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The Key to Vascular Pumps

Few sensations are as gratifying as getting a nice, juicy muscle pump during training. They leave your muscles looking fuller and more shapely for hours after you’ve finished training, helping give you curves in all the right places and making your clothes look that much better on you.


Today, we look at what causes muscle pumps as well as a few supplements you can take in your pre workout to get the best pumps ever!


What is a Muscle Pump?


Scientifically, a muscle pump is known as “cellular swelling.”


It is a physiological phenomenon whereby a muscle becomes engorged with blood during resistance training.


Getting a pump requires a few things to be in order. Namely, higher reps, shorter rest periods, and the right nutrition. Supplements can certainly help you get a pump easier and maintain it longer, but we’ll cover that in a little bit.


First, let’s discuss what actually happens at the cellular level when you get a muscle pump.


Under normal non-exercising conditions, blood can freely flow between your muscle fibers. As the fibers contract repeatedly during the course of a workout, the veins shuttling blood out of your muscles are pinched by the muscular contractions.


However, the arteries delivering blood to your muscles continue driving blood into them, creating an elevated amount of intramuscular blood plasma.


As a result, plasma seeps out of the capillaries and into the interstitial spaces between the blood vessels and muscle cells.


This buildup of fluid along with the accumulation of lactate (a metabolic byproduct generated by repeated muscle contractions) increases extracellular pressure, which causes a flood of plasma into the muscle cells.


The end result is blood pooling in your muscles, resulting in cellular swelling, which is lovingly referred to as “the pump.”


Now, another way to look at muscle pumps is that when you perform resistance training, the heart pumps more blood to the muscles under tension.


As this occurs, the veins that carry blood away from the working muscles are compressed as a direct result of your muscles contracting.


But, the heart is still pumping more and more blood to your muscles, which is akin to filling a balloon with water and making a very small hole at the end of it.


As the water continues to pour into the balloon, a small amount of fluid leaks out.


However, as the pressure inside the balloon increases, the balloon must expand, getting bigger and bigger.


The same thing more or less happens with your muscle cells when it gets pumped up.


As more and more blood is pumped to your muscles, intramuscular blood plasma increases so much that it starts to seep out of the capillaries and into the interstitial spaces -- the spaces between muscle cells and blood vessels.


Like we mentioned above, this fluid accumulation creates an extracellular pressure gradient, which forces plasma back into the muscle, causing blood to pool in the muscle, ending with a titanic muscle pump.


And, if having fuller more shapely muscles wasn’t enough, research indicates that cellular swelling (“the pump”) and other exercise metabolites (such as lactate) may be an independent contributor to muscle hypertrophy, not merely a cofactor (supporting player) that accompanies mechanical tension or muscle damage (the other two main mechanisms of hypertrophy).[11,12]


The Best Supplements for Vascular Pumps


High rep training, short rest periods, sodium and carbohydrates are all you “need” to get a pump. But, even then many individuals can have difficulty getting a pump or holding onto it after training is over.


Having the right supplements (at the right dosages) can make the process of getting a pump way more successful.


Here, we present the best supplements for vascular pumps, starting with...




For years, L-arginine was viewed as the “best” supplement to boost nitric oxide, blood flow, and muscle pumps. The reason for this is that within the body L-arginine is the “fuel” that drives nitric oxide production, and by supplementing with additional L-arginine you would be able to support greater stronger, longer-lasting nitric oxide production.


While this sounds good in theory, when put the test, L-arginine just didn’t deliver, unless individuals were using doses between 10-20 grams! Even then, GI distress was almost guaranteed.[1]


The reason L-arginine isn’t particularly effective for increasing nitric oxide production is that it suffers from terrible bioavailability and is subject to breakdown by the enzyme arginase.


L-Citrulline, however, is an amino acid that can navigate the treacherous path through the GI tract, bypassing metabolism by arginase, and subsequently converted to arginine where it’s then used to fuel nitric oxide production.[2] Research even confirms that L-Citrulline is superior to L-arginine supplementation for boosting plasma levels of arginine!


This results in greater vasodilation and blood flow along with increased vascularity and PUMPS!


As an added bonus, L-Citrulline is also easier on the GI tract than L-arginine, which means no GI upset.


To top it off, Citrulline has also been shown to enhance Vo2 kinetics as well as ATP production, promoting greater endurance and athletic performance during training.[4,5,6]


1UP Pre Men supplies 6 grams L-Citrulline per serving.

1UP Pre Women supplies 5 grams L-Citrulline per serving.


Agmatine Sulfate


Agmatine is a compound created from the breakdown of L-arginine that serves as a powerful neuromodulator and nitric oxide extender.



What do we mean by “extender”?


Essentially, agmatine sustains the NO-boosting effects of L-Citrulline by antagonizing the effects arginase, the enzyme that degrades arginine.[7]


But, that’s not all.


Some research also indicates that agmatine can directly enhance endothelial nitric oxide synthase (eNOS) -- the enzyme that catalyzes nitric oxide synthesis in the body![8]


The combination of these two activities not only helps boost NO production in the body, but keeps it sustained for greater amounts of time, allowing for stronger, more sustained nitric oxide production, vascularity, and pumps that won’t quit!


1UP Pre Men supplies 1 grams Agmatine per serving.

1UP Pre Women supplies 750mg Agmatine per serving.




Glycerol supplements have been used by athletes for many years.


