Sodium the secret weapon

In ancient times, salt was precious. It was traded as the most valued of all commodities, and having a good supply of salt was as close to life insurance as you could get. Age-old aphorisms like "salt of the earth" and "worth your salt" remind us how important salt has always been.




So all the modern-day phobias surrounding salt and sodium seems to present us with a paradox: how could something so vital to survival in one era be considered so deadly in another?

The answer may surprise you. The anti-sodium campaign actually began as a commercial movement to sell different foods and snacks, under the guise of being healthier. Much like the low-fat movement, manufacturers care more about selling products than they do about scientific accuracy.

As soon as the low-sodium content advertisements were shown to create dividends, other food and supplement companies followed suit, to the point where consumers started to believe that low-sodium was good, and salt, in general, was bad. People failed to see that they had been internalizing advertising, not actual scientific information.





For generations, manufacturers have marketed their products by bombarding the public with what ingredients their brand either does or does not have to make their product sell better than the competition's. Like sheep, consumers followed along, buying the "low fat this" or "no sodium that" product, without asking themselves why. In regard to sodium intake, studies are coming in regularly refuting its bad reputation and negative impact on human health, performance, and physiology.




Even after thoGlobalnds of years, human biochemistry and physiology haven't changed much. Although few of us toil under the sweltering sun any more, our bodies' need for electrolytes hasn't changed. In fact, the metabolic needs of high-performance athletes probably most closely resembles the needs of our ancient forefathers, especially in regard to electrolyte ingestion.

Studies in Canada at McGill and McMaster Universities have concluded that unless one has a specific and serious condition that would preclude him from taking in salt, then salt intake will produce no negative health problems, and could actually be health promoting. As a matter of fact, only 10% of hypertension cases have a known cause, and in almost all of these cases, the cause was either genetic or stress related.

For all you short attention span types out there, here is the bottom line: high-performance athletes should not avoid sodium. They should, in fact, ensure that they get adequate amounts of sodium every day to prevent negative metabolic consequences, and to promote maximum performance. That's all. You may be excused.

Everyone else, keep reading

Why Sodium?

Athletes eat for different reasons. Three of the main ones are: 1) as a preventive measure to help stay free from illness 2) for fitness, to ensure optimum energy stores, recuperation, and restoration 3) for bodybuilders especially, to produce a cosmetic effect, i.e. a leaner, harder physique.



If you're an athlete concerned about maximizing your performance (you have no business being an athlete otherwise), you should know that a high-sodium diet fulfills all three of the above. In fact, many problems with athletic performance or sub-maximal athletic performance, even failure to improve, begin when athletes reduce or eliminate sodium from their diets. These ill effects can last for a long time.

While sodium is the primary focus of this article, no nutrient acts on the metabolism by itself. Any discussion on sodium is incomplete without mentioning potassium, and the hormone aldosterone.

As an electrolyte, sodium is the positively charged ion on the outside of the living cell. Cations, anions, and ions exist in an exact balance outside and inside cells, so that a change in the balance of one or more cations or ions will cause a change in other cations and ions in order to maintain cell integrity. Simply put, sodium is responsible for regulating blood volume and blood pressure, although it serves other functions as well.

During a set of high-intensity muscle contraction blood pressure rises. This is a primary response of high-intensity training. During high-performance exercise, the metabolism of the body is better served by a higher blood volume since this translates into better oxygen and nutrient delivery to working cells. Just as importantly, a higher blood volume results in a more efficient removal of fatigue toxins.

A low sodium intake translates into a lower blood volume, and over time this is disastrous to an athlete. Even in healthy people, low blood volume leads to a myriad of problems. Studies at the University of Bonn concluded that a low-sodium diet (and the resulting lower blood volume) was more health-threatening than the hypertension that the low-sodium diet was intended to fix.

For athletes, the effects are even more profound. In a low-sodium situation, the resulting low blood volume delivers less oxygen and nutrients to working muscles, and also allows for greater accumulation of fatigue toxins that might not otherwise occur with a normal or higher blood volume. This results in reduced recuperation and overall weakness. It's the last thing a hard-training athlete wants, but it's what happens when you eliminate crucial electrolytes from your diet.




