Bodybuilding is a tough game. It takes copious amounts of dedication, consistency, and willpower to get through heavy workouts, proper recovery, and bulking and cutting cycles to achieve the best physique possible.

And for bodybuilders looking to get a competitive advantage over their competition, there is no shortage of supplements geared towards maximizing muscle and strength gains while curbing fat gain. Be it creatine, pre-workouts, amino acids, glutamine, carbs, or the like, supplementation is a key part of bodybuilders' program.

However, one supplement we hear little about that seems to be in all the best formulas is L-theanine, an amino acid known for its sedative effects. While we may not be looking to put you to sleep amid a high-volume training session, there are some good reasons why this amino acid is turning heads.

It may not be the talk of the bodybuilding town yet, but it's making its face known. L-theanine offers some major benefits for training, and we want you to get in on them.

Let's dive in.

What Is L-Theanine And How Does It Work?

Tea has been consumed for centuries worldwide and is said to possess plenty of health benefits, including loads of antioxidants. But aside from being a rich source of antioxidants, tea also naturally contains the amino acid L-theanine, which has been shown to modulate several aspects of cognitive function due to its ability to alter patterns of brain activity 1.

While it's not the only health-promoting compound found in tea, L-theanine is the major amino acid and is thought to be the compound responsible for giving tea its unique flavor. In a 200ml serving of tea, there is anywhere from 25 to 60mg of theanine, with the predominant form being L-theanine over D-theanine 1.

Studies show that L-theanine can quickly cross the blood-brain barrier to exert its effects within approximately 30 minutes of consumption, making it a great compound for a quick cognitive boost.

One of the main mechanisms behind L-theanine's powerful cognitive effects is via the glutamate pathway. L-theanine is structurally similar to the neurotransmitter glutamate, which means it can weakly bind to glutamate receptors and acts antagonistically to elicit inhibitory activity on glutamate transporters 2.

As such, it blocks the reuptake of both glutamine and glutamate to calm down an overstimulated or overexcited brain. It's also been shown to increase dopamine and serotonin production in the brain, which plays a significant role in relaxation, reward, and mood through enhancing alpha brain wave activity.

A 2008 study confirmed that L-theanine has a significant role in modulating the resting state of brain activity 1. It appears to enhance the power of alpha brain waves, which supports achieving a relaxed but alert mental state via a direct influence on the central nervous system.

Additionally, alpha brainwave activity is a key component in focused attentional processes; research shows that directed deployment of alpha brain activity appears to be an essential part of the ability to suppress distracting visual information during highly demanding tasks, and L-theanine can enhance this alpha attention effect 3.

As a result, L-theanine can:

  • Increase focus and attention
  • Reduce levels of stress and anxiety
  • Enhance sleep quality
  • Improve mood
  • Increase motivation
  • Enhance memory

Benefits Of L-Theanine For Bodybuilders

1. Mitigates The Effects Of Stimulants

Whether you're looking to pump up your energy for a week of heavy training or dialing down your diet for an intense cut, there's no denying that caffeine—on its own or in a pre-workout—can be beneficial.

It increases alertness and focus, dilates blood vessels for better blood flow, decreases the perception of fatigue, and may boost endurance, strength, and power performance. While all of that is great, we tend to shy away from the nasty side effects of caffeine.

That's things like dehydration, sleep disruptions, reliance, and the energy crash that usually accompanies high doses of caffeine.

The reality is that caffeine puts you in the zone. It helps you focus and drives up the energy to get you through the intense and gruesome training sessions you endure daily. It's precisely why coffee is one of the most widely consumed beverages worldwide.

But where L-theanine shines is working synergistically with caffeine to give you the same benefits without the side effects. Caffeine works by acting as an adenosine-receptor antagonist; adenosine is a molecule in the brain that is responsible for inducing drowsiness when in high concentrations 4.

However, as caffeine is a structural analog to adenosine, it binds to adenosine receptors in the brain. It prevents the actions of adenosine, thereby having a powerful influence on brain functions like sleep, cognition, learning, and memory, along with modifying brain dysfunctions and diseases.

