Exercise induced acidosis mitigation and prevention – an outsider’s perspective

By Dr. Keith David Kantor

Abstract

Part One in this series: “The lactate/lactic acid debate – an outsider’s perspective” (1) established that hydrogen proton buildup is the most likely cause of exercise induced acidosis whether or not it is accompanied by an equal buildup of lactate. Although Roberg’s theory is the most promising because it lays out a geometric ratio as established in Part One, this understanding is not necessary for the purposes of this article. The question at hand is what can alleviate the buildup of hydrogen protons or prevent it from happening in the first place?

The physical world is filled with opposite pairs – light and dark, fire and water, or expanding and contracting, for example. Water itself can be seen as a duality. It can be both an acid and a base because it is a polar molecule that has both a negative and a positive side (pole) that do not cancel each other out.

Furthermore, water is in reality made up of two parts, not three even though it contains three atoms – two hydrogen and one oxygen. Water can only be broken down into one hydrogen proton (H+) and one hydroxide ion (OH). The hydroxide ion rarely if ever separates into its constituent atoms. Therefore, hydrogen and hydroxide represent the dual nature of water as both an acid and a base.

Based on the current science as to the nature of both hydrogen and hydroxide as well as the historical science of acid/base theory, this article will seek to establish the theoretical potential of hydroxide to both prevent and alleviate hydrogen proton buildup in the body generally and thereby ease exercise induced acidosis.

This article is not intended to be a detailed analysis of the physiology of muscle cells as they undergo exercise induced acidosis. It will make no distinction between intracellular, intercellular, extracellular, plasma, blood, or any other fluid.
Furthermore, no distinction will be made between bulk water, surface water, or any other limiting factors. This discussion is meant to be an overview assessment, not a technical critique. It is meant to establish the theoretical basis of hydroxide as nature’s most potent acid neutralizer in an aqueous environment and seek to apply this theory to exercise induced acidosis.
NOTE: In this article, hydrogen will be used to refer to the hydrogen proton (H+) without its electron and the term elemental hydrogen will be used to refer to hydrogen with its electron. Hydroxide will be used to refer to the hydroxide ion (OH).

1.0 Water, Hydrogen, and Hydroxide – a Review

Water is made up of three different atoms: two hydrogen and one oxygen but only breaks down into two constituent parts – the hydrogen proton (H+) and the hydroxide ion (OH). In order to understand the relationship between the water molecule and its constituent ions, it is necessary to review some basic chemistry in regards to these two elements and how they combine.

1.1 The Basics

Most of the interactions between atoms take place between the atoms’ electrons. Electrons revolve around the nucleus of an atom in shells. The first shell can hold 2 electrons and the second shell can hold 8. For the purposes of this article it is not necessary to discuss any further shells although they exist. The outer most shell for an atom is called the valance shell whether that is the first shell as in the case of hydrogen or the second shell as is the case with oxygen.
Hydrogen has an atomic number of 1 so at an electrically neutral state it has 1 electron. Optimally hydrogen wants 2 electrons to fill out its valence shell. Although electrically neutral, elemental hydrogen is reactive because it is looking to gain 1 electron to fill out its valance shell. The hydrogen proton is even more reactive because it needs 2 electrons – 1 electron just to return to electroneutrality and another to fill its valence shell.

Oxygen has an atomic number of 8 so at an electrically neutral state it has 8 electrons. There are two in the first shell and 6 in the second or its valence shell. Optimally the valence shell for oxygen wants 8 electrons according to the octet rule. Oxygen is therefore reactive because it is looking to gain 2 electrons to fill out its valance shell.

Atoms form chemical bonds with other atoms in order to fill their valence shell and create stability. In the case of the water molecule this means that the oxygen atom shares 1 electron with each hydrogen atom and each hydrogen atom shares its 1 electron with the oxygen atom. In this way the oxygen atom now has 8 electrons in its valence shell and the hydrogen atoms have 2 electrons in their valence shells. This creates a highly stable molecule.