A low-sodium diet makes the situation even worse in regard to optimum electrolyte metabolism, because potassium is dependent on sodium to be effective for a number of reasons. Potassium's primary responsibilities are the regulation and control of skeletal and cardiac muscles. The vagus nerve, which controls heartbeat, is totally dependent on potassium.

Potassium is the positively charged ion inside of the cell. While its independent functions in the control of muscles have been pointed out, potassium itself is dependent on sodium to maintain cell integrity: the exact balance of cations and ions inside and outside cell walls.

How does potassium get into the muscle cell in the first place? Sodium delivers it. The cell wall is partially permeable to sodium. It takes three molecules of sodium to get one molecule of potassium inside the cell, through a process called "active transport." Sodium is the chaperone, and potassium can't get into the cell without it. Therefore, for optimum cell integrity and optimum potassium delivery, there must be ample sodium present.

This is even more crucial in athletes where electrolyte balance and exchange takes place more rapidly and is more crucial for optimum performance. Also, since the active transport of potassium inside the cell by sodium is metabolically expensive, the activity of sodium-potassium pumps can be adjusted by the thyroid hormones in order to regulate resting caloric expenditure and basal metabolic rate (BMR).

It follows, then, that in a prolonged low-sodium situation, the body may lower BMR in order to control this metabolically expensive function. This spells disaster for the dieting bodybuilder or competing athlete who wants his BMR as high as possible, not lowered by a body compensating for costs it cannot afford to incur.

Even more importantly in this metabolic circumstance is that cell integrity is jeopardized and less potassium can be delivered less often to the cell. This is disastrous for any serious athlete. Obviously, it's the most negative electrolyte situation for a bodybuilder to be in.

Here's how a body could get into such a state of disarray. The primary avenue for the loss of sodium is through sweat glands. No one, except our ancient forefathers, sweats as much as high-performance athletes and bodybuilders.




A typical combination of high-intensity training, interval cardio activity (two sessions per day), and persistent tanning produces an exorbitant loss of sodium through the skin. Combine this with a nearly fanatical effort by bodybuilders and other athletes to exclude sodium from their diets, and you can see how a bad situation can become chronic.

In an emergency situation, the body can only maintain some kind of cell integrity by sending potassium (a positively charged ion) outside the cell to replace the sodium that should be there. The metabolic consequence is weakened cell integrity. Sometimes this causes depolarization between electrically charged ions, and potassium leaving the cell leads to muscle weakness, cramps, listlessness, and lethargy.

Note that it's not the low-calorie diets that produce these physical and psychological symptoms ? it's due to a prolonged lack of sodium intake. The problem can be understood better by discussing the hormone aldosterone. We can also understand why sodium undeservedly gets a bad rap, and how to remedy the situation.

Aldosterone

In a normal metabolic situation, electrolyte balance is delicately maintained by urinary output. The kidneys regulate the concentration of plasma electrolytes of sodium, potassium, and calcium by matching almost exactly the amounts ingested to the amounts excreted. The final amounts of sodium and potassium excreted in the urine are regulated by the needs of the body



Athletes get into trouble when they eliminate sodium from their diet, because their bodies are regularly losing so much of it through sweat and cellular activity. This produces the negative stress response of the release of the hormone aldosterone. Normally, people have low levels of circulating aldosterone. It's a hormone released in response to metabolic or physiological stress.

The release of this hormone serves several functions. The main effect of aldosterone secretion is a reabsorption of sodium through the distal tubules of the kidneys. Thus sodium that normally would have left the body is retained because of the presence of this hormone.

Normal individuals can excrete 30 grams (that's right, 30,000 milligrams) of sodium a day when aldosterone isn't present. This is an average person, not a hard-training athlete. When aldosterone is present, there's no sodium in the urine at all.

Most importantly, water always follows sodium because sodium is positively charged while water is negatively charged. Therefore, the more sodium excreted, the more water leaves the body. But since, in the presence of aldosterone, sodium is reabsorbed and kept in the body, and water follows sodium, water too isn't excreted. The result is water retention.