The reason for this is that glycerol helps increase cell volumization and hydration, which boosts stamina and helps athletes resist the onset of fatigue.


However, glycerol supplements of the past suffered from three major problems:


  • They were typically in the form of glycerol monostearate, which contained a paltry amount of actual glycerol (~25% by mass at most, with the remaining 75% being composed of saturated fat)
  • Poor shelf stability, meaning they spoiled easily (due to the high fat content)
  • They inevitably clumped in the tub due to the fact that glycerol is hygroscopic, which means it attracts water (such as the moisture in the air). Undoubtedly, pre workouts with glycerol monostearate would create chunks of undissolved powder in your shaker or cemented balls of powder in your pre workout tub, which all but forced individuals to have to throw away the whole container.


These problems were solved with the emergence of a superior glycerol supplement in GlycerPump.


GlycerPump is a shelf-stable glycerol supplement containing 65% pure glycerol by weight that mixes seamlessly, will not clump, is shelf stable (meaning it won’t spoil), and won’t affect the taste of your supplements.


GlycerPump helps muscle cells pull in more water, which improves cell volumization, hydration nutrient uptake, and endurance.


You’ll also experience increased muscle fullness and dynamite “water-fueled” pumps, too!


1UP Pre Men supplies a cell-saturating 3 grams GlycerPump per serving.


Betaine Anhydrous


Betaine (trimethylglycine) is a compound that’s derived from choline (an essential nutrient for cognitive development) and is found in beets and other plants.


As a supplement, betaine gained notoriety in recent years due to research (conducted in humans) which found it may boost muscle endurance and increase strength.[9,10]


Betaine works a few different ways in the body to support performance.


Betaine helps your body produce creatine, via its methylation of the amino acid homocysteine to methionine (a building block of creatine).


Additionally, betaine also acts as an incredibly powerful osmolyte in skeletal muscle (similar to glycerol), which helps muscle cells absorb extra water, improving hydration, stamina, and fatigue resistance.[9,10]


Basically, supplementing with betaine boosts power and strength output, muscle pumps, and lean mass!


1UP Pre Men supplies the research-backed dose of 2.5 grams Betaine Anhydrous per serving.



  1. George K. Grimble; Adverse Gastrointestinal Effects of Arginine and Related Amino Acids, The Journal of Nutrition, Volume 137, Issue 6, 1 June 2007, Pages 1693S–1701S,https://doi.org/10.1093/jn/137.6.1693S
  2. Curis E., et. al; “Citrulline and the gut;”; Current Opinion in Clinical Nutrition and Metabolic Care; September 2007
  3. Bahri, S., Zerrouk, N., Aussel, C., Moinard, C., Crenn, P., Curis, E., … Sfar, S. (2013). Citrulline: from metabolism to therapeutic use. Nutrition (Burbank, Los Angeles County, Calif.), 29(3), 479–484. https://doi.org/10.1016/j.nut.2012.07.002
  4. Bailey SJ, Blackwell JR, Lord T, Vanhatalo A, Winyard PG, Jones AM. l-Citrulline supplementation improves O2 uptake kinetics and high-intensity exercise performance in humans. J Appl Physiol (1985). 2015 Aug 15;119(4):385-95
  5. Gonzales JU, Raymond A, Ashley J, Kim Y. Does L-citrulline supplementation improve exercise blood flow in older adults? Experimental physiology. 2017;102(12):1661-1671. doi:10.1113/EP086587.
  6. Suzuki T, Morita M, Kobayashi Y, Kamimura A. Oral L-citrulline supplementation enhances cycling time trial performance in healthy trained men: Double-blind randomized placebo-controlled 2-way crossover study. J Int Soc Sports Nutr. 2016;13(1):6. doi:10.1186/s12970-016-0117-z.
  7. Legaz ME, Vicente C. Endogenous Inactivators of Arginase, l-Arginine Decarboxylase, and Agmatine Amidinohydrolase in Evernia prunastri Thallus . Plant Physiology. 83;71(2):300-302
  8. Mun CH, Lee WT, Park KA, Lee JE. Regulation of endothelial nitric oxide synthase by agmatine after transient global cerebral ischemia in rat brain. Anat Cell Biol. 2010;43(3):230–240. doi:10.5115/acb.2010.43.3.230
  9. Lee EC, Maresh CM, Kraemer WJ, et al. Ergogenic effects of betaine supplementation on strength and power performance. Journal of the International Society of Sports Nutrition. 2010;7:27. doi:10.1186/1550-2783-7-27.
  10. Trepanowski JF, Farney TM, McCarthy CG, Schilling BK, Craig SA, Bloomer RJ. The effects of chronic betaine supplementation on exercise performance, skeletal muscle oxygen saturation and associated biochemical parameters in resistance trained men. J Strength Cond Res. 2011;25. doi:10.1519/JSC.0b013e318217d48d.
  11. de Freitas MC, Gerosa-Neto J, Zanchi NE, Lira FS, Rossi FE. Role of metabolic stress for enhancing muscle adaptations: Practical applications. World J Methodol. 2017;7(2):46-54. Published 2017 Jun 26. doi:10.5662/wjm.v7.i2.46
  12. Dankel SJ, Mattocks KT, Jessee MB, Buckner SL, Mouser JG, Loenneke JP. Do metabolites that are produced during resistance exercise enhance muscle hypertrophy? European journal of applied physiology. 2017;117(11):2125-35

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