If you have been reading about Anti-doping and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-02-27. Where a claim depends on a specific study, the study is described rather than over-claimed.
Laboratory detection of cardarine typically involves sample preparation followed by chromatographic separation and mass spectrometric identification. Urine is the most common matrix for anti-doping tests, though blood and hair have also been explored. Methods can target the parent compound or its metabolites, depending on the expected window of detection. Reference standards are required for accurate quantification. Matrix effects and dilution can influence results, so laboratories use internal standards and validation protocols. The exact detection window varies with dose, route, and individual metabolism.
A common misconception is that cardarine has been proven safe for human use. In reality, human clinical data are limited, and long-term animal studies have raised concerns about cancer. Another misconception is that it is a supplement or vitamin-like compound. It is a synthetic research chemical with no approved medical indication. Scientific discussion often focuses on its mechanism and detection rather than therapeutic use. Regulatory and anti-doping literature treats it primarily as a prohibited substance.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
Laboratory detection of GW501516 commonly uses liquid chromatography coupled with tandem mass spectrometry. The method can identify the parent compound or its metabolites in urine and blood after sample cleanup. Protein precipitation, solid-phase extraction, or enzymatic hydrolysis may precede analysis, depending on the matrix. Reference standards are required for accurate quantification and confirmation. Because the compound is not approved, testing often occurs in anti-doping, forensic, or research settings rather than routine clinical care. Results are reported with limits of detection and quantification.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport | Listed by WADA as a PPARδ agonist. |
| Typical detection matrix | Urine | Most common sample for anti-doping analysis. |
| Common analytical method | LC-MS/MS | Liquid chromatography-tandem mass spectrometry. |
| Common synonyms | GW501516, GSK-516, endurobol | Names found in research and fitness contexts. |
| Typical detection window | Variable | Depends on dose, route, and individual metabolism. |
Literature on cardarine often separates receptor pharmacology from toxicology. Mechanistic papers describe PPARδ activation and gene expression changes, while safety assessments focus on carcinogenicity and species differences. Questions remain about whether rodent tumors arise through PPARδ-dependent or off-target mechanisms. Another open area is how human metabolism and exposure compare with those in animal studies. Analytical methods such as liquid chromatography–mass spectrometry are used to confirm identity in biological and product samples.
GW501516 acts as an agonist at the peroxisome proliferator-activated receptor delta, a nuclear receptor that regulates gene expression. Activation shifts transcription toward genes involved in fatty acid uptake, oxidation, and energy expenditure. The compound does not bind the androgen receptor and therefore differs from anabolic steroids and SARMs. In rodent models, this metabolic shift has been linked to increased running endurance and reduced fat accumulation. The exact downstream pathways in humans remain incompletely characterized.
Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
The compound is typically described as a laboratory compound rather than a therapeutic product. Published reports have explored its role in lipid disorders, insulin sensitivity, and exercise metabolism, yet no major drug regulator has approved it for medical use. Commercial samples sold under the cardarine name may vary in purity and identity. Analytical confirmation is therefore necessary when the material is discussed in scientific or regulatory contexts. Its classification as a prohibited substance in sport further shapes how it is studied and reported.
Cardarine is a common name for GW501516, a synthetic compound studied for its effects on lipid and glucose metabolism. It functions as an agonist at peroxisome proliferator-activated receptor delta, or PPARδ, a nuclear receptor that influences gene expression. The molecule is not a steroid, nor is it a selective androgen receptor modulator. It is also known in research and sports literature as GW-501516 and endurobol. Early laboratory work examined its metabolic activity in cell cultures and animal models.
In either case, a mixture of unbound ligands, proteins, ligand-protein complexes is passed through a column of porous beads. Ligand-protein complexes are excluded from entering the beads and exit the column quickly, while unbound ligands must travel through the beads and are retained by the column for a longer time. Ligands that elute from the column early on are therefore inferred to be bound to a protein. The automated ligand identification system (ALIS), developed by Schering-Plough, uses a combined HPLC-based SEC to liquid chromatography-mass spectrometry (LC-MS) system that separates ligand-protein complexes from unbound ligands using SEC and diverts the complex toward an LC-MS system for on-line analysis of bound ligands. Novartis' SpeedScreen uses SEC in 96-well spin column format, also known as gel filtration chromatography, which allows for simultaneous removal of unbound ligands from up to 96 samples. Samples are also passed through porous beads, but centrifugation is used to move the sample through the column. SpeedScreen is not coupled to an LC-MS system and requires further processing prior to final analysis. In this case, ligands must be freed from their targets and analyzed separately.