The bond in which atoms share electrons is called a covalent bond. This is a very strong bond. Covalent bonds come in two kinds, polar and nonpolar. The water molecule forms a polar covalent bond. In simple terms, the electrons shared between the atoms are not shared equally and this creates both a positive and a negative aspect (pole) to the molecule. The reason the electrons are not shared equally is due to the size of the competing nuclei. The oxygen atom has a stronger nucleus because it has more protons than do the hydrogen atoms. This means the electrons are drawn more towards and spend more time around the oxygen nucleus than the hydrogen nuclei. The result is that the oxygen side of the molecule has a slightly negative charge and the hydrogen sides have a slightly positive charge.

This polarity has a further effect on how water molecules interact with each other and with other molecules. The negative sides of a water molecule are attracted to the positive sides of other water molecules and the positive sides are attracted to the negative sides. Each water molecule can therefore form four hydrogen bonds. These bonds are weaker than covalent bonds but are the reason why water has a high surface tension and why it has a high boiling point. These hydrogen bonds also play a major role in how water molecules interact with cations and anions, especially the hydrogen proton and the hydroxide ion.

Polarity also plays a role in the solvent properties of water. Water’s polarity makes it readily available to combine with any other polar molecule or ion. Substances that readily dissolve in water are called hydrophilic. The process by which water breaks down a molecule or ion is called dissociation or dissolution. (2,3,4)

1.2 Hydrogen and Hydroxide

Hydrogen protons are generated in bulk water when a very small percentage of water molecules dissociate and form equal numbers of hydrogen protons and hydroxide ions. The acid dissociation constant of water (KW) at room temperature is 1 × 10-14 or 1 × 10-7 moles H+ protons per liter of water. (5,6) Both formulas are used and express the same thing. The conclusion is that “H2O rarely auto-dissociates and the subsequent ionic products quickly recombine.” (5)

Both the hydrogen proton and the hydroxide ion do not roam freely in water but rather attach themselves to water molecules. Although by convention, the single hydrogen proton is treated as if it is alone this is merely simplification for convenience. When the hydrogen proton combines with a water molecule the result is hydronium (H+ + H2O ? H3O+). This too is a simplification because in reality the hydrogen proton bonds with more than just one water molecule. Stewart’s formula: {H:(H2O)n}+ is the best description of what happens with a hydrogen proton in water. (7)

Hydroxide also combines with water molecules but not quite as freely. This pattern of hydroxide having the same properties as hydrogen but being slightly more constrained will repeat itself. (5,8) A formula similar to Stewart’s expresses how hydroxide does the same thing as hydrogen. Here is the formula: OH(H2O)n. (9) Further study has been done looking at the movement of “proton holes”, aka hydroxide ions, to establish that their movement may be as critical as that of hydrogen protons through the Grotthuss mechanism. (10)

Most of the initial studies were done on hydrogen proton transfers but in the last 20 years or so more focus has been given to hydroxide. Of particular interest is the fact that although both hydrogen and hydroxide move more quickly than other ion species in water, the hydrogen proton is 1.8 times faster than the hydroxide ion. (11) This would make logical sense because only the one proton has to move with hydrogen whereas two atoms, one of which is much larger, have to move with the hydroxide.
Further similarities shared between hydrogen and hydroxide were delineated in Part One and are restated here. (1) In a June 2016 article in Chemical Reviews titled “Protons and Hydroxide Ions in Aqueous Systems”, Agmon et al. (9) stated: “Biological applications reviewed include proton transport along the hydration layer of various membranes and through channel proteins, problems that are at the core of cellular bioenergetics.” Observations made in the article include:

1) Hydrogen bonding in water is inextricably linked with proton (H+) and hydroxide ion (OH) dynamics and structure. From the article: “Despite extensive efforts, achieving detailed, molecular-scale insight has been challenging, partly because the structure and dynamics of protons and hydroxide ions is inextricably linked with the hydrogen bond (HB) dynamics of water, and thus, insight into the former requires a detailed understanding of the latter.”

