x
2024年10月3日

What Is Lactic Acid? Ways to Avoid Its Buildup

  • What Is Lactic Acid? Role in Body and Exercise
  • How Lactic Acid Is Produced
  • How to Prevent Too Much Buildup
  • Risks and Side Effects

Lactic acid (or rather, lactate) is generated in response to demanding physical activities that stress the muscles and demand increased energy. In this way, it serves as a natural response that prompts you to slow down and rest when your muscles are under strain and you are expending a great deal of energy.

The more frequently someone trains, especially if they repeatedly engage in the same intense exercise types, the less they will feel the effects of lactic acid/lactate, such as muscle soreness. In other words, highly trained athletes become accustomed to short periods of elevated lactic acid levels, which means they have enhanced tolerance for its uncomfortable effects.

So, what can you do to perform more like a highly trained athlete? As explained further below, some of the ways to prevent excessive lactic acid buildup – along with lactic acidosis – include gradually increasing exercise intensity, staying well-hydrated, stretching, taking sufficient rest days, and fueling with good nutrition before and after workouts.

What Is Lactic Acid? Role in Body and Exercise

The definition of lactic acid is “an organic acid (C3H6O3) present especially in muscle tissue as a by-product of anaerobic glycolysis, produced in carbohydrate matter usually by bacterial fermentation, and used especially in food and medicine and in industry.”

In other words, it is a natural acid produced in the muscles and red blood cells, particularly during strenuous exercise. This is because lactate can be converted into energy without the need for oxygen.

Aside from being found in the human body, it is also a colorless, syrupy acid formed in fermented/sour milk products like yogurt. Lactic acid fermentation helps create foods that contain beneficial probiotic bacteria.

Lactate vs. lactic acid: What’s the difference?

When it comes to the effects these two substances have on the body, we often hear these terms used interchangeably. However, according to experts, the term “lactic acid” is actually an outdated concept and not well-understood.

Lactate is actually what is produced by your body in response to aerobic exercise, not lactic acid. The difference between the two lies in their chemical compositions.

Lactate is lactic acid that has lost one proton. Lactic acid donates a proton and then becomes its conjugate base, lactate.

Nevertheless, since many people still refer to the effects of lactic acid rather than lactate, that’s how it is mostly described in this article.

What does lactic acid do to the body?

Most people believe that lactic acid in the muscles causes soreness and stiffness.

However, according to an article by Stephen M. Roth in Scientific American, a professor in the Department of Kinesiology at the University of Maryland:

Contrary to popular opinion, lactate or, as it is often called, lactic acid buildup is not responsible for the muscle soreness felt in the days following strenuous exercise. Rather, the production of lactate and other metabolites during extreme exertion results in the burning sensation often felt in active muscles.

Since lactic acid buildup contributes to painful sensations during exercise, it prevents us from overworking and injuring ourselves. It makes us slow down, essentially “forcing a recovery period during which the body clears the lactate and other metabolites.”

How Lactic Acid Is Produced

Lactic acid is produced in higher-than-normal amounts during tough aerobic exercise, as intense physical activity causes the muscles to require more oxygen. When exercise is vigorous enough to outstrip the supply of oxygen that the lungs and heart can provide, lactic acid builds up in the blood.

Lactic acid levels increase in the following situations:

  • During strenuous exercise (this is the most common reason among healthy adults).
  • When someone experiences heart failure, liver failure or pulmonary embolism. For example, the liver normally breaks down lactic acid, but when it is 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 and 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 the body’s oxygen level is low, such as during intense exercise, it breaks down carbohydrates for energy. This process produces lactic acid. Here’s a bit more about why and how this happens:

  • Working muscles generate energy anaerobically from glucose through a process called glycolysis.
  • Glycolysis occurs when glucose is broken down or metabolized into a substance called pyruvate through the Embden-Meyerhof pathway.
  • The body temporarily converts pyruvate into lactate, which allows glucose breakdown and energy production to continue during short bursts of intense exercise.
  • This type of anaerobic energy production can power muscles for about one to three minutes.
  • Lactate levels rise during this time, causing muscles to become more acidic and fatigued, which typically halts such intense activity.
  • Eventually, lactate exits the cells and is transported to the liver, where it is oxidized back to pyruvate and converted to glucose via the Cori cycle.

Is lactic acid harmful to the body?

What does it mean when your lactic acid level is high? High lactic acid resulting from exercise is a normal body reaction, temporary, and for the most part, not harmful.

However, when lactic acid levels rise significantly, this is called lactic acidosis, which is considered life-threatening.

Lactic acidosis occurs when either the body produces too much lactate or when the body cannot clear lactate quickly enough. This can be due to a variety of factors, including:

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

Symptoms of lactic acidosis go beyond normal muscle fatigue. They can include:

  • trouble breathing/rapid breathing
  • excessive sweating
  • abdominal pain
  • nausea
  • vomiting
  • confusion
  • and sometimes coma

Can you die from lactic acidosis? It is possible, although treatment helps control the symptoms from worsening in many cases.

What is a normal lactic acid level?

Your doctor can perform a blood test to determine if your level falls within the normal lactic acid level range. Sometimes, if an infection affecting the brain is suspected to have developed, the amount of lactic acid in spinal fluid may be measured instead of taking a blood sample.

A normal range of lactic acid when measured in venous blood is between 0.5–2.2 milliequivalents per liter (mmol/L, or mEq/L). This is approximately equal to 4.5 to 19.8 milligrams per deciliter (mg/dL).

A normal range 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.