== References == Carpenter, Kenneth (1999). Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past), Indiana University Press; ISBN 0-253-33497-7. Deeming, D. C. and M. W. J. Ferguson (eds.) 1991. Egg incubation: its effect on embryonic development in birds and reptiles. Cambridge University Press, UK. 448pp. Glut, Donald F. (2003), "Appendix: Dinosaur Tracks and Eggs", Dinosaurs: The Encyclopedia. 3rd Supplement, Jefferson, North Carolina: McFarland & Company, Inc., pp. 613–652, ISBN 978-0-7864-1166-5 Horner, John R.; Weishampel, David B. (1996). "A comparative embryological study of two ornithischian dinosaurs - a correction". Nature. 383 (6595): 256–257. Bibcode:1996Natur.383..103H. doi:10.1038/383103b0. Mateus, I; Mateus, H; Antunes, MT; Mateus, O; Taquet, P; Ribeiro, V; Manuppella, G (1998). "Upper Jurassic theropod dinosaur embryos from Lourinhã (Portugal)". Memórias da Academia das Ciências de Lisboa. 37: 101–110. Moskvitch, Katia. "Eggs with the Oldest Known Embryos of a Dinosaur Found". BBC News. November 12, 2010. de Ricqlès, A.; Mateus, O.; Antunes, M. T.; Taquet, P. (2001). "Histomorphogenesis of embryos of Upper Jurassic theropods from Lourinhã (Portugal)". Comptes Rendus de l'Académie des Sciences, Série IIA. 332 (10): 647–656. Bibcode:2001CRASE.332..647D. doi:10.1016/s1251-8050(01)01580-4. Reisz, Robert R.; Scott, Diane; Sues, Hans-Dieter; Evans, David C.; Raath, Michael A. (2005). "Embryos of an Early Jurassic prosauropod dinosaur and their evolutionary significance" (PDF). Science. 309 (5735): 761–764.
=== Pharmacodynamics === Flmodafinil is a selective dopamine reuptake inhibitor (DRI). Its affinity (Ki) for the DAT is 4,090 nM. At the serotonin transporter (SERT), its affinity (Ki) was 48,700 nM (12-fold lower than for the DAT), and it had negligible affinity for the sigma σ1 receptor (Ki > 100,000 nM). The drug has been found to block the dopamine transporter (DAT) by 83%, to a greater extent than methylphenidate without unfavorable concomitant adrenergic effects. The drug is an atypical DRI similarly to modafinil. The affinities for the DAT of flmodafinil's enantiomers and modafinil have also been studied. The affinities (Ki) were 5,480 nM for armodafinil ((R)-modafinil), 2,970 nM for (S)-(+)-flmodafinil (JBG1-048), and 4,830 nM for (R)-(–)-flmodafinil (JBG1-049). Their affinities for the SERT and σ1 receptor have also been reported. Similarly to modafinil, (S)-(+)-flmodafinil and (R)-(–)-flmodafinil increase dopamine levels in the nucleus accumbens in animals. They have been found to increase dopamine levels by up to 150 to 200% of baseline at the highest assessed dose. These increases are much smaller than those elicited by amphetamine or cocaine. In a study comparing the wake-promoting effects of flmodafinil and modafinil, flmodafinil was found to maintain wakefulness over a significantly longer timeframe than modafinil. While the administration of neither compound resulted in sleep rebound, flmodafinil perturbed sleep architecture to a lesser degree than modafinil.
=== β+ decay and electron capture === In 1934, Frédéric and Irène Joliot-Curie bombarded aluminium with alpha particles to effect the nuclear reaction 42He + 2713Al → 3015P + 10n, and observed that the product isotope 3015P emits a positron identical to those found in cosmic rays (discovered by Carl David Anderson in 1932). This was the first example of β+ decay (positron emission), which they termed artificial radioactivity since 3015P is a short-lived nuclide which does not exist in nature. In recognition of their discovery, the couple were awarded the Nobel Prize in Chemistry in 1935. The theory of electron capture was first discussed by Gian-Carlo Wick in a 1934 paper, and then developed by Hideki Yukawa and others. K-electron capture was first observed in 1937 by Luis Alvarez, in the nuclide 48V. Alvarez went on to study electron capture in 67Ga and other nuclides.