2) The properties governing H+ and OH differ dramatically from other ion species. From the article: “We begin by briefly describing the founding experiments of the field. These observations strongly suggested that H+ and OH? are unlike other ions in water: e.g., their solvation and transport properties differ dramatically.”

3) The properties of hydrogen bonding observed in bulk water carry over to biological systems. From the article: “In spite of this wide range of different systems, the basic observation of abnormally fast proton transport through the HB network appears to carry over from bulk water to biological systems.”

4) Nuclear Quantum Effects (NQE) influence hydrogen bonding. From the article: “These studies showed, for example, that NQE strengthen strong HBs and weaken the weak HBs, and that in both bulk liquid water and confined water NQE cause proton ‘cluster’ in acidified bulk water.”

5) The properties of H+ and OH are inherently both electronic and nuclear. From the article: “Modeling the proton and hydroxide ions remains challenging also because their physical and chemical properties are inherently quantum mechanical, involving both the electronic and nuclear degrees of freedom. In particular, the importance of quantum fluctuations of the nuclei will be an important issue to consider in future studies.”

Both hydrogen and hydroxide share characteristics that make them unique in an aqueous environment. Much of this can be traced back to the fact that they are in reality the two constituent parts of the water molecule. Figuratively speaking, they share the same DNA as the water molecule because they are in essence part of the water molecule. Any other substance in water is separate from water.

2.0 Acid/Base Theory

The first modern definition of acid/base theory is the Arrhenius theory first put forth in the late 1880s. It describes how acids and bases interact in an aqueous solution (water). Simply put the Arrhenius theory maintains that:

An acid is any substance that produces hydrogen ions in an aqueous solution.
A base is any substance that produces hydroxide ions in an aqueous solution.

Hydrogen ions and hydrogen protons are the same thing and denote a single hydrogen proton with no electron. Acids produce hydrogen protons through dissociation. Most common acids have what is called a dissociation constant: that is the number of protons they readily shed. These acids are also called Arrhenius acids because they fit the definition established at that time.

In most cases Arrhenius acids are one proton donors. Lactic acid would be a prime example. An example of a two proton donor would be oxalic acid. An example of a three proton donor would be citric acid. In all cases the donated protons are connected to water molecules through hydrogen bonding and form hydronium as noted above.

In the realm of base substances, the mineral hydroxides provide perfect examples of Arrhenius bases. Bases are said to ionize because they can either dissociate or dissolve whereas acids almost uniformly dissociate. In both instances, it is the action of water as a universal solvent that sets the ions free. For all practical purposes the concept of dissociation and dissolution have the same effect of freeing ions in an aqueous solution.

Sodium hydroxide and potassium hydroxide both have a one to one ratio between the mineral and the hydroxide ion they are combined with. In water, they dissociate completely where the sodium or potassium forms hydrogen bonds with water molecules as do the corresponding hydroxide ions. Calcium hydroxide, on the other hand, has a two to one ratio with two hydroxide ions attached to one calcium ion. It does not completely dissolve in water but maintains an undissolved amount of calcium hydroxide molecules equal to the number of dissolved calcium ions and hydroxide ions.

The Brønsted–Lowry theory further refined the Arrhenius theory in the early 1920s but it did not change any of the major tenets of the Arrhenius theory. It merely broadened out the application of the principles established beyond just the realm of an aqueous solution. Since the focus of this article is on the aqueous environment it is not necessary to go beyond the Arrhenius theory and complicate matters unnecessarily. (12,13,14)

3.0 Application

According to the Arrhenius theory then, acidity would be defined as the presence of hydrogen ions (protons) in an aqueous solution. This fits with the definition of acidosis in the term exercise induced acidosis. Both the traditional approach to the lactic acid debate and Roberg’s approach recognize that an excess of hydrogen protons in the muscles is the proximate cause of the acidosis. Whether or not there is also an equal amount of lactate does not change this fact. For the traditionalist, the hydrogen is present because of lactic acid but that is irrelevant. It is the fact that the hydrogen is present at all that matters.

