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Designer Supplements N.O. Limits

180 Capsules

Designer Supplements N.O. Limits Through the promotion of blood flow and positive nutrient partitioning, Nitric Oxide (NO) has found an elite place amongst bodybuilding and fitness enthusiasts looking to improve their physique.

: Designer Supplements
: 180 Capsules
: 6 Capsules
: 30
: Anti-Estrogen and PCTs
Product Not Currently Available

Skin-Tearing Pumps and Enhanced Nutrient Uptake!

Through the promotion of blood flow and positive nutrient partitioning, Nitric Oxide (NO) has found an elite place amongst bodybuilding and fitness enthusiasts looking to improve their physique. While some products merely do an adequate job of accomplishing this goal, the ideal NO product can produce a proverbial “skin-tearing” pump that provides the perfect physical and mental motivation for training; a product that makes you feel unstoppable in the gym. It is with this concept in mind that Designer Supplements introduces N.O. Limits, the evolutionary next step in Nitric Oxide signalling products. Avoiding the trappings of unnecessary ingredients and proprietary blends.

N.O. Limits is comprised of four primary ingredients with attached ethyl esters to enhance effectiveness, plus antioxidants to enhance safety and long term efficacy. Additionally, while the pump alone may be impressive enough for some, N.O. Limits combines Arginine Ethyl Ester with Lysine Ethyl Ester for the first time ever in an NO product to maximize natural growth hormone (GH) secretion.

Now, before we explain exactly why increased blood flow, increased nutrient uptake, long-lasting pumps, and maximized GH secretion can make an athlete feel as though there are N.O. Limits to what he or she can do, it is first our duty to explain how.

N.O. Limits, N.O. Nonsense

Traditional NO-boosting products use the NO precursor L-Arginine or a varied structure of this amino acid in order to provide substrate for NO conversion. N.O. Limits not only provides the substrate using the new ethyl ester technology, it also utilizes compounds that control Nitric Oxide production while also providing anti-oxidants to control free radical release that Nitric Oxide and physical exercise can cause. By paying close attention to these details, N.O. Limits aims to not only prolong the efficacy of nitric oxide in users, but also potentially correct the fact that NO-boosters do not work in all users.

What is Nitric Oxide?

Nitric Oxide (NO) is a highly important signalling molecule in the body. Interestingly, it is a gas, and even more interesting is that it is also a free radical. While major research has recently indicated that NO is intimately related to brain, stomach, kidney, liver and lung function, the major interest bodybuilders and athletes have in NO is that it regulates blood flow and can influence nutrient uptake.

Initially referred to as the Endothelium-Derived Relaxing Factor (EDRF), NO achieves its most tangible effect by causing the outer wall (the smooth muscle) of the blood vessel to relax and dilate. More specifically, NO binds to an enzyme known as guanylyl cyclase which catalyzes the conversion of Guanosine Triphosphate (GTP) to 3’,5’-cyclic Guanosine Monophosphate (cGMP). It is the cGMP that signals the smooth muscle to relax.

The net result of this reaction allows more nutrient-rich blood to travel through the artery thereby causing the effect commonly known as the “pump”. Not only is the pump mentally motivating, but there is also speculation that it may promote increased protein synthesis in the stressed muscle, and may increase creatine synthesis. On a similar note, very early scientific research into Arginine itself suggested that it was required for creatine synthesis, possibly due to it’s effect at raising Nitric Oxide. More recent research also suggests that NO is involved in satellite cell proliferation which is one of the preliminary processes that must occur to initiate muscle repair and growth.

With regards to nutrient uptake, it was initially suggested that NO promoted nutrient uptake independently of the insulin signalling pathway, maybe as part of insulin-independent nutrient uptake (from muscle contractions, such as physical exercise). However more recent research indicates that nutrient uptake promoted by NO may be independent of both the insulin and contraction signalling pathways. While still speculative, this mechanism is extremely exciting as it suggests that NO-boosting products are more than just superficial and may actually help promote muscle growth beyond assistance in mental motivation to break through plateaus.

Nitric Oxide Synthesis

NO is typically created in the endothelium (a lining of the blood vessel) as a by-product of Citrulline production after Arginine combines with oxygen with the help of a group of enzymes called Nitric Oxide Synthase or NOS (there are three identified types of NOS depending upon where the conversion is taking place). This is referred to as the L-Arginine- Nitric Oxide Pathway. Keeping this mechanism in mind, providing the body with more substrate in the way of Arginine can help boost this reaction and as history has shown, any good NO-boosting product fundamentally uses this as a basis for their product. While this is all fine and dandy, for those who like to think outside of the box and look further into what is actually occurring within the body, a superior formula can be created. In order to accomplish this, the amino acid Citrulline can not be ignored. Studies indicate that not only does citrulline appear to boost levels of Arginine in the body, it may also boost levels higher than taking Arginine itself. While this mechanism has not yet been fully elucidated, it may very well be due to the fact that Arginine appears to be heavily metabolized in the intestine and by the liver before it has full access to the bloodstream.

Citrulline vs. Ammonia

Citrulline is an amino acid that is metabolized in the kidneys in order to create Arginine which can then be made available to other tissues throughout the body. In reality, the fact that Citrulline is the rate-limiting factor for Arginine synthesis in the kidneys11 makes it almost illogical to produce an NO-boosting formula that does not include a source of Citrulline. In addition to this fact, Citrulline’s relationship to Arginine and Ornithine is extremely significant in that all three are important intermediates in the process known as the Urea cycle; a process which occurs in the kidneys and is critically important for regular body function through removal of highly toxic ammonia from the blood stream.

