstick, if you prefer), let’s take a closer look at Tommy Tee’s overindulgence hypothesis as the cause of after dinner sluggishness. Thanksgiving dinner consists not only of turkey but an endless provision of carbohydrates and lipids.

Carbohydrates play a huge role in promoting sleep. In fact, without carbohydrates, tryptophan cannot make us sleepy. Carbohydrates—the starches and sugars from dressing, sweet potato pie, cranberries, rolls, and so on—cause a gush of insulin. Insulin in turn induces muscles to absorb amino acids from the blood with the notable exception of tryptophan. The result is a relative increase in blood tryptophan, which can now exert greater influence on the brain. In fact, the more carbohydrates we consume, the greater tryptophan’s influence on the brain.

What about fat? What would Thanksgiving dinner be without dressing or collard green drippings? Fats take even longer to digest than carbohydrates or proteins. In the process, they divert even more blood for digestion and away from the brain dulling our senses.

What about seconds? The more helpings we consume, the more blood we need for digestion, again, leaving less for the brain.

Did I mention sipping on an adult beverage, which acts as a nervous system depressant?

So, while it is true that tryptophan promotes sleep, a dinner consisting solely of turkey cannot make us sleepy. We could just as easily invite sleep by eating ham, hamburger, or chicken as long as we pile our plates high with plenty of carbohydrates and fats. Any holiday dinner will do!

What is my advice for cyclists this Thanksgiving?

Personally, I wouldn’t think of missing Thanksgiving dinner. Nor am I going to hold back on the goodies. My buddy, Tommy Tee, and I are going to stick to our game plan. “Gobble, gobble!” he says.

Think of it this way: Thanksgiving dinner is a wonderful opportunity to carb load in anticipation of December’s R-12. After all, most of us should be awake by then!

Phun Physiology: Post-Exercise Consumption of Caffeine-Carbohydrate Combo Speeds Muscle Glycogen Re-synthesis, by Dean Furbish

There is something new in our understanding of the effects of caffeine on athletic performance!

Caffeine intake after exercise in addition to carbohydrate consumption boosts the rate of muscle glycogen re-synthesis, thereby speeding recovery, according to a team of Australian researchers. Muscles store energy in the form of glycogen for future use. The application of this knowledge would provide endurance athletes who compete on successive days an obvious advantage.

The article which appeared in the Journal of Applied Physiology in June 2008 indicates that subjects who consumed both carbohydrates and caffeine after exhaustive exercise rebuilt 66% more new muscle glycogen than subjects who consumed just carbohydrate and no caffeine. The dramatic effect was seen after only four hours of recovery.

Our readers know that writers here at RTP have unabashedly extolled the virtues of caffeine. We’ve known for some time based on hundreds of studies that caffeine can boost athletic performance. Thus the pre-ride cup of coffee and the caffeinated gels and other fixes during the ride. Now, thanks to our Aussie friends, we have one more reason to continue celebrating caffeine even after the ride. And that ain’t no hill of beans!

As with most scientific studies, there are some caveats. Obviously, some people do not tolerate caffeine. Additionally, the dosage—8mg caffeine/kg body wt—amounts to the equivalent of five cups of coffee for an “average-size” person, according to the lead researcher. The question is whether similar results can be achieved with less caffeine, something the researchers will be addressing.

One strength of the study was the use of trained athletes as subjects. Moreover, an underlying mechanism was suggested, a calcium-dependent enzyme which speeds glucose transport into muscle. For those interested in the actual study, the reference is: Pederson, D.J. (May 8, 2008). High rates of muscle glycogen resynthesis after exhaustive exercise when carbohydrate is co-ingested with caffeine. J Appl Physiol.

