For a lot of lifters, pre-workout is a religion. It gets the blood flowing, the heart racing, and the mind and body ready to kill some heavy lifts.

And while a pre-workout may be great for resistance training because it can help to enhance focus, prevent fatigue, and extend muscle endurance, what about sports or exercise that rely mainly on cardiovascular endurance?

Whether it's a cardio day or you're training for an event, there's no denying that an energy boost would be helpful, but just how effective is pre-workout for endurance exercise?

We're diving into the research on pre-workouts to give you what you need to know about taking pre-workout before cardio. Does it work, and if so, what should you be looking for to maximize your cardio session.

Why Take A Pre-Workout Supplement

The fitness supplement industry is a multi-billion dollar industry that houses all sorts of products geared towards every single goal and need you can imagine, but for anyone looking for a major boost in their workout game, there's one supplement that constantly tops the chart—pre-workout.

It's one of the most widely consumed fitness supplements around, and while there's no consistent formula between brands, they're all designed with a similar end goal in mind.

Pre-workout supplements are a combination of ingredients designed to be consumed before training that work synergistically to enhance acute exercise performance and augment long-term training adaptations 1.

Some of the most common pre-workout ingredients that benefit performance include:

  • Caffeine: Where most pre-workout supplements are concerned, caffeine is a staple. It's one of the most widely consumed central nervous system stimulants, and studies show it exhibits benefits across a wide range of sports and activities, including endurance exercise, stop-and-go sports, and high-intensity exercise or events 2. It's also an effective ergogenic aid for improving overall performance, power, endurance, focus, and concentration 3.
  • Beta-alanine: The last thing anyone wants is to be stopped mid-workout due to muscle cramps or not having the energy to complete a set. That's where beta-alanine comes in. Beta-alanine is a beta-amino acid that functions as an intramuscular buffering protein to increase carnosine levels; carnosine helps buffer acid from the muscles, reduce lactic acid buildup, and prevent muscular fatigue 4.
  • Creatine: If you've ever stepped into a gym, you've probably heard about the muscle-boosting supplement creatine. It's a compound naturally produced in the body that plays a significant role in energy availability because of its involvement in ATP regeneration. Exogenous creatine supplementation has been shown to increase total creatine content and phosphocreatine stores, benefiting maximal power and strength, work capacity, and high-intensity exercise performance 5.
  • NOx boosters: Whether it's citrulline, arginine, or red beetroot, nitric oxide boosters are a staple in pre-workout supplements, and they're what are responsible for the infamous "pump" that you hear most lifters chasing. Nitric oxide is one of the most important signaling molecules in the human body that dilates blood vessels to increase oxygen and nutrient delivery to active muscle tissue, which improves tolerance to physical exercise and enhances recovery mechanisms 6.
  • Amino acids: Whether it's the branched-chain amino acids (BCAAs) or essential amino acids, you'll often find them in pre-workout supplements because of their role in supporting muscle growth and preventing muscle catabolism. However, there's a lot of conflicting research as to whether the branched-chain amino acids are as effective as claimed for exercise, but some research does suggest they can attenuate markers of muscle damage and enhance recovery after endurance exercise 7.

What Do We Mean By Cardio?

When it comes to cardio exercises, there's two types people can do:

1. Low-intensity steady-state cardio (LISS)

Aerobic exercises at a low-to-moderate intensity for a continuous and usually extended period at a rate of about 50-70% of maximum heart rate (HR). Compared to high-intensity exercise, LISS may be more effective for training for endurance events, as it focuses more on duration than intensity.

Exercising below the ventilatory threshold for a longer duration, as is the case with steady-state cardio, can reduce stress on the cardiorespiratory system and increase the concentration of slow-twitch muscle fibers, which helps improve aerobic metabolism.

2. High-intensity interval training (HIIT)

HIIT is by far one of the most effective forms of cardio if you're looking for fat loss because it requires more intense, short-duration work at bouts of 80-100% maximum HR. It's also shown to be beneficial for enhancing fatigue resistance, lactate threshold, race performance, and exercise efficiency.

