Core FURY Extreme
Extreme Pre-Workout Performance Amplifier
When we first released Core FURY, we said a few things: we said that it was revolutionary, because it didn’t try to be. We said that it was formulated with clinically researched serving sizes, in a non-proprietary blend, that was made to be our most effective pre-workout supplement. We said it was amazing. We said that it couldn’t be topped. Well, we were wrong.
With Core FURY Extreme, we have somehow improved on our best, most-potent, most-concentrated pre-workout by including even more science-backed ingredients, in even bigger servings. Best of all? We have crammed every last milligram of PR-smashing Core FURY Extreme goodness into a single scoop.
No more debates about two scoops or three. Actually, no more debates period. Core FURY Extreme has every conceivable angle, mechanism, or benefit you’d want in a pre-workout covered, and we somehow managed to combine that with an amazing taste? An actual serving of creatine, one that would be enough for a creatine-only product? Yeah, we have that. One of the highest servings of citrulline, betaine, and agmatine out there? That too. What about an insane stimulant mixture, including a longer-lasting, more effective, clinically-studied form of caffeine in combination with pterostilbene? Of course.
What Core FURY Extreme doesn’t have is room for error, or a proprietary blend that masks the amount of every ingredient. This product was made by the best, for the best, to be used as a single scoop, single product arsenal against fatigue and excuses. You want the scoop? You can’t handle the scoop.
Sometimes called the “grandfather” of dietary supplements, creatine is, along with caffeine, one of the most extensively studied dietary compounds. Certainly, it is the most well-studied ergogenic aid. Generally speaking, the extensive amount of data on creatine demonstrates that it positively contributes to dilation of the vasculature, plasma-nutrient mobilization, post-workout nitrogen retention and protein synthesis, along with dose-dependently increasing contractile force through ATP (adenosine triphosphate) provision (i.e., it helps support increased strength).*
If the human body could be considered a bank account, then ATP would be the currency, and every cellular process would be like spending a little money from that account. Without making a deposit, the account runs dry (fatigue). Unfortunately, making a direct deposit to that account in the form of exogenous adenosine triphosphate is impossible, given that ATP itself is incredibly unstable. The use of supplemental creatine, however, is analogous to making a deposit in the body’s energy bank, given that creatine is eventually metabolized to ATP via several steps. In skeletal muscle, creatine is first phosphorylated into its primary derivative, known as phosphocreatine (PCr), by the muscle-specific creatine kinase, creatine kinase-MB (muscle-brain). Following the phosphorylation of creatine, phosphocreatine may then anaerobically donate a phosphate molecule to adenosine diphosphate (ADP) to form the ATP required during the initial stages of intense muscular contraction. The result is not only an increase in contractile force, but also an increase in potential type IIx (‘fast-twitch’) muscle recruitment – the type of muscle fibers which are not only traditionally associated with speed, strength, and physique, but which are also unsurprisingly the most energy-demanding fiber types. Literally speaking, creatine contributes to the building of muscle.*
Both through the ATP provision just described, as well as effects on nutrient mobilization, protein-sparing, and fluid dynamics, creatine has been consistently suggested to support both lean and muscle mass in clinical data. In the short-term, these effects are most likely the result of extra-cellular fluid retention normally associated with exogenous creatine use. In the long term, these effects are likely attributable to creatine’s collective effect on muscle metabolism. The most recent research on creatine suggests it exerts direct effects on muscle metabolism, including altering the expression of genes responsible for ribosomal assembly, attenuating the breakdown of leucine, and most famously, by expanding cell volume. Cutting through the jargon, let us just say that the amount of creatine monohydrate contained in Core FURY Extreme simply works: these servings have been shown time and again to significantly increase lean body mass and muscle volume, lower fatigue, and support performance (measured in several ways).*
Skip the gimmick, alternative forms of creatine (creatine ethyl ester, “buffered” creatines, etc) and stick to the tried and true creatine monohydrate found in Core FURY Extreme! Unlike many of the preworkouts on the market that will “sprinkle” creatine monohydrate in their proprietary blend, at 5,000 mg per one scoop serving, Core FURY Extreme uses a clinically supported serving of creatine monohydrate.
Citrulline is a non-essential, non-protein amino acid that forms during the urea cycle and forms ornithine when combined with carbon dioxide. Citrulline is also a critical source of endogenous (natural) arginine, as it is rapidly and efficiently converted to arginine in the vascular endothelium and other tissues.