Dean's Nutrition Advice: Round 4

N.C. Randonneur Dean Furbish, who teaches physiology at a local college, has contributed three recent columns on cycling and nutrition. That has generated several questions from readers. Here's the latest, with Dean's answer.

hspatz said...
I told my doctor of problems I was having in the heat and he said not to ride so much in the heat (not a helpful answer.) I put my symptom set into Google and it was a perfect match to hyponatremia and I informed my doctor of such. He copied off 7 pages about hyponatremia from a Dr. Burton Rose that said that exercise induced hyponatremia comes from excess water consumption and the proof came from a Boston Marathon where many hyponatremic runners had weight gain from water, as opposed to a New Zealand marathon with fewer water stations where there was no hyponatremia. Dr. Rose's advice was to drink only when thirsty and to avoid weight gain by drinking less. From my experience, the advise should be to increase electrolytes and not worry about drinking too much. If the electrolytes are OK the athlete will urinate excess fluids instead of holding on to them. It seems to me that Dr. Rose's advice will lead to dehydration and not fix the hyponatremia. What do you think?
May 28, 2008 5:31 PM

Dean's response:

HS is correct to increase water intake supplemented with electrolytes to stave off hyponatremia and maintain performance. The only remaining question regarding intake is: “How much?” While “more is better,” there are limits to water and electrolyte intake. To my knowledge, no expert on the subject recommends consuming more than one loses during an endurance event. Moreover, one school of thought questions whether one should even try to replace all that is lost. The reason is that there are limits regarding how much water, food, and electrolytes can be absorbed during an endurance event. Fortunately, estimates of water and sodium loss during endurance events abound, giving athletes a place to start in calculating replenishment needs. I’ve provided one such link below.

With that said, I feel it worthwhile to expound on HS’s situation. Given the competing schools of thought HS has dug up, an explanation of why I believe the rider’s proposed strategy is correct may benefit other riders.

Let’s start with something with which everyone agrees. Excessive water intake can dilute blood sodium, resulting in hyponatremia (i.e., low blood sodium). Hyponatremia should be avoided. According to current thought, hyponatremia leads to nausea, vomiting, muscular cramping, and cerebral edema (i.e., brain swelling). HS points out two strategies for avoiding hyponatremia. The first strategy would be to drink less water, the position ascribed by HS to the good doctor Rose. The second strategy would be to supplement water intake with electrolytes, HS’s position.

The first strategy of drinking less water to avoid hyponatremia would be good advice for athletes who are, in fact, drinking excessive amounts. But what is excessive? According to HS, the good doctor argues that athletes should be guided by thirst so as not to drink too much. But is this a workable strategy? I shall argue that it is not. While the strategy prevents hyponatremia, it ultimately leads to dehydration and underperformance.

Our sense of thirst is not a sufficient indicator of water need. Although the brain’s “thirst center” monitors blood-sodium directly, it is slow to send the thirst signal. If this weren’t bad enough, the thirst signal shuts off prematurely, that is, after we’ve taken only a few gulps of water! This is completely counter to the needs of endurance athletes. Elaine Marieb (2007, p. 1040) in Human Anatomy & Physiology writes:

As effective as thirst is, it is not always a reliable indicator of need. This is particularly true during athletic events, when thirst can be satisfied long before sufficient liquids have been drunk to maintain the body in top form.

My advice for endurance athletes regarding hydration is as follows:

First, begin hydrating at least a day in advance of an endurance contest. Urination is not necessarily a good indicator of one’s hydration state, however. The kidneys will immediately begin to flush extra water from the blood plasma before it has had a chance to move into both extra- and intracellular spaces, resulting in complete hydration. Hydration takes time, given the passive, slow processes of osmosis and diffusion. The athlete should not consume excessive electrolytes during this hydration period.

Second, taper the usage of diuretics such as caffeine and alcohol during this hydration period. Caffeine causes the body to excrete sodium, thus upsetting both fluid and electrolyte balance. This does not include the pre-event cup of coffee, which, by many accounts, may boost performance. Some athletes are even able to consume caffeine during events without any adverse (i.e., diuretic) consequences.

Third, begin drinking fluid at the start of an endurance event, long before the onset of thirst, and continue drinking throughout the event enough water for replenishment.

Fourth, in order to avoid hyponatremia, make sure to supplement water intake with electrolyes. Food provides some electrolytes. One should be aware that some popular sports drinks do not supply all the electrolytes one needs and can lead to hyponatremia. The possibility of hyponatremia increases in the late stages of endurance events when athletes begin diluting sports drinks due to a heightened ability to taste sugar and the perception such drinks are too sweet.

In his blog entry on hyponatremia, Douglas Stoddard, a physician—with a specialty in sports medicine—and an endurance athlete, himself, makes this very point when he quotes an authoritative source on sweat loss, Dr. Burton Rose’s (1994, p. 656) Clinical Physiology of Acid-Base and Electrolyte Disorders,

. . . these losses are almost entirely replaced by . . . solutions (including Gatorade) that have a much lower salt concentration. The net effect is water retention and, in some cases, symptomatic hyponatremia, with a fall in plasma sodium concentration . . .

