Caffeine seems to be a staple in pretty much everyone’s pre-workout routine, whether it’s in the form of a cup of coffee, pills, pre-workout, or an energy drink. While the form of caffeine you’re taking does make a difference, the scientific consensus is that it can boost athletic performance.

But the tricky thing is that too little won’t get you all the benefits caffeine has to offer, and too much and you can say goodbye to a good workout.

It’s all about finding that sweet spot and how much works for your body and the type of exercise you’re doing.

If you’re not completely sold on downing a few cups of coffee or popping back a caffeine pill before your training session, we’re here to inform you about why adding in caffeine could be your best idea yet.

It’s definitely not a requirement where workouts go, but when taken at the right time and in the right dose, it could push your workout from great to off the charts incredible.

Let’s talk caffeine in pre-workout supplements—yay or nay?

What Is Caffeine?

Caffeine is one of the most widely used performance-enhancers by elite athletes, casual gym-goers, and everyone in between either in the form of a cup of coffee or a stimulant supplement. It’s a natural compound extracted from plants that elicits powerful effects on the central nervous system (CNS), acting as a powerful stimulant.

Upon ingestion, caffeine is rapidly absorbed through the gastrointestinal tract and metabolized by the liver to produce three metabolites: paraxanthine, theophylline, and theobromine 1.

The effects of caffeine hit anywhere from 30 to 60 minutes after consumption and can last anywhere from one or two hours to upwards of 8 or 9 hours. Because of its lipid solubility, it crosses the blood-brain barrier without difficulty, which is why it has such potent effects on brain function.

How Caffeine Works

There have been several mechanisms proposed for how caffeine affects athletic abilities, but the most significant one explains the effects of caffeine on adenosine; it competes with adenosine receptors in the brain to prevent fatigue and promote arousal.

Studies suggest that because caffeine can cross the membranes of nerve and muscle cells (and all tissues) so readily, the effects it elicits may actually be more neuronal than muscular 2. As such, one of the primary action sites of caffeine is the CNS.

But in addition to its effects on the CNS, it can also alter substrate utilization during exercise 3, 4. Studies find it shifts fuel substrates from relying on carbohydrates (glucose) to mobilizing free fatty acids, which may have profound impacts on performance (we'll talk more about this below).

The performance-enhancing effects of caffeine have been well-studied for decades, and we’re going to tell you everything you need to know about why caffeine should be in your pre-workout stack.

The Perks Of Caffeine For Athletic Performance

Boosts mental alertness and focus

When your brain function is on point, so is your body. In addition to boosting energy levels by stimulating your CNS and fighting fatigue, caffeine boosts mental alertness and sharpens focus to help improve reaction time and enhance your overall performance during big lifts and prolonged, intense workouts.

The reason caffeine has such a powerful effect on alertness and focus is because of its interaction with adenosine 5. Caffeine and adenosine are structurally similar molecules, which means caffeine fits into adenosine receptors and prevents adenosine from binding.

The role of adenosine is to slow down nerve cell activity along neural pathways and induce sleep and calmness, but when caffeine binds, it does the opposite and increases activity by speeding up nerve cell transmission, thus resulting in delayed fatigue and arousal.

Better endurance and cognitive function

If you’re looking to extend your endurance and perform at a higher capacity, caffeine may have some potential there. The exact mechanism as to how it does this is still debated, but there are three possibilities:

  • Increasing intracellular calcium mobilization
  • Increasing free fatty acid oxidation*
  • Functioning as an adenosine receptor antagonist in the CNS*

Some research suggests the ergogenic effects are related to boosting oxidation of free fatty acids and sparing muscle glycogen, while others remain on the side that caffeine affects endurance performance through its antagonistic effect on adenosine receptors in the brain 6.

Through the second mechanism, caffeine can delay central fatigue onset and alter ratings of perceived exertion, pain, and levels of physical strength and energy, all of which contribute to enhanced performance.

In one study, cyclists consumed 170mg of caffeine per day, participating in 150 minutes of cycling at 60% VO2max followed by five minutes of rest and a ride to exhaustion at 75% VO2max 7.

Compared to a non-caffeinated drink, participants consuming caffeine performed significantly faster and had better visual information processing after consuming caffeine.

But it may also improve endurance by increasing secretion of β-endorphins—an opioid neuropeptide and hormone synthesized in the CNS that plays an important role in pain management 8.

Studies find that caffeine consumption increases plasma β-endorphin concentrations after high-intensity exercise and their analgesic (pain-relief) properties may reduce perceptions of pain, thereby improving and prolonging endurance performance 9.

Glycogen sparing

Full glycogen stores offer a major selling point for performance and recovery. Because glycogen is needed for the growth and repair of muscles post-exercise, having an adequate supply is crucial.

But where caffeine comes in is that due to its role in the CNS, it can alter substrate utilization during exercise and spare glycogen from being used as fuel.

Specifically, studies show that it can decrease reliance on glycogen and increase dependence on free fatty acids (fat) as a fuel substrate. One study found a significant increase in intramuscular fat oxidation during cycling in subjects who consumed caffeine at a dose of 5 mg/kg 10.

If stores of glycogen are high after exercise has stopped, it leads to better recovery and greater subsequent performance.

Fat burning

The last piece we hit on is everyone's favorite—the fat-burning capabilities of caffeine.

If you’re looking to boost your burn, caffeine is one way to do it. As a powerful thermogenic agent, caffeine helps to rev metabolism and boost body temperature, allowing you to torch maximum calories and fat during your workouts.

