Is CNS Fatigue the Reason You’re Not Hitting Your Goals? (Here’s What to Know)

Ever hit a wall in your training, feeling exhausted despite well-rested muscles? Central Nervous System (CNS) fatigue might be the answer. Hardcore trainers and weekend exercisers alike may find this overlooked problem holding them back.

CNS fatigue happens when your brain and spinal cord struggle to communicate efficiently with your muscles. It’s not just about physical tiredness – it’s a complex interplay of neurotransmitters, brain function, and muscle response.

This article explores the science behind CNS fatigue, its symptoms, and practical strategies to overcome it. Let’s get started!

What is CNS Fatigue? 

CNS fatigue arises when frequent, intense workouts lead to muscle exhaustion. As muscles fatigue, motor neurons, which send signals to the brain, prompt the brain to reduce its responsiveness. This results in fewer signals being sent back to the muscles, leading to a drop in performance. This breakdown in communication between the brain and muscles is what characterizes CNS fatigue, making it challenging to maintain the same level of exercise intensity.

The brain and body are in constant communication. Muscles require approval from the brain, specifically from the motor cortex located at the front of the brain. This region is responsible for sending out commands for all movements. Without these signals, muscles cannot function independently.

In strength training, the goal is often to avoid CNS fatigue, as it can prevent the activation of the strongest muscle fibres—those crucial for lifting heavy weights or running at top speed. Recognizing the symptoms of CNS fatigue, such as extreme tiredness and a noticeable decrease in performance, allows individuals to manage their workouts more effectively, preventing overexertion.

To recover from CNS fatigue, it’s essential to have a well-thought-out plan that includes sufficient rest, proper nutrition, and strategically planned workouts. 

Mechanism of Central Nervous System Fatigue

In case muscles are at risk of damage and the motor cortex is not pausing. The controlling mechanism comes into action to control the system.

Given below are three famous mechanisms of CNS fatigue:

• Activation of inhibitory feedback loop

Afferent nerve fibres (ascending nerve endings) signal the brain to cease activating motor fibres that activate muscle contractions. Afferent nerve fibres originate from mechanoreceptors (receptors that sense mechanical loading) and possess accessible nerve endings that feel pain when muscles get damaged or hyper-extended. The activation of afferent nerve fibres is linked to the activation of pressure and pain-sensitive receptors. Inflammation further lowers the threshold of pain sensitisation.

Increased production of free-circulating tryptophan

According to research, when the energy depot goes down (reserved ATP), stressed muscles start rapid uptake of Branched Chain Amino Acids (BCAA). This voracious consumption of BCAA increases the concentration of free circulating tryptophan in the blood. Tryptophan, a serotonin precursor, increases the production of Serotonin inside the CNS. Serotonin is linked to fatigue, lethargy, depression and declining motivation. Hence, with the entrance of Serotonin, neurons stop, signals are paused, and muscles stop contracting. Gymgoers feel that CNS is fatigued.

Neurotransmitters involved in CNS Fatigue

Neurotransmitters are messengers that convey the message of one neuron to another and develop a transmission network for bringing communication and coordination into play inside the CNS. They decide when signals must go down and when not. For example, Serotonin is the inhibitory neurotransmitter that breaks the activation loop, as discussed above, whereas dopamine is an excitatory one that brings forth the activation, motivation, and movements.

In 1997, JM Davis wrote: “Good evidence suggests that increase or decrease in brain serotonin activity during prolonged exercise hasten and delay the fatigue.” Hence, it’s admitted that the play of messengers in the brain rules over the dreams of the muscle gainers. 

The following neurotransmitters play a major role in CNS fatigue:

Serotonin (5-HT)

Increased levels of serotonin in the brain during prolonged exercise or mental exertion are associated with feelings of tiredness and lethargy. This is often referred to as the “central fatigue hypothesis,” where higher serotonin levels contribute to sleepiness and fatigue. Serotonin levels can become elevated due to sustained physical or mental stress, which triggers its production as the body attempts to regulate mood and energy.

Dopamine

Dopamine is involved in motivation, reward, and motor control. During CNS fatigue, dopamine levels can decrease, leading to reduced motivation and an increase in perceived effort. Prolonged stress or overexertion can deplete dopamine levels as the body uses more of it to maintain energy and focus, eventually leading to fatigue.

Noradrenaline (Norepinephrine)

Noradrenaline plays a role in maintaining alertness and attention. CNS fatigue can occur when noradrenaline levels drop, contributing to reduced cognitive performance and increased fatigue. The production of noradrenaline can be disrupted by sustained stress, which may deplete the body’s resources needed to maintain its levels.

GABA (Gamma-Aminobutyric Acid)

GABA is an inhibitory neurotransmitter that helps regulate neuronal excitability. Increased GABA activity can contribute to CNS fatigue by reducing neural activity and promoting relaxation or sleepiness. The levels of GABA may rise in response to prolonged stress as the body attempts to counteract excessive neural activity and prevent overexcitation.