But simply adding more sodium to one’s water or sports drink may not be the answer endurance athletes seek. Although a major player in fluid and electrolyte balance, sodium is not the only electrolyte important for good health. Overloading on sodium may cause a shift in the hormonal controls that maintain proper water and electrolyte balance during an endurance event to competing mechanisms that focus more on sodium overload.

Electrolytes: Part 3

In the past two weeks, physiologist and randonneur Dean Furbish has been enlightening us on the use of electrolytes. This week, he tackles a couple follow-up questions.

Anonymous said...
Dean, what specific advice would you give on using electrolytes in hot weather? How many & how often?

Thanks, Mike

May 14, 2008 7:59 AM
Anonymous said...
Regarding electrolytes, I've been a fan of Eduralytes by Hammer Nutrition for their balance of several ions and minerals. At first I was taking their recommended dosage of 3 per hour or so but have found that I can get by on a lot less - like one every couple hours+. Given your argument regarding food/water/electrolyte combo for best absorption, seems like I would want to bump that up a bit for best overall energy and performance. (If I were biking that is!)
Regards,
Rich B

In answering Mike’s and Rich’s questions, I shall focus on a single electrolyte product named by Rich: endurolyte capsules from Hammer Nutrition.

Mike’s question is one that every cyclist wants answered. That is, now that we have the theory behind electrolytes, how do we put it to practical use?

The answer to the question of how many endurolytes and how often they should be consumed can be found in a table in an article, Suggested amounts of Endurolytes to consider, on the Hammer Nutrition (HN) website:

It should be noted that these are only guidelines. This is because there are several factors affecting electrolyte replenishment.

Mike’s question implies that hot weather may be a factor in determining electrolyte need. He’s right. Because we sweat more in hot weather in order to cool our body, we lose more electrolytes. In this case, we need to increase electrolyte consumption.

Rich mentions that he seems to have been able to get by on fewer endurolytes than the apparent recommended dosage. This is actually true for certain conditions. HN quotes a study, which found that athletes lose less fluids and electrolytes if they are well-conditioned or if they have engaged in event-specific training in terms of both duration and intensity.

What are specific factors that are known to affect electrolyte needs? In addition to fitness level and body weight, HN states that “weather conditions, acclimatization level, and biological predisposition all greatly affect electrolyte depletion and the need for replenishment.”

As it turns out, because of all of the factors that must be considered, it is difficult to make other than general recommendations regarding electrolyte replenishment. However, one should consider increasing electrolyte consumption during an event particularly if he or she is a large athlete, less than optimally conditioned, or if it is hot.

In the end, it falls on each cyclist to try to determine personal electrolyte consumption needs. This is made easier armed with the understanding that the type of food one eats while cycling and the factors listed above should be considered. This calls for the cyclist to engage in some experimentation, preferably, during training rides.

A note of caution: as with food and water consumption, it is possible to overdo electrolyte consumption, particularly if one eats a lot of sodium (table salt). The problem is that the processes that deal with sodium overload interfere with those required for maintaining normal electrolyte balances. Moreover, the people at HN remind us that since it is not possible to absorb the same amounts of food, water, or electrolytes that one uses during an endurance event, attempting to do so is futile.

Update on Electrolytes By Dean

In a Q&A last week, our friend Dean discussed the use of electrolytes on long rides. That prompted this question from Branson:

So I shouldn't be drinking straight water on a long ride- everything should have a little sports drink mixed in?

Here's Dean's response:

Regarding electrolytes, let me start by saying that you are obviously doing something right, given your long-distance riding successes. Any deviations from something that already works should be tested first on training rides.

Drinking straight water on rides lasting longer than two hours is fine if one eats real food, which generally supplies not only the right minerals but the right amounts. Cyclists normally obtain food on brevets, since meal breaks are often customary. Sufficient alternatives to food (for mineral content) include special energy powders and electrolyte tablets. On the other hand, sports bars, gels, and drinks do not always supply either the full array of minerals long-distance cyclists require or the amounts/ratios required for easy assimilation.