Because HIIT works above the lactate threshold, it may also enhance the release of muscle-building, fat-burning hormones like testosterone, growth hormone, and IGF-1.

Is Pre-Workout Effective For Cardio?

While many of the ingredients in pre-workout supplements are geared towards heavy lifters, there may be some merit for cardio-lovers knocking back a scoop or two. However, that's wholly dependent on what's in your pre-workout formula.

There's a fair bit of research on specific ingredients and their benefit for endurance activities, so we're going to look at what the science says:

  • Studies show that low-to-moderate doses of caffeine (3-6 mg/kg) improve aerobic-based exercise performance, which may be mediated by a combination of increased fat oxidation and muscle glycogen sparing, central nervous system stimulation via adenosine antagonism, and/or the direct effect on skeletal muscle 8.
  • Nitric oxide has a two-fold effect on exercise performance. Studies suggest that supplementation with compounds that increase NOx production can enhance exercise-induced endothelium-derived nitric oxide synthesis and boost aerobic capacity 9. However, moderate-intensity aerobic exercise can augment endothelium-dependent vasodilation via increasing the production of nitric oxide 10.
  • The B vitamins are essential for exercise because of their role in energy metabolism via modulating the synthesis and degradation of carbohydrates, fats, and proteins 11.

This is by no means an inclusive list of the ingredients that can benefit aerobic exercise performance, but there's a fair bit of evidence to suggest that a good pre-workout with moderate levels of caffeine can be highly beneficial to exercise performance because of its effect on a few different pathways involved in exercise performance:

  1. Boost energy levels and endurance by triggering the release of adrenaline and inhibiting adenosine receptors that induce fatigue.
  2. Enhance blood flow by increasing vasodilation, which leads to greater muscle pumps and increased perfusion (nutrient delivery).
  3. Increase strength and high-intensity workload by boosting the production of adenosine triphosphate (ATP), the body's primary source of energy.
  4. Stimulate production of the neurotransmitter gamma-aminobutyric acid (GABA), which helps to increase alertness and focus.

The Best Pre-Workout Ingredients For Cardio

1. RedNite Beetroot Powder

Whether you're looking for a bigger muscle pump or better endurance, nitric oxide is the way to go. Although several compounds can enhance NOx production, beetroot powder is one of the best you can get.

It's a concentrated source of natural nitrate converted into nitric oxide to dilate blood vessels, increase blood flow, and boost oxygen and nutrient delivery to muscle tissue.

Because nitric oxide is a powerful vasodilator, the increase in blood flow and nutrient delivery can also mean enhanced capacity of muscles to contract and maintain function, which improves overall work capacity and performance.

A 2017 study published in Nutrients showed that supplementation with beetroot may improve time to exhaustion during cardiovascular exercise, which may lead to better work capacity and more gains 12.

What's more, research from the University of Exeter suggests that supplementing with compounds that boost nitric oxide levels in the body can give a significant boost to stamina during high-intensity exercise, which may be important for endurance athletes, as it can increase performance times by up to 2% 13.

2. Setria® Performance Blend

The combination of L-Glutathione + L-Citrulline in Setria® Performance Blend boosts and sustains nitric oxide levels in the bloodstream 2X as long as equivalent doses of L-Arginine or L-Citrulline alone.

Together, they're clinically shown to promote a nitric oxide NOx boost that extends into the post-workout window to reduce fatigue and accelerate recovery, and boost and maintain lean muscle mass when used in conjunction with training.

But why these two compounds? L-citrulline works to enhance NOx production, while glutathione has the ability of to stabilize and slowly release NO, which protects it from oxidative damage 14.

Because NO is a molecule that breaks down relatively quickly in the bloodstream, glutathione is required to protect it from degradation and maintain the positive effects that NO has to offer. You're getting more strength, power, speed, endurance, and overall athletic performance.

3. Natural Caffeine

Cardio isn't always the most enjoyable exercise to do, and if you're heading to the gym for fasted cardio, chances are you require something to wake you up. That's where moderate-dose caffeine comes into the picture.

