Lactic acid, or lactate, is produced when your body needs more energy, especially during demanding physical activities. This process is a natural response that prompts you to slow down and rest when your muscles are under stress and you’re exerting significant energy. Consistent training, particularly with repetitive intense exercises, can reduce the impact of lactic acid, such as muscle soreness. Highly trained athletes adapt to these short periods of elevated lactic acid levels, increasing their tolerance to its discomforting effects.
To perform more like a seasoned athlete, you can gradually increase exercise intensity, maintain hydration, stretch regularly, incorporate sufficient rest days, and fuel your body with proper nutrition before and after workouts. Let’s delve into What Foods Are High In Lactic Acid and how they play a role in our bodies.
Lactic Acid: Definition, Role, and Production
Lactic acid is an organic acid present in muscle tissue, produced as a byproduct of anaerobic glycolysis. This process occurs in carbohydrate matter, often through bacterial fermentation, and is utilized in food, medicine, and industry.
Essentially, lactic acid is a natural acid produced in muscles and red blood cells, notably during strenuous exercise, enabling energy conversion without oxygen. Besides its presence in the human body, it is a colorless, syrupy acid formed in fermented milk products like yogurt. Lactic acid fermentation contributes to creating foods rich in healthy probiotic bacteria.
Lactate vs. Lactic Acid: Clarifying the Difference
The terms “lactate” and “lactic acid” are often used interchangeably when discussing their effects on the body. However, experts clarify that “lactic acid” is somewhat outdated and not well understood. Lactate is produced by the body during aerobic exercise, not lactic acid. The distinction lies in their chemical compositions. Lactate is lactic acid minus a proton. Lactic acid donates a proton, transforming into its conjugate base, lactate. For simplicity, this article will primarily use the term “lactic acid” due to its common usage.
The Impact of Lactic Acid on the Body
While many believe lactic acid causes muscle soreness and stiffness, Stephen M. Roth, a kinesiology professor at the University of Maryland, explains that lactate buildup isn’t responsible for post-exercise muscle soreness. Instead, the production of lactate and other metabolites during intense exertion causes the burning sensation felt in active muscles.
Lactic acid buildup contributes to painful sensations during exercise, preventing overexertion and injury. It forces us to slow down, promoting a recovery period where the body clears lactate and other metabolites.
Understanding Lactic Acid Production
Lactic acid is produced in higher amounts during strenuous aerobic exercise because muscles require more oxygen. When exercise intensity exceeds the lungs’ and heart’s capacity to supply oxygen, lactic acid accumulates in the blood.
Lactic acid levels increase in various situations:
- During strenuous exercise, the most common reason in healthy adults.
- In cases of heart failure, liver failure, or pulmonary embolism. Liver damage impairs lactic acid breakdown.
- During severe infections like sepsis.
- As a side effect of metformin, a diabetes medication.
- Due to severe dehydration or overheating.
- In conditions affecting the blood, such as severe anemia or leukemia.
- Due to carbon monoxide poisoning, alcohol poisoning, or poisoning from chemicals like antifreeze.
- Due to nutrient deficiencies, including low thiamine or B vitamins.
When oxygen levels are low, such as during intense exercise, the body breaks down carbohydrates for energy, producing lactic acid. Working muscles generate energy anaerobically from glucose through glycolysis. This process converts glucose into pyruvate, which is temporarily converted into lactate, allowing glucose breakdown and energy production to continue during intense exercise. This anaerobic energy production powers muscles for about one to three minutes, causing lactate levels to rise, leading to muscle fatigue. Eventually, lactate exits cells and is transported to the liver, where it’s oxidized back to pyruvate and converted to glucose via the Cori cycle.
Is Lactic Acid Harmful?
Elevated lactic acid due to exercise is generally a normal, temporary, and harmless reaction. However, significantly high lactic acid levels, known as lactic acidosis, can be life-threatening.
Lactic acidosis occurs when the body produces too much lactate or cannot clear it quickly enough, due to factors like:
- Medications
- Intense exercise
- Respiratory failure
- Heart disease
- Anemia
Symptoms of lactic acidosis extend beyond normal muscle fatigue and may include:
- Trouble breathing/rapid breathing
- Excessive sweating
- Abdominal pain
- Nausea
- Vomiting
- Confusion
- Coma
While potentially fatal, treatment can often manage symptoms and prevent escalation.