Like agmatine, the other arginine pre-cursor/byproduct featured in Core FURY Extreme, citrulline’s benefits have been shown to be greater than its parent compound. While arginine undergoes direct hepatic (liver) metabolism through the enzyme arginase, citrulline bypasses hepatic metabolism entirely and it is delivered straight to the bloodstream. The result is that gut absorption and plasma (blood) bioavailability studies comparing citrulline and arginine have shown two things. First, that citrulline is less readily destroyed and has greater absorption than arginine. Second, that citrulline supplementation increases arginine levels more effectively than arginine supplementation itself.
This translates to promising results. For example, animal studies show a significant increase in anaerobic performance at a 250mg/kg/day serving of citrulline, while studies in humans implicate citrulline in both aerobic and anaerobic performance increases. As a critical part of the urea cycle, citrulline’s performance benefits are thought to be a result of its role in ammonia clearance. Citrulline is implicated in reducing the oxygen cost of muscle processes, along with increasing the rate of post-exercise ATP and phosphocreatine replenishment. As ATP and phosphocreatine are the body’s ‘exercise fuel,’ this may result in citrulline delaying time to exhaustion in aerobic and anaerobic exercise.*
Betaine (trimethylglycine) is found naturally in most living organisms. It is well known to protect non-mammalian animal life in conditions of osmotic stress (a rapid change in the amount of solute surrounding a cell), in addition to functioning as an osmolyte in mammalian (including human) tissues). Betaine is formed in cells as an oxidation product of choline and can be obtained in the diet from foods such as spinach and beets.
Though data on betaine is limited, and recent, the available literature suggests that this compound may have effects in a number of areas. Studies on betaine using servings as little as 1.25g/day and up to 5g/day for up to 14 days have shown promising results. In one study, a 2.5g/day serving was found to enhance endurance and total repetition volume for the squat, bench press, and jump squat in in healthy-exercised trained adults. A similar study using the same serving found that betaine use increased peak power and maximum peak power, along with force and the maintenance of both force and power in healthy, exercise-trained subjects.*
Perhaps more interesting, however, is a study which examined betaine’s effect on the endocrine system. This study revealed that betaine may exert an effect on several endocine processes given the proper conditions, causing the authors to hypothesize that long(er) term betaine supplementation may support the hypertrophic response to resistance training.*
Agmatine is part of a group of compounds known as polyamines, alphatic amines which play multiple physiological roles in tissue growth and differentiation, body weight increment, brain organization, molecular mechanisms of hormonal action, intracellular signaling, and extracellular communication. Agmatine itself is naturally produced in the body by the breakdown of arginine. Paradoxically, the studied effects of agmatine not only appear to mimic those of its parent compound arginine, but in many cases, surpass it. These effects include an increase in localized bloodflow (better plasma delivery), dilation of the vasculature (expanding of blood vessels), increased nutrient delivery, and a hypothesized support for the health of the hypothalamic-pituitary axis.*
The literature suggests that agmatine sulfate’s positive regulation of NO (nitric oxide) levels occur within the classical NO-eNOS (endothelial nitric oxide synthase) pathway. Like arginine, agmatine appears to increase plasma nitric oxide via functioning as a competitive inhibitor of nitric oxide synthase. As a polyamine, agmatine may also play a role in the functioning of the hypothalamic-pituitary axis (HPTA). Data in mammals have shown that polyamines are related to gonadotropin release, and in particular, promote an increased luteinizing hormone (LH) production. This positive regulation of gonadotropin is suggested to be the result of increased γ-aminobutyric acid (GABA) synthesis, a neurotransmitter critically involved in the regulation of gonadotropin secretion.*
Tyrosine is amongst a class of amino acids known as ‘non-essential’ amino acids, so called because the body can produce them endogenously, and it is therefore not essential to consume dietary tyrosine. That said, tyrosine is also what is known as a conditionally-essential amino acid; conditionally-essential because, along with glucose and ammonia, the synthesis of tyrosine additionally requires adequate levels of phenylalanine. Once synthesized, tyrosine is one of the most critical amino acids, given its prominent role as a substrate in the synthesis of the catecholamines dopamine, norepinephrine, and epinephrine, in addition to both T3 (triiodothyronine) and T4 (thyroxine) thyroid hormones.*
In studies on stress modulation, tyrosine has been suggested to reduce norepinephrine depletion and the depressant-behavioral effects normally associated with heavy physical training.* In simpler terms, tyrosine may, in certain conditions, dampen the extent to which norepinephrine is removed from the bloodstream during workouts.* In simpler terms still, tyrosine may help to mitigate the sense of depletion and fatigue felt at the end of a workout.*
Tyrosine may also play important metabolic functions, mostly related to its role in synthesizing compounds which stimulate the nervous system. While not traditionally considered a sympathomimetic amine, studies which have coadministered tyrosine and stimulants demonstrate a synergistic effect. These studies suggest that tyrosine may potentiate the effects of both endogenous and supplemental norepinephrine and its mimetics (in the case of exogenous use) with respect to lipolysis, thermogenesis, and energy expenditure. Meaning that tyrosine may play a role in assisting norepinephrine to break up triglycerides and increase body heat transiently.*
N-acetyl L-tyrosine, the form used in Core FURY Extreme, is widely believed to be a more bioavailable form of tyrosine. And, not surprisingly, the serving size contained in just a single scoop of Core FURY Extreme lines up with the provided servings in man studies on tyrosine.