Also according to Arrhenius, the polar opposite of the hydrogen ion (proton) would be the hydroxide ion. When the hydrogen proton and the hydroxide ion come into close proximity they will combine and form a new water molecule, returning then to the state in which they are most stable and least reactive. As ions they both remain highly reactive seeking out the opposite charge to return them to electroneutrality.

This then presents an interesting possibility.

HYPOTHESIS:

Free hydroxide ions are the most effective way to combat or prevent acidosis in an aqueous solution and therefore the body.

SUPPORTING EVIDENCE:

Self-ionization of Water

As discussed early water can auto-dissociate or self-ionize. This is important for two reasons: it shows the versatility of the water molecule and also the strength of the bonds that hold the water molecule together. In many biological processes hydrogen protons act as catalysts and this self-ionization can provide those protons. Second, under normal circumstances the water molecule will stay together for a very high percentage of time. Although the water molecule can act as an acid it is not a promiscuous proton donor like most acids. This also means that the attraction between the hydrogen proton and hydroxide ion will be strong when they are anywhere in the vicinity of each other. They will seek to return to their natural state as part of the water molecule whenever possible.

Special Characteristics Shared by Hydrogen and Hydroxide in Water

As delineated above, hydrogen and hydroxide act differently in an aqueous solution than any other ions because they are in essence part of water. Of particular importance is the fact that their solvation and transport properties are distinct to them alone. They move more quickly and more freely than other ions can. There also appears to be a difference in the way hydrogen bonds play between them and water molecules. This difference is both electrical and nuclear with quantum considerations. Last and most importantly, the characteristics of hydrogen and hydroxide found in bulk water translate to biological systems. (9) What does this mean? It means that in the same way hydrogen and hydroxide move in and interact with bulk water, is the same way they move and interact in the body. Whether or not hydroxide can penetrate the cell itself is not known. What is known is that hydrogen interacts with the cell and hydroxide can and will interact with the cell. If free form hydroxide can be introduced to the body then it is highly probable that if it does not enter the cell itself, it will be found in the aqueous environment that the cell exists in. If excess hydrogen is in the vicinity the two will find each other to combine and form a new water molecule.

Buffering

The bicarbonate buffering system in the body seeks to maintain pH by countering the offending substance with an opposite charge which neutralizes it but does not remove or eliminate it. (13) This is the same process that allows minerals and electrolytes found in alkaline waters to buffer acidity. Again, the positive charge is neutralized by a negative charge but the hydrogen proton(s) remain(s).

Free form hydroxide does not buffer, rather it eliminates the acid (hydrogen proton) completely by combining with it and forming a new water molecule. The problem disappears and hydration occurs.

If excess hydrogen is being transported by the bicarbonate buffering system in the blood and free form hydroxide is introduced into the blood, the two will find each other and form a new water molecule. This will then free up the resources that were being used to buffer the hydrogen so they can be used elsewhere in the body.

Lactate

The role of lactate in the body is far greater than that of a dead-end metabolite. (116,17,18,19,20,21,22) Whether it enters the cell as part of lactic acid or is used by the cell/body to buffer the hydrogen proton does not matter. The fact is, if lactate, hydrogen, and hydroxide are all present, the hydrogen proton and hydroxide ion are going to combine to form a water molecule thus freeing up the lactate for the body to use elsewhere.

Overall Acidic Load

Free form hydroxide introduced to the body through ingestion can and will lower the acidic load in the blood and by so doing lower the acidic load for the entire body. Whether or not hydroxide can also go from the blood into the different cells of the body is up for debate but by lowering the acidic load in the blood it allows the body to use its resources to lower acidity elsewhere if it is not able to enter these areas. As noted above, it is highly probable that free from hydroxide can move freely throughout the body since the body is an aqueous environment just as hydroxide moves freely in bulk water.

4.0 The Source

Hydroxide is currently available in various forms. Water ionizing machines use minerals and electro-magnetism to create hydroxide ions. Sodium, potassium, calcium, and magnesium are the most common minerals used. Most alkaline waters also use this same technology to infuse their waters with negative ions (hydroxide). Each one attempts to claim some sort of proprietary technology but they all follow the same principles and end up with the same result.

