Finding a good pre-workout formula can be a challenge. Knowing what ingredients you want is one thing; dosages is another; and finding the correct form of each ingredient? That’s a whole other ballgame.

But if one thing is for certain, you want to make sure you’re covering your bases. You want something that:

  • Increases energy
  • Reduces fatigue
  • Supports strength and stamina
  • Increases endurance
  • Accelerates recovery

Once you’ve ticked those, it’s time to determine what’s going to do the job. And in pre-workouts, there are a few ingredients that tend to steal the spotlight—caffeine, creatine, beta-alanine, and BCAAs, to name a few—but one we rarely hear about is another amino acid… L-theanine.

Whether you’ve seen it before or it’s totally new, we’re breaking down everything you need to know about L-theanine—what it is, what it does, and the best form you should be looking for in your pre-workout.

What Is L-Theanine?

Ever drank a cup of tea before? If so, you’ve consumed L-theanine. It’s an amino acid isolated from both green and black tea leaves that has been shown to be beneficial for mental health and mood due to its ability to block the binding of L-glutamic acid to glutamate receptors in the brain, which may influence psychological and physiological states when exposed to stressors 1.

L-theanine also happens to be one of the most powerful nootropic compounds and should be a staple in everyone’s supplement stack for the potent cognitive benefits it provides, whether for workouts or otherwise.

But what’s really interesting about L-theanine is that it may inhibit some of the nasty high-stim effects that caffeine can cause. Some research has shown that L-theanine is able to inhibit the stimulation produced by caffeine, as well as reduce heart rate, lower subjective levels of perceived ‘stress’, elevate visual attentional performance, and improve reaction time response 2, 3.

Part of the reason it may be able to do this is by increasing alpha brain wave activity without inducing drowsiness 4; alpha brain waves are present when you’re in a relaxed yet inattentive state.

The thing with L-theanine is that even though it’s present in decently high concentrations in tea, drinking only tea is likely not going to provide enough to fuel your mind, which is where supplementation comes in handy.

L-Theanine And Your Brain

Where L-theanine is concerned, there are a few reasons why we love it in a pre-workout.

Whether you’re downing a cup of coffee before training or knocking back a pre-workout that contains caffeine, the stimulant effects can be a bit overwhelming.

Some people can handle the high-stim side effects, while others experience a rapid onset of jitters, nervousness, anxiety, and lack of focus—the exact opposite of what you want during your workout.

But when you add L-theanine to a pre-workout, it absorbs rapidly and acts antagonistically against paralysis induced by caffeine 5. As such, it may be able to counteract some of those nasty side effects to promote a calm, clean, relaxed stimulation like you’ve never experienced before.

L-theanine also offers some great neuroprotective properties that can help prevent damage caused by oxidative stress and free radical formation, which is inevitable during intense physical activity.

And what’s more, it helps to calm the mind and promote cleaner stimulation for a smooth, effective workout without the drowsiness of most sedative compounds.

And when you combine L-theanine with other bioactive compounds like caffeine, you’re getting bigger and better benefits with minimal side effects; it’s the ultimate balance between stimulation and relaxation.

Want more? Regular consumption of L-theanine has also been shown to 6, 7:

  • Up-regulate alpha brain wave activity for improved cognitive abilities
  • Reduce anxiety by increasing serotonin and GABA
  • Reduce psychological and physiological stress responses

Difference Between L-Theanine And Suntheanine®

When it comes to finding the form of L-theanine that’s going to produce the best results both in and out of the gym, there’s no competition.

L-Theanine is the form of the amino acid derived from tea, while Suntheanine® is the superior form produced via a patented process mimicking the natural process like that in green tea leaves, resulting in a 100% pure L-isomer-theanine. Despite being the same amino acid with different derivatives, they are both intended to elicit the same benefits within the body.

Like L-theanine, Suntheanine® is absorbed in the small intestine via a sodium-coupled active transport process and is able to cross the blood-brain barrier where it influences brain function.

In the brain, Suntheanine® directly stimulates an increase in alpha brain wave activity—a state often achieved through meditation and one that is deeply relaxed and mentally alert.

It plays a role in the formation of the inhibitory neurotransmitter GABA (also the main anti-anxiety neurotransmitter) and increases the release of dopamine by modulating glycine and AMPA receptors. As such, it promotes relaxation and inhibits excitatory chemicals in the brain for an alert, calm, and relaxed effect without any drowsiness.

What’s Better?

Suntheanine® L-theanine is the most powerful and purest form of L-theanine available to power your brain like no other supplement on the market. Because pre-workout supplements are notorious for loading up on caffeine that can result in unpleasant side effects like jitters and anxiety, Suntheanine® helps you achieve power, control, intensity, and accuracy by smoothing out the jitters and stress associated with high-stim pre-workouts.

Both traditional L-theanine supplements and Suntheanine® support brain health and enhance cognition, however, when you’re looking for clean stimulation, drive, and intensity, you want maximum concentration.

Suntheanine® provides that. The patented proprietary technology of Suntheanine® gives you 10x more L-theanine than green tea for a much more concentrated effect.

And in Pre Lab Pro®, we only want to give you the best and most powerful dosages.

The Suntheanine® form of L-theanine has been shown in human research to reduce the tightening, circulation-limiting effect of caffeine, and in Pre Lab Pro®, this benefit allows caffeine’s ergogenic benefits to peak without interfering with the RedNite® + Setria® Performance Blend circulation boost.

It’s the ultimate ingredient for the ultimate workout-enhancer.

The Suntheanine® Difference

  • Premium 100% pure, nature-identical L-isomer form
  • Patented fermentation process mirrors the profile of green tea
  • Protected by over 40 additional U.S. and international patents
  • Shown in human clinical research to boost calming, focus-enhancing alpha brainwaves
  • Concentrated 160 mg Suntheanine® supplies L-Theanine equivalent to 16 cups of green tea
  • Clean and reliable, backed by over 60 clinical studies

Final Thoughts

L-theanine and Suntheanine® are both awesome when it comes to supporting cognitive performance, but when you’re looking for calmness and focus through even the toughest workouts, there’s only one way to go—Suntheanine®.

It’s been shown in dozens of clinical studies to balance the stimulatory effects of caffeine for superior focus and intensity through every workout.

It will give you consistent and immediate results time and time again for the best performance in and out of the gym.


  1. K Kimura, M Ozeki, LR Juneja, H L-Theanine reduces psychological and physiological stress responses.Biol Psychol. 2007;74(1):39-45.
  2. CF Haskell, DO Kennedy, AL Milne, KA Wesnes, AB Scholey. The effects of l-theanine, caffeine and their combination on cognition and mood. Psychol. 2008;77(2):113-122.
  3. A Higashiyama, HH Htay, M Ozeki, LR Juneja, MP Kapoor. Effects of l-theanine on attention and reaction time response. Funct. Foods. 2011;3(3):171-178.
  4. AC Nobre, A Rao, GN Owen. L-theanine, a natural constituent in tea, and its effect on mental stateAsia Pac J Clin Nutr. 2008;17 Suppl 1:167-168.
  5. LR Juneja, DC Chu, T Okubo, Y Nagato, H Yokogoshi. L-theanine—a unique amino acid of green tea and its relaxation effect in humans. Trends Food Sci Technol. 1999;10(6-7):199-204.
  6. PJ Nathan, K Lu, M Gray, C Oliver. The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent.J Herb Pharmacother. 2006;6(2):21-30.
  7. K Kimura, M Ozeki, LR Juneja, H L-Theanine reduces psychological and physiological stress responses.Biol Psychol. 2007;74(1):39-45.