Glutamate

Glutamate is the primary excitatory neurotransmitter in the CNS. While essential for cognitive function and motor activity, excessive glutamate release can lead to excitotoxicity and contribute to CNS fatigue. High levels of stress or overactivity can cause an overproduction of glutamate, overwhelming the brain and leading to fatigue.

Acetylcholine

Acetylcholine is involved in attention, learning, and memory. A decline in acetylcholine activity during prolonged activity can contribute to CNS fatigue by impairing cognitive and motor functions. Stress and sustained effort can deplete acetylcholine as the brain consumes it more rapidly than it can be replenished.

 

Signs and Symptoms of Central Nervous Fatigue

Below are some of the common signs and symptoms of CNS fatigue:

• Anxiety
• Irritability
• Headaches
• Weakness
• Poor sleep
• Poor memory
• Mental fog
• Mood changes
• Lack of energy
• Depression
• Reduced stamina
• Joint aches and pains
• Disturbed appetite
• Muscle aches and pains
• Persistent fatigue
• Reduced mental clarity
• Difficulty concentrating
• Fever and flu-like symptoms
• Impaired decision-making
• Inability to perform easy tasks
• Loss of interest in activities

Central Nervous System Fatigue Recovery

Central Nervous System recovery time can take less than 20 minutes to several days and weeks. It depends on how adequately trainees maintain themselves during fatiguing training regimens (two to twelve/ fourteen weeks training sessions). Suppose optimum sleep, appropriate nutrition, and ideal rest days are held during training fellowships. In that case, the risks of getting CNS fatigue are reduced, and one can enjoy prolonged and strenuous sessions with merriment and jubilation.

However, if one performs high-intensity workouts over days with no breakouts, chronic CNS fatigue quickly becomes its way, and it takes days to get rid of it completely. Some tips below are shared that one may consider as per choice.

• Sleep Until Sufficient Strength is Regained

Quality sleep is paramount for CNS recovery. During deep sleep, the brain and central nervous system undergo crucial repair processes. Aim for 7-9 hours of uninterrupted sleep nightly, and consider power naps (20-30 minutes) between training sessions if possible. Create a sleep-conducive environment by keeping your bedroom dark, quiet, and cool. Limit exposure to blue light from electronic devices before bedtime, as this can disrupt your sleep-wake cycle. If you’re experiencing severe CNS fatigue, don’t hesitate to extend your sleep duration until you feel your strength and mental acuity returning.

• Add Essential Nutrients in Your Diet

According to Meeusen and Decroix, the necessary intake of proteins and fats is needed to build muscles. Focus on consuming foods rich in omega-3 fatty acids, such as fatty fish, walnuts, and flaxseeds, which support brain health and reduce inflammation. Incorporate antioxidant-rich foods like berries, dark leafy greens, and colourful vegetables to combat oxidative stress. Ensure adequate protein intake to support muscle repair and neurotransmitter production. Complex carbohydrates provide sustained energy for the brain and central nervous system. Consider supplements like magnesium, which aids in nerve function and muscle relaxation, and B-complex vitamins, which are crucial for energy metabolism and nervous system health, should be considered.

• Remove all Triggers of External Stress

Despite retaining adequate nutrition, and proper rest, many folks struggle with attaining recovery. If present in the family or surroundings, disturbing elements keep the person stressed. Worries and grieves attract cortisol, further aggravate CNS fatigue, and let the body feel that it’s under attack. Such scenarios, if existing, instead of bringing recovery, begets lethargy and deprive the person of both physical and mental wellness.

• Make Changes To Your Lifestyle

Start by adding variety to your life. Pick up a new hobby or interest outside of your usual sports and exercise. Even a brisk walk can work wonders. It gets your blood flowing and clears your head, often helping you feel refreshed.

Pay attention to what you eat and drink. Your body has specific needs, and meeting them can make a huge difference. Some foods might give you energy, while certain drinks could be draining you. Listen to your body and adjust accordingly.

Many people lack important nutrients like magnesium and iodine. These shortages can mess with how your body works, affecting everything from your cells to your hormones. Your thyroid, a tiny but crucial gland, especially needs these nutrients. If you’re unsure, a blood test can reveal any deficiencies.

Your environment matters, too. Surround yourself with positive, healthy people and avoid toxic relationships. The company you keep and the places you spend time in can either boost your energy or drain it.

• Stretch and foam roll exercise

Try stretching and foam rolling. These simple exercises can make a big difference in how your body recovers.

Aim for about 30 minutes a day of stretching and foam rolling. This helps your body in several ways:

1. Loosens tight muscles
2. Improves blood flow
3. Helps remove waste from your muscles
4. Speeds up muscle and nerve recovery

Stretching is like giving your muscles a gentle massage. It helps them relax and grow stronger. Foam rolling goes a step further. It’s like a deep tissue massage you can do yourself. The foam roller helps break up knots in your muscles and fascia (the tissue around your muscles).