Choline is an essential nutrient involved in numerous metabolic pathways, including DNA regulation and repair, protein function, and metabolism. Perhaps most importantly, the critical neurotransmitter acetylcholine is produced directly from free choline via cholinergic neurons. Acetylcholine is then responsible for a number of functions itself, most crucially as the compound which induces muscular contraction, and as the neuromodulator partially responsible for modulating risk/reward, arousal, and supporting memory.*
Choline’s essential role as a substrate for acetylcholine, and therefore brain development, is well documented in animal models. Choline’s supporting effect is particularly prominent in the hippocampus. In humans, the hippocampus is primarily involved in the consolidation of memory (taking short, episodic memory and translating it into long-term memory) and the learning of new information. Acetylcholine is a critical component in these processes, as mentioned above, and choline may therefore play a potential role in these processes as well by providing the substrate for acetylcholine synthesis.
Tartaric acid occurs naturally in the food source, while its salt derivatives (tartrate, for example) have been used as acidulants, antioxidant synergists, buffers and sequestrants. As free base choline is rapidly destroyed in metabolism, attaching a salt to enhance absorption is necessary. The bitartrate salt addition preserves choline from being destroyed during metabolism.
1,3,7-trimethylxanthine (Caffeine) and Theobromine (3,7-dimethyl-1H-purine-2,6-dione) 99%
Caffeine and its fellow xanthine and metabolite, theobromine, are some of the most widely consumed, and perhaps some of the most reviewed, psychoactive compounds. Their physiological effects in a range of areas have been well-documented, including exercise performance, information processing, alertness and mood enhancement, attention, and awareness, along with its anti-lipogenic and lipolytic abilities.
Most importantly to Core FURY Extreme, caffeine has been shown to have significant effects on exercise performance, even with ingestion in servings as small 3 to 9mg/kg/bw/day (the equivalent of 2 cups of standard coffee, for a 170lb male). In endurance training, possible explanations for caffeine’s performance-enhancing effects lie in its metabolic effects on both lean and fat tissue. It is suggested that caffeine’s potent lipolytic (the breakdown of fat tissue into fatty acids) and oxidative (the actual ‘burning’ of fat) action allow the body to utilize these sources during prolonged submaximal exercise. As a consequence, muscle glycogen is spared and available for use later in the training session. Practically speaking, this means caffeine is forcing your body to preferentially use fat tissue as a fuel source, while sparing the glycogen which gives you the full-bodied look!
In short-term exercise, both caffeine’s and theobromine’s demonstrated role in the inhibition of cyclic AMP- phosphodiesterases (PDE), adenosine receptor antagonism, and adrenoreceptor agonism come into play. These three pathways collectively stimulate lipolytic activity, boost fat metabolism, increase metabolic rate and energy expenditure, and regulate the body’s thermogenic activity. The practical results of activating these pathways are increases to the contractile force of both cardiac and skeletal muscle (harder flexion), an increase in energy expenditure (freeing up more caloric energy to be used in contraction), dilation of vasculature (better blood flow), and improvements to both nitrogen retention and skeletal muscle protein synthesis (key components to muscle building).
In Core FURY Extreme, we have included a per-serving amount of caffeine and theobromine that is neither excessive, nor arbitrary, but that instead reflects the servings used in clinical research.
Niacin, also commonly known as nicotinic acid, has been demonstrated to exert potent effects on lipid metabolism; and a significant body of literature exists, focusing on its role as a therapeutic target in that context. In addition to playing a role in supporting healthy HDL cholesterol levels, and rapidly and dose-dependently inducing a decrease in the concentrations of plasma triglycerides, niacin is a powerful vasodilator.
PURENERGY™ (Caffeine Pterostilbene Complex):
PURENERGY™ is a highly interesting, novel new dietary ingredient created by combining caffeine (at a 43% proportion) with pTeroPure, a 99% pure all-trans pterostilbene (at 53% proportion).