In addition to the essential minerals they provide, food and specially formulated energy powders have the added benefit of supplying easily assimilable calories. Such nutriment has the added benefit of promoting the burning of stored fat, which accounts for more than half the energy used by distance cyclists.

On long rides, the body unavoidably uses protein as yet another energy source. If a cyclist’s on-the-bike diet includes some protein, then the body not only has another readily available energy source but is less likely to scavenge muscle.

If a cyclist eats a disproportionately high amount of simple sugar(s), then the desirable fat-burning process may be hindered. Also, a huge meal forces the digestive system to compete with muscles for blood.

In conclusion, although it is oftentimes necessary to discuss electrolytes irrespective of hydration and food requirements, in devising a suitable strategy for replenishing electroylytes, it is helpful to view the latter as part of an integrated food and hydration plan.

Oasis: Not Just A Band

oasis (ō′ā•səs): (geography) An isolated fertile area, usually limited in extent and surrounded by desert, and marked by vegetation and a water supply.

I know an oasis when I see one. They have nothing to do with the water supply. They’re all about food.

An oasis is that general store with the grill in the back. The roadside stand or the freestanding restaurant which appears, like some genetic freak of nature, on a winding side road, miles from any village or town.

It’s a marvel that the establishment survives the change in seasons. One slow weekend could threaten its very existence. But there it is. Wrapped in the ethereal perfume of crisp bacon. Luring the famished cyclist with the siren song of the $4.95 Breakfast Platter. The $5.99 Cheeseburger Special.

I came across my first oasis on a winter cycling tour from North Carolina to the Deep Frozen South. The farther we rode into Dixie, the colder it got. I feared for the thermometers and the citrus crops. I feared for my toes.

The year was 1975. We’d spent a night on the frozen tundra of Alabama, shaking in flimsy tents and absurdly inadequate sleeping bags. Sweet Home Alabama. Where was Lynyrd when you needed em? Probably with their boots up on a roaring wood stove.

In the morning, after knocking a crust of frost from our bags and bikes, we got rolling. The only thing worse than the cold was the hunger.

Just five miles later, parked at a crossroads, we hit one of those places. I don’t recall the name, but to this day that simple meal of eggs, biscuits, grits and slab bacon ranks on my list of Top Five Culinary Delights. I’m certain the Big Guy in the Sky was lobbing the biscuits down to the fry cook. They were not of this Earth.

Every table had a mason jar filled with homemade blackberry jam. I loaded each biscuit down like a pack mule until it fairly collapsed from the weight of its syrupy cargo.

I left there with a warm belly and a new take on life.

Perhaps we only get to see the light on the road to Damascus once. But I’ve come close a few other times.

Last year on BMB, as I labored through the interminable hills between Ludlow and Brattleboro, I came upon a family dairy farm that operated a small ice cream stand.

For 15 minutes or so, I forgot all about my sore hand and my sorer legs. I was just the kid with a double scoop of vanilla, my only pressing worry whether I’d finish before the ice cream began its inevitable melt through the waffle cone.

The ice cream story brings me round to the point of this entry: the Mapleview Farm Store just north of Chapel Hill and Carrboro.

We’re talking about a store smack dab in the middle of nowhere -- and just one cow pasture away from the herd that contributes sweet cream to the cause.

Chapel Hill and Carrboro are arguably the epicenter of cycling in the Tar Heel state. Mapleview has helped clinch that reputation.

When Orange County cyclists are done for the day, chances are they’ll stop in for a shake or sundae, sit in one of a dozen rockers on Mapleview’s front porch and debate just how sweet life is.

Good ice cream knows no season. This picture shows a group of randonneurs enjoying a frozen treat following an icy December century in 2005.

As if the ice cream weren’t enough, there’s another reason to support Mapleview.

At a time when the land surrounding urban areas is being carved up into subdivision after subdivision, Mapleview stands as an oasis of enlightened land planning and conservation. In 1995, the owners of the farm granted a conservation easement to the Triangle Land Conservancy to insure continuation of the farming and dairy operations, and to help preserve the area’s open spaces.

Wouldn’t you know it? There’s a solid cycling connection here. Kate Dixon, the former head of TLC, helped make the Mapleview easement a reality. A cyclist herself, she has ridden across the state in the annual fall ride, Cycle North Carolina. Her husband Dan is a RUSA member and most recently completed the Morrisville 300K.