The reason these machines and these waters use the minerals listed is because the hydroxide ion is not normally found by itself in nature, rather it is attached to another element, most commonly a metal (mineral) to form a base molecule or compound. As stated by Arrhenius, hydroxide is the strongest base and polar opposite of hydrogen.

There are two groups of metal (mineral) hydroxides: alkali and alkaline earth. Alkali metal hydroxides are monovalent and alkaline earth metal hydroxides are divalent. This means in an alkali metal hydroxide for every one mineral ion there is only one corresponding hydroxide ion. In an alkaline earth metal hydroxide there are two hydroxide ions for every mineral ion. The result is that alkaline earth metal hydroxides have twice as many hydroxide ions as the alkali metal hydroxides.

The next issue is how to set the hydroxide ion free in an aqueous solution so that it can be utilized. As noted earlier, the term ionization is used to describe this process because it can come about either through dissociation or dissolution. The concepts of dissociation and dissolution have the same effect of freeing ions in an aqueous solution. According to Arrhenius, free hydroxide ions are the most important factor in determining alkalinity in an aqueous solution. Alkalinity by definition measures the quantitative ability of a base to neutralize an acid.

Potassium hydroxide and sodium hydroxide are the strongest in terms of alkalinity in an aqueous solution among the alkali metals. Both completely dissociate in water. This means that the mineral ions (sodium or potassium) and the hydroxide ions break apart and spheres of hydration surround each ion. Potassium hydroxide is slightly stronger than sodium hydroxide.
Calcium hydroxide and magnesium hydroxide are the strongest in terms of alkalinity in an aqueous solution among the alkaline earth metals. Calcium hydroxide does not have the same level of solvation as potassium hydroxide or sodium hydroxide because it is only relatively soluble where the other two completely dissociate. To reach a saturated solution of calcium hydroxide, an equal amount of undissolved calcium hydroxide must be present in relation to the calcium ions and hydroxide ions freely floating in the solution. So for every two free hydroxide ions there is one corresponding calcium ion and one corresponding calcium hydroxide molecule.

The net result, however, would be comparable to that which is attained with both potassium hydroxide and sodium hydroxide. If you had 10 sodium hydroxide molecules or 10 potassium hydroxide molecules you would end up with 10 free hydroxide ions and 10 sodium ions or potassium ions. If you had 10 calcium hydroxide ions you would end up with 10 free hydroxide ions, 5 calcium ions, and 5 calcium hydroxide molecules. In each case you end up with the same amount of free hydroxide.

Magnesium hydroxide, on the other hand, has an even weaker alkalinity because it has low solubility and does not dissociate very well. Even though this is true, magnesium hydroxide is still used as a common component of antacids because even with its weaker properties it is still effective.

Potassium hydroxide, sodium hydroxide, calcium hydroxide, and magnesium hydroxide are all strong bases with strong alkalinity in an aqueous solution. Magnesium hydroxide is by far the weakest of the four because of its solubility and dissociation issues. The other three each produce effective levels of free hydroxides in an aqueous solution.

5.0 Conclusion

The main cause of exercise induced acidosis is hydrogen proton build up whether or not there is a commensurate lactate build up. Based on the characteristics shared by hydrogen and hydroxide and based on foundational acid/base theory, hydroxide provides the best and most effective solution to the hydrogen build up that leads to exercise induced acidosis. Current research into the role of both hydrogen and hydroxide in an aqueous solution can be readily applied to the body. When seen in this light, no other ion has the same potential that hydroxide has to counter the effects of hydrogen. If hydroxide is able to be used then the results are far more transformational than typical buffering because instead of just cancelling the positive charge with a negative one, the combining of hydrogen and hydroxide eliminates the acidity completely and replaces it with a neutral water molecule. Thus, the acidity disappears with the added benefit of extra hydration. Hydroxide rich water that has as much free form hydroxide ions as possible with as little minerals as possible is the best source of hydroxide ions.

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