But you need precision dosing for fine-tuned performance without causing overstimulation. As an adenosine antagonist, caffeine can enhance alertness and focus, and reduce drowsiness and fatigue.

Research also shows that caffeine can be an effective ergogenic aid for aerobic exercise because of its ability to alter substrate utilization during exercise. This effect is mediated via improved energy status of the muscle in the early stages of intense aerobic exercise, which may result from increased availability of fat and/or improvement in the ability of mitochondria to oxidize fat during exercise following consumption of caffeine 15.

Final Thoughts

While people have always associated pre-workout with muscle pumps and lifting, that's not the only thing it's good for.

Whether you're training for a marathon, cycling to combat the biggest mountains, or simply hitting a brutal HIIT workout after work, knocking back a scoop of a good, science-backed pre-workout can give you some pretty awesome performance benefits.

Pre Lab Pro®'s 2X NOx stack boosts and sustains blood flow to muscles to give you a clean rush that enhances strength, stamina, focus, and endurance but also extends into the post-workout period to kick-start muscle recovery.


  1. PS Harty, HA Zabriskie, JL Erickson, PE Molling, CM Kersick, AR Jagim. Multi-ingredient pre-workout supplements, safety implications, and performance outcomes: a brief review. Int. Soc. SportsNutr. 2018 Aug; 15(41).
  2. LM Burke. Caffeine and sports performance.Appl Physiol Nutr Metab. 2008;33(6):1319-1334.
  3. AC Ellerbroek, J Antonio. Effects of Pre-Workout Supplements on Strength, Endurance, and Mood. IJAHSP. 2018;17(1).
  4. RM Hobson, B Saunders, G Ball, RC Harris, C Sale. Effects of β-alanine supplementation on exercise performance: a meta-analysis. Amino Acids. 2012; 43(1): 25-37.
  5. RB Kreider. Effects of creatine supplementation on performance and training adaptations.Mol Cell Biochem. 2003;244(1-2):89-94.
  6. R Bescós, A Sureda, JA Tur, A The effect of nitric-oxide-related supplements on human performance.Sports Med. 2012;42(2):99-117.
  7. DH Kim, SH Kim, WS Jeong, HY Effect of BCAA intake during endurance exercises on fatigue substances, muscle damage substances, and energy metabolism substances.J Exerc Nutrition Biochem. 2013;17(4):169-180.
  8. KR Turley. Effects of Caffeine on Exercise Responses and Performance in Children and Youth.Am J Lifestyle Med. 2016;10(6):417-421.
  9. AJ Maxwell, HV Ho, CQ Le, PS Lin, D Bernstein, JP Cooke. L-arginine enhances aerobic exercise capacity in association with augmented nitric oxide production.J Appl Physiol (1985). 2001;90(3):933-938.
  10. C Goto, Y Higashi, M Kimura, et al. Effect of different intensities of exercise on endothelium-dependent vasodilation in humans: role of endothelium-dependent nitric oxide and oxidative stress. 2003;108(5):530-535.
  11. YN Kim, JH Hwang, YO The effects of exercise training and acute exercise duration on plasma folate and vitamin B12.Nutr Res Pract. 2016;10(2):161-166.
  12. R Domínguez, E Cuenca, JL Maté-Muñoz, et al. Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review. 2017;9(1):43.
  13. SJ Bailey, PG Winyard, A Vanhatalo, JR Blackwell, FJ DiMenna, DP Wilkerson, AMAcute L-arginine supplementation reduces the O2 cost of moderate-intensity exercise and enhances high-intensity exercise tolerance. J Appl Physiol. 2010;109(5):1394-403.
  14. P Hwang, FE Morales Marroquín, J Gann, et al. Eight weeks of resistance training in conjunction with glutathione and L-Citrulline supplementation increases lean mass and has no adverse effects on blood clinical safety markers in resistance-trained males.J Int Soc Sports Nutr. 2018;15(1):30.
  15. A Chesley, RA Howlett, GJ Heigenhauser, E Hultman, LL Spriet. Regulation of muscle glycogenolytic flux during intense aerobic exercise after caffeine ingestion.Am J Physiol. 1998;275(2):R596-R603.