You’ve probably landed on this article because you’re looking for the top pre-workout supplements to get you into beast mode and maximize your results.

When it comes to pre-workouts, there’s no end of options available for you. From pure supplements like creatine, caffeine, BCAAs, and beta-alanine, to all the pre-workout formulas you can imagine, how do you choose? And how do you know what’s actually effective?

If you’re ready to take your pre-workout training stack to the next level and you’re eyeing down L-theanine to add in, we’re giving you everything you need to know about how this guy can affect your performance and whether it deserves a spot.

What Is L-Theanine?

Magnesium is one of the most common supplements for lifters or casual gym goers who experience a lot of stress and sleep issues, but we don’t frequently encounter a supplement that promotes relaxation and helps you attain more focused and productive training sessions. One like that? It’s essential.

That’s where L-theanine comes into the picture.

Favored by the legendary Charles Poliquin, L-theanine is a naturally occurring non-essential amino acid found in green tea leaves that’s really effective for reducing both physical and mental stress, enhancing cognitive function, and boosting sleep quality because of its ability to readily cross the blood-brain barrier 1.

What Does L-Theanine Do?

The reason L-theanine works is that it boosts levels of GABA and serotonin. GABA is the main inhibitory neurotransmitter in the brain that’s one of the most powerful anti-anxiety and anti-stress compounds, and serotonin is your happy hormone.

But interestingly, L-theanine has been shown to counteract some of the adverse effects of caffeine, especially where sleep is concerned.

Other studies find that L-theanine can boost alpha brain wave activity to promote better focus and more alertness without the drowsiness component 2.

So, for anyone that can’t kick the caffeine habit because of your pre-workout or daily coffee, theanine may be up your alley.

Should L-Theanine Be Taken Pre-Workout?

Caffeine is no doubt one of the most widely consumed supplements pre-workout. It activates your nervous system and drives focus and energy to power through your workout like an absolute animal.

But alongside caffeine in many pre-workouts, you’ll also find L-theanine… why?

When used in a pre-workout with caffeine, L-theanine can help to attenuate or counteract the negative effects of caffeine, especially the jittery feelings and energy crash after it wears off.

Here’s why taking L-theanine pre-workout may offer some pretty powerful advantages.

Boosts Cognitive Performance

We’ve long thought that training sessions were a physical thing, but they’re just as mental as they are physical.

And if you’re looking to get that edge on your buddies where the mental aspect is concerned, combining L-theanine with a caffeinated pre-workout supplement is definitely the way to go.

Studies routinely suggest that when combined with caffeine, theanine is beneficial for improving outcomes on cognitively demanding tasks 3. It helps to enhance the energizing and concentration-boosting effects, giving you cleaner and smarter stimulation with none of the typical caffeine-induced side effects.

In one study, researchers tested the effects of 25 mg of caffeine and 150 mg of L-theanine separately and together to see the effects on various cognitive markers 4. Would they work as stand-alone supplements, or did they produce a ‘smart’ effect when combined?

What they found confirmed the benefits of taking a caffeine L-theanine blend:

  • Less mental fatigue
  • Better memory
  • Improved reaction time
  • Fewer headaches and tiredness

It’s like jacking up the effects of caffeine but getting fine-tuned performance stimulation and none of the after-effects.

Mitigates Blood Pressure Changes

That rush you get after taking pre-workout that sets the stage for your entire workout and makes you feel like you can conquer the world? That’s caffeine.

As a central nervous system stimulant, one of the jobs of caffeine is to get your blood pumping, which increases your blood pressure, heart rate, and energy levels.

But an increase in blood pressure signifies constriction of the vessels, which is the total opposite of what we want during a workout; we want maximum dilation to push nutrients and blood to working muscles.

Combining L-theanine and caffeine helps reduce vasoconstriction and improve circulation within the brain, helping maintain healthy blood pressure.

One study found that combining 75mg of caffeine with 50mg of L-theanine completely eliminated the vasoconstriction effects of caffeine without negatively affecting its stimulatory effects 5. Better blood flow means a better workout.

Improves Overall Performance

As an athlete, you’re always looking for that edge. A new supplement to boost your strength and endurance. A new training variation that can help you hit a PR. We’re always working towards getter better and stronger.

If you’re looking for something to give you the best results, adding L-theanine to your pre-workout stack may do it.

By supporting a better recovery through its relaxation and mental regeneration effects after intense exercise, it helps create an environment that’s more suitable and efficient for recovery.

Pre Lab Pro Suntheanine®

Pre Lab Pro uses only the best form of L-theanine to give you the ultimate results. Taken pre-workout, Suntheanine® 160 mg helps to strengthen the mental aspects of exercise, supports relaxed alertness, positive mood, and cognitive clarity.

It also enhances the effects of caffeine to promote calmer, cleaner stimulation that is precision-tuned for peak athletic performance.

Compared with other forms of L-theanine and that found in tea leaves, Suntheanine® has been scientifically proven to reduce the tightening, circulation-limiting effect of caffeine to keep you working harder for longer.

In Pre Lab Pro®, this benefit allows caffeine’s ergogenic benefits to peak without interfering with other compounds that boost circulation.

Final Thoughts

For most people, especially those who struggle with high stress and engage in intense workouts, L-theanine can be a pretty enticing counterpart for caffeine. You get calm, clean stimulation with better focus and fewer side effects.

But for power-hungry results-driven athletes, it’s more. It’s a mellow ingredient added to pre-workout supplements to balance out the nasty effects of high-stim formulas. The result is better focus during your sessions and better recovery during your off days.

With Pre Lab Pro, you get all the perks of L-theanine delivered in one of the cleanest and most effective pre-workout formulas on the market, with its finely tuned dose helping you excel through your best training session yet.


  1. K Kimura, M Ozeki, LR Juneja, H Ohira. L-Theanine reduces psychological and physiological stress responses.Biol Psychol. 2007;74(1):39-45.
  2. AC Nobre, A Rao, GN Owen. L-theanine, a natural constituent in tea, and its effect on mental state. Asia Pac J Clin Nutr. 2008;17 Suppl 1:167-168.
  3. GN Owen, H Parnell, EA De Bruin, JA Rycroft. The combined effects of L-theanine and caffeine on cognitive performance and mood.Nutr Neurosci. 2008;11(4):193-198.
  4. CF Haskell, DO Kennedy, AL Milne, KA Wesnes, AB Scholey. The effects of L-theanine, caffeine and their combination on cognition and mood.Biol Psychol. 2008;77(2):113-122.
  5. FL Dodd, DO Kennedy, LM Riby, CF Haskell-Ramsay. A double-blind, placebo-controlled study evaluating the effects of caffeine and L-theanine both alone and in combination on cerebral blood flow, cognition and mood.Psychopharmacology (Berl). 2015;232(14):2563-2576.