Elevated homocysteine levels, often due to mutations in the MTHFR gene, appear to increase the risk of vertebral artery dissection. People with an aneurysm of the aortic root and people with a history of migraine may be predisposed to vertebral artery dissection. Vascular tortuosity or redundancy in young patients is associated with an increased risk of spontaneous dissection.
Sources: en.wikipedia.org
=== Biosynthesis of cysteine === Mammals biosynthesize the amino acid cysteine via homocysteine. Cystathionine β-synthase catalyses the condensation of homocysteine and serine to give cystathionine. This reaction uses Pyridoxal phosphate (vitamin B6) as a cofactor. Cystathionine γ-lyase then converts this double amino acid to cysteine, ammonia, and α-ketobutyrate. Bacteria and plants rely on a different pathway to produce cysteine, relying on O-acetylserine.
News of UDI was generally received calmly by the local citizenry, apart from some isolated incidents of passing cars being stoned in the black townships outside Bulawayo. A few expected dissenters were arrested, most prominently Leo Baron, Nkomo's lawyer, whose links with black Rhodesians and communists were seen by authorities as "subversive". Baron, the younger brother of the scientist Jacob Bronowski, was arrested nine minutes after UDI was made.
Healthy centenarians are characterized by increased serum irisin levels, whereas levels of this hormone were found to be significantly lower in young patients with myocardial infarction. These findings may prompt further research into the role played by irisin not only in vascular disorders but also in life span modulation. Fibroblast growth factor 21 (FGF-21) production has been documented as a pathway to longevity. BAT activation through cold exposure up-regulates circulating fibroblast growth factor 21 (FGF21) in humans by 37%. FGF21 improves insulin sensitivity and glucose metabolism which may partially explain its longevity promoting benefits. Under basal environmental temperatures, HDAC3 primes expression of UCP1 and the brown fat thermogenic program to ensure acute cold survival through the deacetylation and activation of PGC-1alpha. Cold exposure increases SIRT1 phosphorylation/activity in both skeletal muscle and BAT, increasing thermogenesis and insulin sensitivity through deacetylation of PGC-1alpha and other protein targets. Elevated SIRT1 levels in people are associated with increased human longevity. SIRT1 (and the other sirtuins) have many metabolic effects, but an important one for improving health and longevity is the fact that SIRT1 increases insulin sensitivity and glucose control in skeletal muscles, triggers the browning of white fat and increases BAT activity.
In biochemistry, isozymes (also known as isoenzymes or more generally as multiple forms of enzymes or isoforms) are enzymes that differ in amino acid sequence but catalyze the same chemical reaction. Isozymes usually have different kinetic parameters (e.g. different KM values), or are regulated differently. They permit the fine-tuning of metabolism to meet the particular needs of a given tissue or developmental stage. In many cases, isozymes are encoded by homologous genes that have diverged over time. Strictly speaking, enzymes with different amino acid sequences that catalyse the same reaction are isozymes if encoded by different genes, or allozymes if encoded by different alleles of the same gene; the two terms are often used interchangeably.
==== Authority to canonize ==== For several centuries, the bishops, or in some places only the primates and patriarchs, could grant martyrs and confessors public ecclesiastical honour; such honour, however, was always decreed only for the local territory of which the grantors had jurisdiction. Universal acceptance of the cultus was said to be made possible by the pope because he claimed to be the sole ruler the universal Catholic Church. Toward the end of the eleventh century the popes judged it necessary to restrict episcopal authority in this regard, and therefore decreed that the virtues and miracles of persons proposed for public veneration should be examined in councils, more specifically in general councils. Popes Urban II, Calixtus II, and Eugene III conformed to this discipline. It happened, even after these decrees, that "some, following the ways of the pagans and deceived by the fraud of the evil one, venerated as a saint a man who had been killed while intoxicated." Pope Alexander III (1159–81) prohibited his veneration in these words: "For the future you will not presume to pay him reverence, as, even though miracles were worked through him, it would not allow you to revere him as a saint unless with the authority of the Roman Church." Theologians disagree as to the full import of this decretal: either a new law was instituted, in which case the Pope then for the first time reserved the right of beatification to himself, or an existing law was confirmed.