There's another side to the aldosterone hormonal response, which can also spell disaster for an athlete. Not only does aldosterone cause reabsorption of sodium, but because of this, aldosterone secretion also causes a pronounced excretion of plasma potassium.

Again, in the absence of aldosterone virtually no potassium is excreted in the urine. When aldosterone secretion is maximal, however, there's up to 50 times more potassium excreted than what is initially filtered by the kidneys. A reexamination of the situation reveals that a negative situation exists in such a physiological environment.

First, sodium is reabsorbed. Second, because water follows sodium, there's water retention, which in turn creates an osmotic imbalance. Third, because aldosterone also produces pronounced potassium excretion, the result is further muscular weakness, cramping, performance infringement, and a very flat, tired-looking physique.

This whole misunderstanding of electrolyte function has led to ridiculous myths and misapplications of proper nutrition in the athletic and bodybuilding communities. One of the most bizarre is the practice of taking a potassium chloride (Slow-K) supplement just before a show.

There are two problems with potassium supplementation. First, it's impossible to load potassium inside a cell: cell equilibrium is always maintained in exact ratios. If a certain amount of potassium enters a cell, the identical amount must leave.

The second problem is that an excess of potassium in the blood triggers aldosterone secretion, which leads us back to all of the negative metabolic conditions associated with aldosterone, mentioned earlier. It's a vicious cycle, which can easily be prevented.

Estimating your sodium needs is relatively easy. The rule of thumb is two grams of sodium for each liter of water replacement. Since most athletes are under-hydrated, water needs should also be assessed.

150-pound athletes (both male and female) who train at high intensity levels should drink at least two or three liters of water per day. 200-pound athletes should be drinking a minimum of three to four liters, and athletes over 225 pounds should drink a minimum of four to six liters.



At two grams per liter of fluid replacement, it's obvious that most athletes do not take in nearly enough sodium. For example, a 225-pound athlete would need to ingest between eight and twelve grams of sodium daily. That's right, 8,000 to 12,000 mg a day.

The way to ensure ample sodium intake is through the prodigious use of salty condiments. Sea salt, ketchup, mustard, barbecue sauce, etc. are smart choices to ensure ample amounts of sodium.

However, beware of monosodium glutamate (MSG). Although it's high in sodium, MSG had been shown to be a negative partitioning agent, which means that it may channel nutrients toward fat storage, whether the nutrients contain fat or not. Ingesting MSG can also trigger a catabolic response.
monosodium glutamate





One easy way to ensure adequate sodium intake is by eating pickles on a daily basis. Pickles on average contain about 20 to 30 calories and almost a gram of sodium, so chopping them up into your food makes good sense, as does eating them as a snack.
Pickles



We've all seen hockey players and other athletes taking post game IV drips come playoff time to replace lost electrolytes. Often these IV drips are no more than saline solution; which, as you probably know, is just a fancy name for salt water.

Ordinary salted water-pack tuna is a lot cheaper and easier to find than reduced-sodium tuna. It also tastes better, and is another good source of sodium. While we're on the subject, let me say that bodybuilders have got to get over this "suffering" shtick when it comes to diet. You are allowed to eat food that tastes good, and eating good-tasting food will make it much easier to stay on a prolonged diet.

Don't forget that we're talking about sodium, and not table salt. Table salt is sodium chloride (NaCl; about 40% sodium, and 60% chloride), and many brands of table salt also contain added iodine. This can cause problems for some people's metabolisms, and of course sodium ends up taking the blame. Avoid the issue and use sea salt instead.




Finding foods preserved with sodium phosphate is also useful. Sodium phosphate is one of the best intracellular buffers around, fighting the metabolic acidosis that training can cause. Taking in 3-4 grams of sodium phosphate can increase both aerobic and anaerobic performance.

Athletes who have been trying to avoid sodium for prolonged periods of time and who switch to this high-sodium approach will experience a temporary osmotic imbalance resulting in water retention. This initial effect is only the body's attempt to hold on to the sodium so rarely given to it.

Water retention is temporary, and will dissipate as long as sodium and water intake remain high. The athlete will then notice a higher volume of urinary output, more sweating, the appearance of a leaner, harder physique, and more pumped and full muscles in the gym.
water retention