Normal Lactic Acid Levels
Doctors can perform a blood test to measure lactic acid levels. In suspected brain infections, the amount of lactic acid in spinal fluid may be measured. A normal venous blood lactic acid range is between 0.5–2.2 milliequivalents per liter (mmol/L), equivalent to 4.5 to 19.8 milligrams per deciliter (mg/dL). A normal arterial blood range is between 0.5–1.6 mmol/L. Arterial measurements are generally more accurate but harder to perform than regular blood tests.
Exploring Lactic Acid in Foods
In addition to being produced in the human body, lactic acid is found in fermented foods. Lactic acid bacteria are present in cultured dairy products like yogurt and kefir, formed via anaerobic respiration by bacterial strains like Lactobacillus. Lactic acid fermentation, essential for producing probiotic foods, is a metabolic process converting glucose and other six-carbon sugars into cellular energy and lactate. According to Science Direct, lactic acid fermentation is the most extensive fermentation process, and the resulting milk can be classified as thermophilic, probiotic, or mesophilic sour milk.
Strategies to Prevent Excessive Lactic Acid Buildup
Although lactic acid isn’t responsible for delayed-onset muscle soreness (DOMS), managing lactic acid buildup can improve workout capacity and recovery.
1. Gradual Increase in Exercise Intensity
Avoid abruptly increasing workout intensity to prevent muscle fatigue. Gradually build stamina and strength to reduce the risk of injury or burnout. Prevent overuse injuries by varying workouts, targeted muscles, and exercise intensity. Ideally, split weekly workouts into aerobic and strength-building sessions. Monitor breathing and heart rate to gauge appropriate intensity. Practice effective breathing techniques and consider using a pulse oximeter during exercise. Slow down and focus on steady breathing to prevent overexertion.
2. Proper Nutrition
Fuel muscles and organs with adequate complex carbs, proteins, and micronutrients from whole foods. Consume a variety of foods, including protein sources, healthy fats, fruits, vegetables, and high-fiber foods. Electrolytes, especially magnesium and potassium, are helpful for managing muscle fatigue. Incorporate natural sources of these minerals, such as nuts, legumes, leafy greens, potatoes, bananas, broccoli, natural orange juice, and dark cocoa. Iron-rich foods like liver, grass-fed beef, lentils, leafy greens, fish, black beans, and nuts can also help fuel the body with oxygen. Consume carbs and protein before and after workouts, such as fruit or oatmeal with yogurt or cottage cheese, or a hard-boiled egg with sprouted grain bread.
3. Rest Days
Rest is essential for the body to clear lactate and other metabolites. Muscle tissue repairs and strengthens during rest, making muscle recovery crucial. Incorporate light exercises like walking, gentle yoga, or swimming on rest days. Avoid high-intensity exercises when feeling sore or tired, and prioritize at least one or more rest days per week.
4. Stretching and Gentle Movement
Stretching before and after workouts supports performance and recovery by increasing blood flow, improving flexibility, and enhancing mental focus. Use dynamic stretches before exercise to boost circulation. After exercise, use ice packs, massage, and warm baths to increase circulation and manage soreness.
5. Prevent Dehydration
Drink enough water to prevent dehydration, fatigue, dizziness, and cramps. Aim for at least eight glasses of water per day, especially if active or in a hot climate.
Risks and Side Effects
While high lactic acid levels from physical exertion are generally safe for healthy individuals, lactic acidosis can increase the risk of serious complications and death in those already ill. Seek immediate medical help if signs of lactic acidosis develop. If you have existing health conditions, consult your doctor before starting intense exercise programs.
Final Thoughts
Lactic acid is an organic acid produced in the body under specific circumstances, especially during strenuous exercise. Primarily produced in muscles and red blood cells, it leads to fatigue and soreness, forming when the body breaks down carbohydrates for energy when oxygen levels are low. Lactic acid is produced by intense exercise, infections, certain diseases, medications, and poisoning. Normal lactic acid levels range from 0.5–2.2 milli-equivalents per liter (mmol/L) in venous blood samples. Managing lactic acid involves rest, hydration, stretching, rest days, and proper nutrition.