Here’s a simple way to start:

1. Stretch major muscle groups for 15 minutes
2. Use a foam roller on your legs, back, and arms for 15 minutes
3. Focus on areas that feel tight or sore
4. Breathe deeply and relax as you do these exercises

Remember, don’t rush. Take your time and listen to your body. If something hurts, ease off a bit.

Want to learn more? Check out this step-by-step guide on foam rolling and stretching:  link.

Looking to Recover Faster? Consider These Therapies

When dealing with CNS fatigue, recovery can often feel slow and challenging. However, certain therapies speed up the process and improve recovery. Two such therapies are Pulsed Electro-Magnetic Field (PEMF) Therapy and Far Infrared Therapy.

• Pulsed Electro-Magnetic Field (PEMF) Therapy

Pulsed Electro-Magnetic Field (PEMF) therapy uses electromagnetic fields to stimulate and train cells, helping to correct cellular functions and improve overall health. This therapy is effective in addressing CNS fatigue as it can reach deep into the body’s tissues, improving workability and mental health. Dr. Christopher Williams from Interventional Orthopedics of Atlanta recommends PEMF therapy to his patients, as it has been shown to improve their well-being.

• Far Infrared Therapy

Far Infrared Therapy uses infrared rays to relieve pain and reduce inflammation. Infrared light reaches deep layers of the skin, providing pain relief and promoting faster healing. This therapy is natural, safe, and non-invasive, making it suitable for those experiencing CNS fatigue. By increasing cell function, infrared therapy helps the development of new muscle cells and tissues, speeding up the recovery process after muscle damage.

What if you could get the benefits of both PEMF therapy and Far Infrared therapy in one convenient mat? The Qi Mat combines these powerful recovery modes, along with Negative Ion, Red Light Therapy, and Heat, to help accelerate CNS recovery, reduce CNS fatigue, and promote better sleep. This mat is designed to support your body’s natural healing processes, helping you recover faster and feel refreshed so you can get back to your training regimen with renewed energy and focus. By addressing the specific challenges of CNS fatigue, the Qi Mat ensures that both your body and mind are ready to perform at their best.

Myths About CNS Fatigue

Several myths regarding CNS fatigue are commonly believed to be true despite lacking documented evidence. One widespread belief is that the heavier the training intensity, the greater the CNS fatigue. However, a 2007 study by Tejin Yoon concluded that “the low-force task-induced more significant central fatigue than the high-force contraction for both men and women.”

Another prevalent notion is that it takes 48-72 hours for the CNS to fully recover from fatigue. Yet, in 2012, M. Behrens conducted a study on trained athletes and found that “it took just 20 minutes for the CNS to recover completely, and in competitive athletes, this recovery was not as obvious.”

Therefore, CNS fatigue is relatively short-lived, although certain aspects of CNS functioning remain compromised until the muscles fully recover and inhibitory feedback ceases.

Conclusion 

CNS fatigue affects athletes and fitness enthusiasts in ways that often surprise them. It’s not just about tired muscles; it’s about your brain and spinal cord changing how they work with your body. By spotting CNS fatigue early and using targeted recovery methods, you can train more effectively and avoid burning out. Pay attention to how your body responds to workouts and rest. 

People Also Ask:

What Does CNS Fatigue Feel Like? 

CNS fatigue feels like extreme tiredness, decreased motivation, and difficulty concentrating. You may experience slower reaction times and reduced physical performance.

How Do You Recover from CNS Fatigue? 

Recover from CNS fatigue with quality sleep, proper nutrition, and reduced training intensity. Incorporate rest days and stress-reduction techniques like meditation or light exercise.

How to Test for CNS Fatigue? 

Test for CNS fatigue by monitoring grip strength, vertical jump performance, or using a reaction time app. Consistent decreases in these metrics may indicate CNS fatigue.

What Are the Symptoms of Systemic Fatigue? 

Systemic fatigue symptoms include persistent tiredness, muscle weakness, headaches, and difficulty concentrating. It often affects multiple body systems and daily functioning.

What Is the Recovery Time for CNS Fatigue? 

CNS fatigue recovery time varies from 20 minutes to several days. Factors like sleep quality, nutrition, and overall stress levels influence recovery duration.

What Exercises Help with CNS Fatigue? 

Low-intensity exercises like walking, swimming, or yoga help with CNS fatigue. These activities promote blood flow and relaxation without overtaxing the nervous system.

Can Lifting Cause CNS Fatigue? 

Yes, lifting can cause CNS fatigue, especially with high-intensity or prolonged sessions. Heavy compound exercises are more likely to induce CNS fatigue than isolation exercises.

What Causes CNS Fatigue? 

CNS fatigue is caused by prolonged or intense physical exertion, lack of sleep, poor nutrition, and chronic stress. It results from overworking the central nervous system.

What Is CNS Fatigue? 

CNS fatigue is a decrease in central nervous system performance due to overexertion. It affects brain-muscle communication, reducing physical and mental capabilities.