“Pump” products (nitric oxide supplements) and pre-workouts alike are a dime-a-dozen nowadays; it seems as if every sports nutrition brand has their own run-of-the-mill, stimulant-loaded concoction claiming to help you feel like a Greek god in the gym. While many pre-workouts may make you “feel” that way, they typically aren’t doing much in the way of actually enhancing your blood flow.
It's key to keep in mind that caffeine (and other CNS stimulants) work as vasoconstrictors, which can counteract the positive aspects of vasodilators. However, some caffeine is certainly still beneficial when taken prior to training (with the right ingredients accompanying it).
With that in mind, the main goal when using a pre-workout pump product is to dilate blood vessels as much as possible by increasing nitric oxide (NO) production.
If you crave skin-tearing pumps and maximum blood flow when you’re crushing the iron, you're in the right spot. Now, let's break down the science behind the top pre-workout blood flow enhancers and why one ingredient, in particular, is an absolute must.
L-ARGININE (as L-ARGININE SILICATE/AKG/HCL/MALATE)
L-arginine is an amino acid that works through several pathways to enhance NO (nitric oxide) production. In particular, L-arginine powder helps modulate nitric oxide synthase (NOS) and activate key cellular receptors such as alpha( 2 )- adrenergic receptors.  The benefits of these mechanisms include relaxation/dilation of blood vessels and enhanced insulin sensitivity, both of which encourage more efficient nutrient delivery to active muscle tissues.
L-arginine comes in several forms, such as L-arginine HCl and L-arginine AKG. Nitrosigine® is a trademarked form of L-arginine silicate that is stabilized with myo-inositol. Nitrosigine® has been a breakthrough in the bodybuilding world, delivering arginine more efficiently than ever before. Just one scoop of Rainmaker contains 750 mg of Nitrosigine®, ramping up NO production and enhancing blood flow.
VITIS VINIFERA EXTRACT (GRAPE POLYPHENOLS)
NO is a byproduct of L-arginine metabolism by an enzyme called nitric oxide synthase (NOS). Many “pump-enhancing” supplements fail because all they do is flood your body with L-arginine. However, L-arginine works best when it has the requisite cofactors available to produce nitric oxide. Since NOS is made by the body naturally, you only require small amounts to reap the most benefit from L-arginine supplementation. Without supplemental NOS, you’re wasting a lot of the L-arginine you take before hitting the gym. This is precisely why HemodrauliX includes the essential nitric oxide enzyme, NOS, giving you unmatched blood flow and muscular pumps.
The polyphenols in HemodrauliX (nitric oxide supplement) upregulate NOS so significantly that your body breaks down upwards of seven grams of L-arginine powder per serving!
HYDROMAX ®: PHARMACEUTICAL-GRADE GLYCEROL
Glycerol is the natural backbone of triglycerides (fats) and works to hydrate cells with available fluid and electrolyte - creating a muscle volumizing effect. Given that the body maintains a balance of fluids, taking in glycerol prior to training helps “swell" your muscles with water and nutrients. 
With Rainmaker you're getting a research-based amount of HydroMax ® trademarked high-potency glycerol in each serving. Other pre-workouts on the market typically utilize an inferior type of glycerol called glycerol monostearate which consists of a paltry 4-10% glycerol.
L-Citrulline is an amino acid made endogenously as part of the urea cycle. It is also found in watermelon rinds, which is why some people advocate the use of watermelon consumption prior to exercise (since it works to enhance NO-dependent signaling).
An effective dosage of pure L-citrulline is upwards of six grams taken prior to training.  Taking this amino acid prior to training has been shown to substantially increase blood arginine concentrations, and thus, elevate production of arginine-derived metabolites (e.g. ornithine, nitrite, etc.). 
Other advantages of using L-citrulline include:
- Better utilization of BCAAs during your workout
- Increased intracellular nitric oxide production which promotes vasodilation and better blood circulation
- Enhanced the body’s detoxification process
- Elevated growth hormone release after training
Are You Using the Best Nitric Oxide Supplements?
Noticing this pattern of hackneyed pre-workout formulas, Axis Labs took the effort to create an item which contains scientific dosages of ingredients proven to actually boost performance and blood flow while you train. These products are Rainmaker and HemodrauliX: NO-increasing and energy-boosting pre-workouts that will help you conquer each and every workout.
The active ingredients in Rainmaker and HemodrauliX are dosed in quantities that deliver unmatched muscular pumps, focus, strength, endurance, and energy.
- Rood-Ojalvo, S., Sandler, D., Veledar, E., & Komorowski, J. (2015). The benefits of inositol-stabilized arginine silicate as a workout ingredient. Journal of the International Society of Sports Nutrition, 12(1), P14.
- Montner, P., Stark, D. M., Riedesel, M. L., Murata, G., Robergs, R., Timms, M., & Chick, T. W. (1996). Pre-exercise glycerol hydration improves cycling endurance time. International journal of sports medicine, 17(01), 27-33.
- Orozco-Gutiérrez, J. J., Castillo-Martínez, L., Orea-Tejeda, A., Vázquez-Díaz, O., Valdespino-Trejo, A., Narváez-David, R., ... & Sánchez-Santillán, R. (2010). Effect of L-arginine or L-citrulline oral supplementation on blood pressure and right ventricular function in heart failure patients with preserved ejection fraction. Cardiology journal, 17(6), 612-618.
- Bendahan, D., Mattei, J. P., Ghattas, B., Confort-Gouny, S., Le Guern, M. E., & Cozzone, P. J. (2002). Citrulline/malate promotes aerobic energy production in human exercising muscle. British journal of sports medicine, 36(4), 282-289.