I've mentioned this before in previous articles but it appoints that can't be driven home enough. If your goal is strength and CNS stimulation, you need a pre-workout formula with the stimulants: caffeine if not ephedrine, and the other evils. No denying they work.
BUT stimulants tend to vasoconstrict. So while they lend the CNS kick for a better lift, the vasoconstriction kills your pump. Conversely using a vasodilator of note will give you much pump, delivering growth factors and nutrients to the muscle BUT end little to no aid to your "hoist". Honestly, it boils down to are you a lifter or a builder stop trying to ride two saddles at once. It's never worked.
Pre-workout aside, L-Citrulline can also preserve muscle tissue for those dieting down (for natties this is esp. important as this is typically the reason for highly anabolic PED's). "If you take a hefty portion of the amino acid L-citrulline just before going to sleep at night, it might help you to maintain muscle mass even though you're on a low-cal diet and are aiming to lose fat..."
Amino Acids. 2013 Nov;45(5):1123-31.
Now as we reach for the right Citrulline supplement, we have to be careful. Vince Comtois of ATP supplements is a researcher extraordinaire and raised the point:
"Several companies opt to use Citrulline Malate rather than pure L-Citrulline in their formulas. [They] contain a mixture of L-Citrulline and Malic Acid. Thus, Citrulline Malate contains 50% less L-Citrulline per serving. In the end, Citrulline Malate is much less effective in increasing blood arginine which decreases the efficiency of vasodilatation (Pump)..."
"L-Citrulline [is] hygroscopic (water-attracting) which results in a caking/clumping effect. However, this effect does not diminish the quality of the L-Citrulline. Glycerol also has this same hygroscopic quality, compounding the caking/clumping issue..."
So no panicking if your high-end formula seems to clump it actually is a sign of ingredient quality.
Personally I am very much a volume/ pump trainer akin to the physique trainees of the Gironda/Arnold era. The more I feel a movement and build the pump, the more satisfying the workout (and if I may- the kinder to joints and connective tissue . .at 50+ a real gift). I use ATP's E-NOS 2.0 for its' mix of L-Citrulline, Glycerol, Arginine esters, and Beta-alanine (which offers those couple extra reps each set).
So if pump and circumstance are your goals, this is your gatekeeper supplement.
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