Pterostilbene is, in turn, itself a highly interesting compound, and the subject of considerable excitement and clinical research within the sports community. Found in small concentrations in blueberries and grapes, pterostilbene is a dimethylated version of the well-known compound resveratrol, and as a consequence, appears to share many of its beneficial physiological effects. Pterostilbene in addition has been hypothesized to exert unique effects in the human body through both genomic and enzymatic pathways, including functioning as a potent antioxidant, as well as playing a role in the regulation of glycolytic/gluconeogenic enzymes such as hexokinase, glucose-6-phosphatase, and fructose-1,6-bisphosphatase.
In combination as PURENERGY™, caffeine and pterostilbene have been the subject of a single, but promising, human trial. The results from this trial demonstrated:
- PURENERGY™ delivers almost 30% more caffeine into the blood than ordinary caffeine.
- The rate of caffeine absorption is significantly slower with PURENERGY™, by about 30% as compared to ordinary caffeine
- The half-life of caffeine from PURENERGY™ is extended significantly by about 25% over that of ordinary caffeine.
- At 4 hours, there was 45% more caffeine from PURENERGY™ compared to ordinary caffeine alone
- At 6 hours, there was 51% more caffeine from PURENERGY™ compared to ordinary caffeine alone.
- At 6 hours, subjects taking PURENERGY™ supportted significantly less fatigue and greater concentration compared to baseline.* Ordinary caffeine did not.
- At 6 hours, subjects taking PURENERGY™ supported improved energy, alertness and focus compared to baseline.* Ordinary caffeine did not.
- Coupled with a lack of adverse events seen in the trial, PURENERGY™ may represent a significant leap forward in the dietary supplement field.
Hordenine (N,N-dimethyltyramine) HCl:
Hordenine is one of the most favored stimulant ingredients in bodybuilding circles, and has been for some time. Users rave about hordenine, due to its structural similarity with several potent nootropics and stimulants.*
Though limited, some animal research suggest that hordenine may modulate certain brain and nervous system processes, and perhaps regulating the body’s release of and response to noradrenaline.
Synephrine is a naturally-occurring alkaloid with adrenergic agonist activity, structurally related to epinephrine, norepinephrine, ephedrine, and other compounds with a phenethylamine base structure. Despite its chemical similarity to these compounds, synephrine in its various isomers exerts unique effects on adrenergic receptors, in particular, and the human body, in general.
Synephrine exists in three isomer forms: para-, meta- and ortho-synephrine. The molecular changes between the three isoforms are minute, but even this small change results in significant alterations to each isomer’s physiological and pharmacokinetic profile. Two of synephrine’s isomers, both p- and m-synephrine, have been shown to naturally occur in mammals (in low concentrations).
As a sympathomimetic, synephrine has been the subject of numerous trials, assessing its effects on weight management, thermogenesis, metabolic rate, and caloric expenditure. In a double-blind, randomized, and placebo-controlled trial involving 10 healthy individuals, the p-synephrine isomer was administered at a 50mg serving, both alone, and in combination with hesperidin and naringin. The authors measured resting metabolic rate (RMR), blood pressure, and heart rate, along with subjective feelings of mood and energy, at baseline, and at 45-mintues and 75-minutes after ingestion. The authors reported a significant increase in RMR in each of the supplement groups, relative to placebo.*
In combination with caffeine, synephrine’s metabolic effects appear to be potentiated – with rates of fatty acid liberation, heart rate, metabolic rate, and fatty acid oxidation increased.
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What's in Core Nutritionals FURY Extreme
Directions For FURY Extreme: Mix 1 scoop with 8-16 ounces of water and consume approximately 15 minutes prior to your workout. For enhanced performance, stack with 1 serving of Core ABC and 1 serving of Core PUMP.
Warnings: This product is only intended for use in healthy adults 18 years of age or older. Pregnant or nursing women should not use this product. Consult your healthcare provider before using this product, especially if you are taking any prescription, over the counter medication, dietary supplement product , or if you have any pre-existing medical condition including but not limited to: high or low blood pressure, cardiac arrhythmia, stroke, heart, liver, kidney or thyroid disease, seizure disorder, psychiatric disease, diabetes, difficulty urinating due to prostate enlargement or if you are taking a MAOI (Monoamine Oxidase Inhibitor) or any other medication. Discontinue use and consult your health care professional if you experience adverse reaction to this product. Do not exceed recommended serving. Do not use in combination with caffeine or any stimulants, including but not limited to, coffee, tea, soda, and other dietary supplements or medications. Do not use under extreme conditions of heat, sleep deprivation, extreme cardiovascular exertion or dehydration. Do not combine with alcohol. Do not use if safety seal is broken or missing. Keep out of reach of children.