Sources: en.wikipedia.org
== Cause == G6PD deficiency results from mutations in the G6PD gene. The G6PD gene contributes to the production of glucose-6-phosphate dehydrogenase. Chemical reactions involving glucose-6-phosphate dehydrogenase produce compounds that prevent reactive oxygen species from building up to toxic levels within red blood cells. If a reduction in the amount of glucose-6-phosphate dehydrogenase or alteration of structure occurs due to G6PD gene mutations, the enzyme loses its protective role, leading to the accumulation of reactive oxygen species and thus damaging red blood cells.
Football team equipment handler. Exhibits false humility. "The man oozed slime. He was always touching and petting his face and grimy red hair and other things that were just wrong." (Uriah Heep) Mr Armstrong – Middle school teacher and guidance counselor who has learned Demon's history and works to help him with school. (Dr Marcus Strong) Ms Annie – "Hippie" art teacher at Demon's high school who encourages his artistic abilities and encourages him in his comic strip creation. Wife of Mr Armstrong. (Annie) Vester Spencer – Owns the hardware and feed store where Demon works. He dies of complications of lung cancer, leaving Dori alone. (Francis Spenlow) Dori – Daughter of Vester Spencer whom Demon falls in love with. Both she and Demon are addicted to OxyContin and other prescription drugs. (Dora Spenlow) Jip – Dori's dog who plays a big role in her life and affections. (Jip) Rose Dartell – Fast Forward’s friend who despises Demon due to jealousy over his relationship with Fast Forward. (Miss Rosa Dartle) Mouse – Very small, fast-talking friend of Fast Forward. (Miss Mowcher)
An isotope (nuclide) is specified by the name of the element (which implies the atomic number) followed by a hyphen and the mass number (e.g. helium-3, helium-4, carbon-12, carbon-14, uranium-235 and uranium-239). When a element symbol is used, e.g. "C" for carbon, it is standard to use "AZE notation" which has the form AZE, where A is the mass number written as a superscript, Z is the atomic number written as a subscript, and E is the element symbol (e.g. 32He, 42He, 126C, 146C, 23592U, and 23992U). Because the atomic number is already fixed by the element symbol, it is common to state only the mass number in the superscript and leave out the atomic number subscript (e.g. 3He, 4He, 12C, 14C, 235U, and 239U). The letter m (for metastable) is appended after the mass number to indicate a nuclear isomer, a metastable or energetically excited nuclear state (as opposed to the lowest-energy ground state), for example 180m73Ta (tantalum-180m); a number can be appended to it to distinguish different metastable states, though this is rare in practice. The common pronunciation of the AZE notation is different from how it is written: 42He is commonly pronounced helium-four instead of four-two-helium, and 23592U uranium two-thirty-five (American English) or uranium-two-three-five (British) instead of 235-92-uranium or 235-uranium. This is not an error but the original spoken usage for isotope names, originating before AZE notation became established.
== Transportation == UPS operates over 119,000 delivery vehicles worldwide, ranging from bicycles to tractor-trailer trucks. In a long-running company policy to avoid advertisement or endorsement of a vehicle manufacturer, all external manufacturer emblems and badging are removed when a vehicle enters service (whenever possible). The typical lifespan of a UPS ground vehicle is 20–25 years (or more), lasting until the structural integrity is compromised. The company does not re-sell any of its ground vehicles. As such, retired vehicles are almost always stripped of reusable parts before being sent to be crushed/broken up. Prior to scrapping, UPS trucks and trailers have all company branding painted over and are assigned an ADA (Automotive Destruction Authorization) number and must be crushed under the supervision of UPS Automotive personnel, which records the vehicle's destruction. The only exception to this policy are vehicles taken off the road for internal company use; package cars (repainted white) are used for various purposes (typically at large hubs); older semi tractors sometimes see use as terminal tractors.
Sources: en.wikipedia.org
Yes, WADA prohibits cardarine as a PPARδ agonist. It appears on the prohibited list and can be detected in urine or blood. Athletes using it risk sanctions.
Detection usually uses liquid chromatography-tandem mass spectrometry after sample cleanup. Laboratories look for the parent compound or metabolites. The method requires validated reference standards and controls.
Legality varies by country. In many places it is an unapproved drug and cannot be legally sold for human consumption. Purchasing from online vendors carries legal and quality risks.
LC-MS/MS is common, often after sample cleanup. The assay targets GW501516 or its metabolites.