Lactic Acid

8/2/2021

Watching the Olympic competition, it never ceases to amaze me to see humans pushing themselves beyond their physical and mental limits to achieve a dream of competing in these international events and to give every ounce of determination to reach the pinnacle of their performance (maybe with the exception of the U.S. Men’s Basketball team!).

And with this physical determination, we witness athletes collapse and succumb to complete exhaustion. Experts in the field of human physiology have been studying methods to improve our endurance and physical limitations, focusing on one of the main reasons that cause humans to hit a wall and finally capitulate to the pain brought on as they strive to pass their physical boundaries. That is, lactic acid/lactate.  Hope you enjoy this weeks’ Safety Message!

Watch out for each other and…have a SAFE DAY!

As the world turns its attention to Olympic competition, I thought that a discussion of lactic acid would be appropriate. After all, it is lactic acid that is the chemical factor that causes our muscles to burn and ache as we push ourselves to our physical limits and beyond.  The most obvious example of seeing Olympic athletes push themselves to physical extremes – I would imagine – is the marathon, where the distance is 26.2 miles. It is not uncommon to see competitors limp and crawl across the finish line in complete exhaustion.  Typically, there are ambulances and health care workers standing by, ready to take a runner, completely fatigued, to a local hospital for emergency treatment.     

Lactic acid is an organic acid (aka carboxylic acid) with the chemical formula C₃H₆O₃ that is present in muscle tissue. Physically, it is described as a colorless, syrupy (i.e. highly viscous) liquid. Not only is lactic acid produced in our bodies, but it is a fermentation product formed in fermented/sour milk products such as yogurt and is a major ingredient in foods that contain healthy probiotic bacteria (live microorganisms that have been identified to have certain health benefits).

In other words, it’s a natural acid produced in nature as well as in our bodies; specifically, the muscles and red blood cells, and is produce in abundance during strenuous exercise.

As it turns out, experts in the field of kinesiology have been trying to educate the public that it is lactate and not lactic acid (lactate being the conjugate base of lactic acid, where a proton/hydrogen atom is removed from the carboxylic acid) that causes soreness in our muscles¹. And it is the production of lactate and other metabolites during extreme exertion that causes the burning sensation often felt in active muscles. And when this happens, our ability to continue exercising decreases as the pain caused due to lactate build-up can be excruciating.

This pain caused by lactate build-up is a warning mechanism or protection as it prevents us from overworking and injuring ourselves. It causes us to slow down, essentially forcing a recovery period in which the body clears the lactate and other metabolites from our bodies.

Lactate is produced during these high intensity periods of physical demand when our muscles need more oxygen. This, in turn, places a high demand on our lungs and heart to provide additional oxygen through our aerobic breathing process. And when our lungs and heart cannot keep up with this demand, lactate begins to build up in the blood. At this point, the high lactate concentrations in our blood is distributed throughout our bodies, including our muscles, which then cause that extreme pain which is designed to force us to slow down.

The exact reason for the pain that is associated with exercising is not fully understood, although experts have noted that extreme exercise results in an inflammatory-repair response, which leads to swelling and soreness referred to as “delayed-onset muscle soreness” or DOMS.  As a result, it is quite common to use anti-inflammatory medications to reduce muscle swelling. And while anti-inflammatory drugs do appear to reduce the muscle soreness, they may slow the ability of the muscle to repair the damage, which may have negative consequences for muscle function in the weeks following a strenuous event¹.

It has been postulated that the reason some athletes that have received notoriety for superior performance and breaking Olympic records have a condition where a build-up of lactate is diminished; thus, decreasing physical pain and allowing them to continue pushing themselves competitively.    

Besides strenuous exercise, lactate levels can increase due to the following situations:

• When someone experiences heart failure, liver failure or pulmonary embolism. For example, the liver normally breaks down lactic acid, but when it comes damaged or fails this process becomes impaired.
• When a severe infection develops, such as sepsis.
• When someone takes the medication called metformin (usually given to manage diabetes).
• In response to severe dehydration and/or overheating.
• Due to conditions that affect the blood, such as severe anemia or leukemia.
• Due to carbon monoxide poisoning, alcohol poisoning or poisoning caused by consumption of chemicals like antifreeze (ethylene glycol).
• Due to nutrient deficiencies, including low thiamine/B vitamins.

When lactate levels rise significantly, this is called lactic acidosis, which can be life-threatening. This happens when either the body makes too much lactate or when the body can’t clear lactate quickly enough. This can be due to many different factors, some of which include:

• use of medications
• very intense exercise
• respiratory failure
• heart disease
• anemia

A normal range of lactate when measured in venous blood is between 4.5 to 19.8 milligrams per deciliter (mg/dL) or , when measured in arterial blood, is between 0.5–1.6 mmol/L. Arterial measurements are usually more accurate, but they are more difficult to perform than regular blood tests using blood from a vein.

While fatal conditions from lactate build-up may be extreme, an increase in lactate concentration can cause other, less severe health concerns and include such conditions as breathing/rapid breathing, excessive sweating, abdominal pain, nausea, vomiting, and confusion.

For many weekend workout warriors and full-time athletic competitors, a build-up of lactate can present more than an inconvenience; often, forcing those that aspire to maintain a certain level of physical fitness to take a break from their workout regimen. Yet, there are several things that can be done to help prevent lactate build-up. These include:

1. Build Up Exercise Intensity Gradually
2. Fuel with Proper Nutrition
3. Take rest days
4. Stretching before and after a workout supports performance and recovery in several ways, such as by increasing blood flow, improving flexibility and also by mentally improving energy/focus.
5. Prevent dehydration

Exercise is king. Nutrition is queen. Put them together and you’ve got a kingdom – Jack LaLanne

1-Stephen Roth, M. January 23, 2006, “Why Does Lactic Acid Build Up in Muscles? And Why Does It Cause Soreness?” Scientific American