Studies suggest that a single dose of 100mg of caffeine can increase resting metabolic rate by up to 4% in healthy individuals 11.

The net effect can be an extra burn of 150 calories daily, thus promoting better energy balance. That’s because caffeine has powerful properties that boost maximal fat oxidation, while simultaneously improving performance.

Should You Take Caffeine Pre-Workout?

The short answer is yes—if you’re looking for all that caffeine has to offer.

Taken 30-60 minutes before your workout, caffeine can provide some pretty intense benefits that you won’t want to miss out on.

With a moderate intake of caffeine, you’ll experience increased vigilance, and an improved ability to sustain your maximal endurance output.

And when it comes to weight training, most people don't necessarily use it to boost strength. Rather, it's used to enhance focus and overall arousal state, which enables you to go as hard as possible in the weight room and turn on ultimate beast mode.

But keep in mind that the upper limit for intake is around 400mg for adults, so if you exceed that you’ll likely reap the side effects rather than the benefits, which means paying attention to the dosage you’re taking is the ultimate decider of if you should take caffeine pre-workout.

How Much Caffeine Is Enough?

One of the most common mistakes people make consuming caffeine pre-workout is that they're under the assumption that more caffeine means greater gains—and it’s not true. It could actually cause the opposite effect.

As a potent nervous system stimulant, revving your nervous system with caffeine can derail your progress by causing overstimulation and the whole list of nasty effects that come with it.

So, where caffeine is concerned, you want to take the right dosage at the right time to reap maximum benefit. Available research suggests that 3-7mg/kg of bodyweight increases performance by as much as 25% 12.

Studies also consistently find that more isn’t necessarily better with caffeine. Consumption of 300 mg of caffeine didn't offer any significant improvements in performance over 200mg, but 200mg did offer a greater benefit than 100mg 13.

Pre Lab Pro offers a moderate dose of caffeine stacked with boosters and balancers for maximum workout benefits and minimal side effects.

It’s calibrated at 80mg per serving for the ideal energy boost without going overboard to unlock all the ergogenic benefits caffeine has to offer:

  • Attention and focus
  • Energy and intensity
  • Muscle strength
  • Fat-burning
  • Endurance
  • Glycogen sparing
  • Motivation

And with the addition of complementary formula ingredients—Suntheanine® L-Theanine, Ajipure® L-Tyrosine, and NutriGenesis® B-Vitamins—you max out your possibilities. You can’t get much better than this.

Final Thoughts

Caffeine isn’t a necessity in a pre-workout stack, but if you’re looking for improved focus, more energy, and better performance, adding in pre-workout supplements with caffeine can help drive your workout to an entirely new level and help you reach fitness goals you never thought possible.

That is, when you have the right pre-workout with the right ingredients and dosages, you’re guaranteed to see greater workout intensity, calmer and cleaner stimulation, laser focus, reduced crashes, jitter-free energy, and faster bounce-back and balance.


  1. ER Goldstein, T Ziegenfuss, D Kalman, et al. International society of sports nutrition position stand: caffeine and performance. J Int Soc Sports Nutr. 2010;7(1):5.
  2. LL Spriet. Caffeine and performance. Int J Sport Nutr. 1995;5 Suppl:S84-S99.
  3. MA Erickson, RJ Schwarzkopf, RD McKenzie. Effects of caffeine, fructose, and glucose ingestion on muscle glycogen utilization during exercise. Med Sci Sports Exerc. 1987;19(6):579-583.
  4. LL Spriet, DA MacLean, DJ Dyck, E Hultman, G Cederblad, TE Graham. Caffeine ingestion and muscle metabolism during prolonged exercise in humans. Am J Physiol. 1992;262:E891-8.
  5. JA Ribeiro, AM Sebastião. Caffeine and adenosine. J Alzheimers Dis. 2010;20 Suppl 1:S3-S15.
  6. MS Ganio, JF Klau, DJ Casa, LE Armstrong, CM Maresh. Effect of caffeine on sport-specific endurance performance: a systematic review. J Strength Cond Res. 2009;23(1):315-324.
  7. E Hogervorst, S Bandelow, J Schmitt, et al. Caffeine improves physical and cognitive performance during exhaustive exercise. Med Sci Sports Exerc. 2008;40(10):1841-1851.
  8. AS Sprouse-Blum, G Smith, D Sugai, FD Parsa. Understanding endorphins and their importance in pain management. Hawaii Med J. 2010;69(3):70-71.
  9. A Grossman, JR Sutton. Endorphins: what are they? How are they measured? What is their role in exercise? Med Sci Sports Exerc. 1985;17(1):74-81.
  10. D Essig, DL Costill, PJ Van Handel. Effects of caffeine ingestion on utilisation of muscle glycogen and lipid during leg ergometer exercise. Int J of Sports Med. 1980;1:86-90
  11. AG Dulloo, CA Geissler, T Horton, A Collins, DS Miller. Normal caffeine consumption: influence on thermogenesis and daily energy expenditure in lean and postobese human volunteers. Am J Clin Nutr. 1989;49(1):44-50.
  12. TM McLellan, DG Bell. The impact of prior coffee consumption on the subsequent ergogenic effect of anhydrous caffeine. Int J of Sport Nutr Exerc Meta. 2004;14:698-708.
  13. HR Lieberman, WJ Tharion, B Shukitt-Hale, KL Speckman, R Tulley. Effects of caffeine, sleep loss, and stress on cognitive performance and mood during U.S. Navy SEAL training. Psychopharmacology. 2002;164:250-61.