By itself, L-theanine is a powerful nootropic that promotes calm, focus, stable mood, and more, which in and of itself is beneficial for bodybuilders, but when combined with caffeine, there's a pronounced synergistic effect.

You're getting heightened focus, awareness, and energy, along with reduced stress and improved mental endurance for better performance in and out of the gym.

A 2008 study compared the effects of l-theanine, caffeine, and their combination on cognition and mood 5. Results showed that caffeine ingestion led to faster digit vigilance reaction time, improved Rapid Visual Information Processing (RVIP) accuracy, and attenuated increases in subjective ratings' mental fatigue'.

Along with improving RVIP accuracy and 'mental fatigue' ratings, the combination of caffeine + L-theanine also reduced headache' and 'tired' ratings and increased 'alert' ratings.

The result of L-theanine + caffeine is an increase in energy and focus without the jitters and crashes associated with overconsumption of caffeine. It's simple, and it's gold.

2. Improves Sleep

Sleep is perhaps one of the most undervalued forms of recovery for athletes. Most often, training programs and diet take the front seat where performance and results are concerned, but lifestyle factors like sleep and stress management are non-negotiable if you want to see any sort of performance enhancement.

And while you may be sleeping the 7-9 hours that's recommended, if you're not getting quality sleep, then the duration doesn't matter.

Studies consistently show that sleep deprivation not only leads to weight gain, fat accumulation, and metabolic dysfunction, but it also leads to major decrements in physical performance and muscle growth/repair.

The reason why is because the majority of growth hormone secretion happens during sleep, so if you're not getting adequate amounts, or not getting adequate slow-wave sleep, your growth hormone levels are going to suffer along with your ability to build and maintain muscle mass; approximately 70% of growth hormone pulses during sleep coincide with stage 3 non-REM (slow-wave sleep) 6.

Lucky for us, L-theanine is sleep-supportive. It's been shown to exhibit sedative effects, along with modulating levels of neurotransmitters and reducing levels of stress, both of which are important for inducing sleep 7.

It also helps increase levels of serotonin, dopamine, and GABA in the brain, and when combined with GABA supplementation, it can decrease sleep latency and improve non-REM sleep.

Simply put, less sleep = less muscle growth. It's not only that sleep helps muscles grow, but lack of sleep can decrease muscle mass.

A 2011 study looked at the effects of sleep and muscle recovery and found that people who slept only 5.5 hours had 60% less muscle mass at the end of the study compared to those who slept 8.5 hours and had 40% more muscle mass 8.

If that's not enough to convince you to sleep more, we're not sure what is.

3. Boosts Endogenous Antioxidants + Immune Function

One of the lesser-known benefits of L-theanine is its ability to enhance levels of glutathione, one of the most important antioxidants in the human body that's also heavily involved in immune responses.

Because high-intensity bodybuilding workouts do major damage to muscle fibers and trigger the inflammatory cascade, the damage can also promote biochemical changes within the affected area, leading to the production of inflammatory cytokines and reactive oxygen species (ROS).

These further contribute to muscle degradation and signs and symptoms of injury (e.g. loss of muscle force, muscle soreness, etc.) 9. However, research shows that L-theanine may help to augment levels of glutathione, which can help to bolster immune function and accelerate recovery from strenuous exercise 10.

4. Increases Your Pump

Still not on side with L-theanine? You're about it be. Because of its ability to boost NO production, it may do wonders for your performance and muscle growth.

Nitric oxide is a bodybuilder's best friend when it comes to chasing the pump because endothelial nitric oxide is the key regulator of vascular functions in endothelium 11.

Studies show that L-theanine promotes nitric oxide (NO) production in endothelial cells, which not only mediates vascular health but for bodybuilders helps to increase blood flow to active muscles for better nutrient delivery, thus helping muscles grow larger when subjected to stress.

Final Thoughts

There's no doubt that L-theanine is an undervalued nutrient in the bodybuilding world, but we've given you four major reasons why it should be upfront.

Whether you're looking to avoid the effects of high-dose caffeine, in need of better sleep to support a stronger recovery or to boost your pump mid-workout, L-theanine shows a lot of promise for improving several aspects of bodybuilders' performance.


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