Ammonia is a by-product of nitrogen breakdown that accumulates due to a variety of bodily processes, including amino acid digestion. By increasing metabolic rate and therefore amino acid breakdown, physical exercise produces a great deal of ammonia which may build-up. It is actually this build-up of ammonia and subsequent change in cellular pH that is partially responsible for the “burn” experienced during intense exercise or high-rep sets. When the Urea cycle is unable to keep up with nitrates, their build-up induces a metabolic acidosis which can inhibit energy production, reduce recovery, and hinder athletic performance significantly. Citrulline helps negate this effect by promoting the kidney to reabsorb bicarbonates which acts as a buffer against lactic acidosis, thereby helping to avoid fatigue and promoting endurance. By supplying Arginine, Citrulline and Ornithine together, N.O. Limits ensures that there are no rate-limiting factors for this process and keeps the cycle going in overdrive in order to supply more NO for positive effects on the “pump”, endurance, and nutrient uptake.

Folic Acid

Folic acid has been shown to enhance the NOS isoform found in the endothelium (called ‘eNOS’). It is thought to do this via its effects on a major co-factor involved in arginine-to-Nitric Oxide conversion, tetrahydrobiopterin (BH4). Folic acid is a major component for NO signalling, and a deficiency can result in many problems, including vascular dysfunction.

Arginine, Lysine & Growth Hormone Secretion

Lysine is included in N.O. Limits due to its ability to promote human Growth Hormone (hGH) secretions, specifically when combined with Arginine. In a step never taken by any other company before, N.O. Limits uses this combination in their ethyl ester form for increased bioavailability. As an added benefit, research also indicates that Arginine appears to be capable of reducing the inhibitory action IGF-1 has on hGH release. As hGH is part of many metabolic functions of the body that relate to anabolic activity, this fact poses further exciting possibilities that a well designed NO-product might be more than “just the pump.” While questions may be raised about how effective or significant this rise in hGH may be, its effects upon stimulating protein synthesis, bone strengthening and lipolysis (fat burning) are certainly welcomed.

Glutathione and NO Production

As stated earlier, due to NO being a free radical, including antioxidants in an NO-boosting formula is an excellent idea.

Glutathione is the body’s best natural anti-oxidant and unfortunately, NO production and nitrate disposal diminish the body’s glutathione reserves18. Additionally, it is speculated that the oxidative stress induced by NO production causes further glutathione depletion. It is theorized that as glutathione levels drop, the body’s own NO production capacity lowers, inducing tolerance to nitrates. This process may explain why some people simply do not respond to NO-boosting products and why others only respond for a few days before becoming tolerant. While other products either ignore this fact or try circumventing the effect in a roundabout manner, N.O. Limits goes straight to the source by supplying a compound that supports the body’s glutathione producing capabilities - Cysteine - in the form of N-Acetyl-Cysteine (NAC). In addition to this, the acetyl group can be donated from NAC to be plugged into the Krebs Cycle where it can go towards ATP production.

Free Radicals

In addition to glutathione depletion, physical exercise increases free radical generation as by-products of metabolic processes that are stepped-up to meet demand for energy. Unfortunately, NO and one of the primary free radicals provoked by exercise, superoxide, have strong attraction and their combination produces peroxynitrite species. Peroxynitrite, along with other free radicals, exert detrimental effects on protein synthesis, insulin signaling and general health while also stimulating synthesis of the chemical Asymmetric Dimethylarginine (ADMA), which inhibits the eNOS isoform. While all of this may sound negative, beneficial effects are noted as long as NO production is kept in balance with the increase in free radicals. While the body is quite adept at doing this on its own, N.O. Limits offers additional assistance through the addition of proven anti-oxidants.

N.O. Limits caters to the balance with the inclusion of NAC. Additionally, for those who desire that extra level of assurance, R-Alpha Lipoic Acid in the form of Glucophase XR or the soon-to-be-released Insutrol can prove to be a useful adjunct in that it may promote activity of the NOS in addition to its well studied anti-oxidant effect against free radicals.

  • Promoting workout “pumps”
  • Improving blood flow
  • Increasing nutrient uptake
  • Maximizing hGH release
  • Positive Mental motivation

N.O. Limits can be stacked with XCEED to form the perfect pre-workout cocktail that will maximize your performance as you train, and promote your recovery as you rest. The addition of Replenish post workout along with Glucophase XR confers added benefit in terms of nutrient partitioning, active recovery, and maximal cellular signalling to ensure the best results of each and every workout. Going to the gym should be about maximum.

SKU: 791851333569 Brand: Category: Purpose:

Supplement Facts

Serving Size: 6 Capsules  
Servings Per Container: 30  
Amount Per Serving  
L-Arginine Ethyl Ester DiHCL - 1.5g  
L-Lysine Ethyl Ester DiHCL - 1g  
L-Ornithine Ethyl Ester DiHCL - 500mg  
Citrulline Ethyl Ester HCL - 500mg  
NAC(N-Acetyl Cysteine) - 500mg  
Folic Acid - 400mcg  


As a dietary supplement, take 6 capsules approximately 30 to 45 minutes prior to your workout. Take with at least 12-16 ounces of water and continue to drink fluids prior to and during your workout.


For use as a dietary supplement only, by healthy adults the age of 18 and over. Do not exceed the daily recommended serving size, and do not use for more than 60 consecutive days. Use this product responsibly; always consult a physician before using this or any other dietary supplement.

* No claims found on this web page or in print have been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. No claim or opinion about weight loss, bodybuilding or general health on this web page is intended to be, nor should be construed to be, medical advice. Please consult with a healthcare professional before starting any weight loss diet or exercise program.

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