Lactic acid in foods

In addition to the human body, you will also find lactic acid in some fermented foods. Lactic acid bacteria, for example, are present in cultured dairy products (or “sour milk” products) like yogurt and kefir.

This acid is formed through anaerobic respiration carried out by bacterial strains such as Lactobacillus and others.

Lactic acid fermentation, which helps produce probiotic foods, is a metabolic process in which glucose and other six-carbon sugars are converted into cellular energy and the metabolite lactate.

According to Science Direct, “Lactic acid fermentation is the most widespread fermentation process and, depending on the microbes employed, the milk obtained can be classified into thermophilic, probiotic, and mesophilic sour milks.”

How to Prevent Too Much Buildup

What is the quickest way to get rid of lactic acid? Recall that, as mentioned earlier, lactic acid itself is not responsible for “delayed-onset muscle soreness” (or DOMS), which causes severe muscle tenderness after intense workouts.

Soreness, stiffness, and a loss of strength and range of motion usually peak about one to three days after the intense exercise takes place, but the intensity of these symptoms does not depend on how much lactic acid accumulates during exercise.

The exact reason for DOMS occurring is still being researched, but experts believe that an inflammatory-repair response in the muscles is mainly to blame. Muscle cell damage and the elevated release of various metabolites around muscle cells seem to be involved.

You can still work on preventing lactic acid buildup to improve your workout capacity and recovery. Here are tips for keeping lactic acid levels in check:

1. Build Up Exercise Intensity Gradually

If you increase the intensity of your workouts too abruptly, you will experience a lot of muscle fatigue (among other symptoms within a couple of days) as a result.

Give yourself time to gradually build stamina and strength without putting yourself at risk of injury or burnout. You can also prevent overuse injuries by varying the types of workouts you do, the muscles you target, and the intensity of the exercises you perform.

Ideally, divide your weekly workouts into different types: those that are more aerobic in nature (cardio workouts) and those that build strength.

How do you know if you are working at an appropriate intensity? You can monitor your breathing and heart rate.

Practice effective breathing techniques and also consider using a pulse oximeter during exercise. If you feel you are overexerting yourself, slow down and avoid short, shallow breaths, and instead focus on slowing your breathing.

2. Fuel with Proper Nutrition

Ensure that your muscles and organs are fueled with the nutrients your body needs, including adequate complex carbs, proteins, and micronutrients from a variety of whole foods.

The best way to ensure you get enough calories and nutrients to support your fitness level is to eat a variety of foods, including protein sources, healthy fats, fruits, vegetables, high-fiber foods like nuts and seeds, etc.

Foods that provide electrolytes, especially magnesium and potassium, seem to be particularly helpful in managing muscle fatigue during exercise. This means that eating natural sources of these minerals is a good idea for anyone who is active – such as nuts, legumes, leafy greens, potatoes, bananas, broccoli, natural orange juice, and dark cocoa.

Iron is another mineral that is beneficial for fueling your body with oxygen. Iron-rich foods include:

  • liver and organ meats
  • grass-fed beef
  • lentils
  • leafy greens
  • fish
  • black beans
  • nuts

Before a workout and afterward, it can be helpful to eat a source of carbs and protein that your muscles will use for energy. Examples include some fruit or oatmeal with yogurt or cottage cheese or a hard-boiled egg and a slice of sprouted grain bread.

3. Take Rest Days

Your body only has a chance to clear out lactate and other metabolites that have accumulated from tough workouts once you take the time to rest. This is when your muscle tissue is repaired and you “grow back stronger.”

This means muscle recovery is an important part of the fitness puzzle.

Even on rest days, you can do light exercises, such as walking, gentle yoga, or swimming. However, if you are already feeling sore and tired, don’t push yourself to exercise at a high intensity; listen to your body and take at least one or more days off to rest per week.

4. Stretch and Gentle Movement

Stretching before and after a workout supports performance and recovery in several ways, such as by increasing blood flow, improving flexibility, and also mentally enhancing energy/focus.

Try dynamic stretches before exercise that involve moving your body (rather than holding deep stretches), which boosts circulation. Following exercise, you can also use ice packs, get a massage, and take warm baths to increase circulation and help manage the soreness you may be experiencing.

5. Prevent Dehydration

Make sure to drink enough water to prevent symptoms of dehydration and overheating, which can include fatigue, dizziness, and cramps. Aim for at least eight glasses per day or more if you are active or in a very hot climate.

Risks and Side Effects

While high lactic acid levels in response to physical exertion should not pose a risk for otherwise healthy people, lactic acidosis can increase the risk of serious complications and even death in people who are already ill.

Always seek medical help immediately if you develop signs of lactic acidosis. If you have an existing health condition that puts you at risk, discuss intense exercise with your doctor before starting a new program.

Final Thoughts

  • What is lactic acid? It is an organic acid that builds up in the body under certain circumstances, especially during strenuous exercise.
  • What does lactic acid do? It is mainly produced in the muscles and red blood cells and leads to fatigue and soreness. It is formed when the body breaks down carbohydrates to use for energy when oxygen levels are low.
  • Lactic acid in the body is produced by intense exercise, among other causes such as infections, certain diseases, certain medications, and even poisoning.
  • Experts consider the normal lactic acid range to be between 0.5–2.2 milli-equivalents per liter (mmol/L, or mEq/L ) when a venous blood sample is used.
  • Wondering how to get rid of lactic acid? If exercise caused your levels to rise, they should return to normal levels with rest and time. Other ways to manage levels include staying hydrated, stretching, taking sufficient rest days, and fueling with good nutrition.
About Author

Lisa