Muscle Fatigue: Causes, Symptoms and Treatment - K Health (2023)

If you've ever exercised vigorously, chances are you've experienced muscle fatigue.

As the workout progresses, the movements that you were able to perform with strength can suddenly become weaker and weaker - until your muscles are not able to "shoot" at all.

There is no single cause for muscle fatigue and there are still things we are learning about the causes and mechanisms behind it.

One thing is for sure: everyone experiences it in training, even the best athletes in the world.

For people looking to maximize their physical performance, certain treatments and supplements can help lessen the effects.

In this article, I'll define muscle fatigue as it applies to everyday life.exercise.

I will describe the main causes and symptoms of muscle fatigue.

I'll discuss the main ways to treat and delay muscle fatigue, including the use of home remedies and supplements.

And I will also discuss when to see a doctor for muscle fatigue.

What is muscle fatigue?

In the medical literature, muscle fatigueIt's definedas a decrease in the strength capacity of a muscle that occurs during exercise.

This definition of muscle fatigue includes two different scenarios that can lead to reduced muscle strength.

First, bodies that are tired from exercise may have reduced signaling ability.,or order,fully contract the muscles.

And second, for whatever "force of contraction" the body is exerting, the actual contractions of a muscle can get weaker and weaker as exercise fatigue sets in.

These two muscle fatigue scenarios can overlap during a single training session.

It all dependsabout the type of exercise and the condition of your body.

Some people can exercise longer before experiencing muscle fatigue, while others tire more quickly.

Even a single person's experience of muscle fatigue can vary from day to day.

What does not fit the standard definition of muscle fatigue is muscle wasting caused by illness.

Some neurological, muscular and cardiovascular diseases, such asand inflammatory and autoimmune diseases, can cause severe and prolonged muscle fatigue and requires immediate medical intervention.

On the other hand, exercise-related muscle fatigueHand, is usually relieved within a few days with just rest and recovery.

Muscle fatigue is also different from muscle injuries, muscle pain andbody pain.

Whereas muscle fatigue is a decrease in strength, muscle soreness is an increase in pain.

causes

There is no single cause of muscle fatigue.

Different exercise scenarios can trigger different pathways to muscle weakness.

Muscle fatigue may progress in one direction during this timeaerobic exercisewhich puts a lot of pressure on the respiratory muscles, such as the diaphragm, and in other ways during strength training, which puts special pressure on the skeletal muscles.

Physicians are learning more every day about the precise cellular-level mechanisms behind muscle fatigue.

It is already clear that there may in fact be several causesIncluding:

• insufficient oxygen: In certain sports, low levels of oxygen in the environment or in the body can accelerate fatigue. Oxygen helps cells break down a substance called glucose, which gives muscles the energy they need to "fire" and contract.
  
• not enough energy: When levels of glucose and other energy sources in muscle cells are very low, muscle fatigue can accelerate.
  
• impaired calcium release: The release of calcium molecules appears to play an important role in signaling skeletal muscle fibers to "fire" during exercise. As exercise progresses, the release of these calcium molecules appears to be impeded.
  
• Accumulation of metabolites and inorganic phosphate: Metabolites are substances that remain in cells when the body breaks down glucose and other sources of energy. During exercise, the accumulation of these metabolites appears to play a role in increasing muscle fatigue. For example, when extra energy is needed, the body usually breaks down a substance called creatine phosphate, leaving a buildup of inorganic phosphate as a metabolite. This accumulation of phosphateappears to be one of the main causes of muscle fatigue, in part due to the way it interferes with the calcium signaling system.
  
• Not getting enough vitamins, minerals or electrolytes: Significant deficiencies in substances such as folic acid, iron and vitamin B12 can make it difficult for red blood cells to deliver oxygen to muscles. Charged electrolytes like calcium, magnesium, potassium, and sodium help muscles contract.
  
• insufficient water: Dehydration can delay andlimit blood flow to the musclesWhile training.

Previously, it was believed that the accumulation of lactic acid in muscles during exercise was a major cause of muscle fatigue.

It is true that lactic acid builds up as exercise progresses and that lactic acid in very high degrees can cause lactic acidosis, which can cause burning sensations and muscle cramps.

There is little evidence that lactic acid itself causes muscle weakness, as well as inorganic phosphate accumulation appears to cause fatigue directly. In fact,Lactic acid can actually help delay muscle fatigue!

symptoms

Muscle fatigue symptoms tend to be progressive.

You are unlikely to go from full muscle strength to complete muscle exhaustion in a short time.

Instead, you will experience a gradual reduction in the strength of your muscle contractions.

How this weakness looks and feels depends on the type of muscles you train the most.

If you run fast and use your breathing muscles heavily, you are likely to experience muscle weakness as you become increasingly out of breath.

If you heavily train your arms or legs with weights, you may find it increasingly difficult to complete your lifting sets as your muscle strength declines.

When doing advanced yoga, you may find that your form slips as your stabilizer muscles tire.

treatment

Under normal circumstances, the best way to "treat" muscle fatigue is through rest and recovery.

This means you don't have to re-strengthen tired muscles the days after a hard workout.

It also means building warmups and cooldowns into all your workouts and taking time to rest between sets.

home remedies

There are also many steps you can take between heavy workouts to treat and prevent muscle fatigue.

Some of the main remedies are sleep and abalanced nutrition.

Carbohydrates are particularly important so that your muscles are sufficiently supplied with glycogen and other energy sources during training.

Hydration with water or sports drinks can also help prevent dehydration and maintain electrolyte levels.

You can also work on building your breathing endurance and lung capacity through aerobic exercises at home.

This ensures you get enough oxygen the next time you exercise your muscles.

when to the doctor

Although muscle fatigue caused by exercise should resolve with rest, more severe forms of muscle fatigue may not.

Rather, they may be associated with a serious illness.

Contact your doctor immediately if previous light physical activity has been making your muscles tired for a long time or if you experience additional muscle heaviness:

• Debilitating body aches
• Loss of mobility or difficulty walking
• Difficulty swallowing, eating or drinking
• breathing difficulties ordizziness
• Heavy water retention
• Persistent pain that doesn't get better with home treatments
• body painrelated to a tick bite or an unexplained rash
• Fever(a temperature of 100°F/37.8°C or higher)
• shortness of breathe
• chest pain
• ONEtorticollis
• light sensitivityor other visual changes
• Extremelyfatiguedoes not improve with sleep
• fainting, seizures or loss of consciousness
• nausea and vomit
• Unexplained body aches that last longer than two weeks
• weakness in arms or legs

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K Health articles are all written and reviewed by MDs, PhDs, NPs or PharmDs and are for informational purposes only. This information does not constitute professional medical advice and should not be relied upon. Always talk with your doctor about the risks and benefits of any treatment.