The short version of anti-doping fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-02-01 and is reviewed periodically as new material appears.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
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.
Activation of PPARδ changes transcription of genes involved in fatty acid transport, mitochondrial function, and skeletal muscle fuel preference. In rodent studies, pharmacological PPARδ activation was associated with increased endurance and altered body composition. These findings generated interest in performance enhancement, but species differences and study designs limit direct extrapolation to humans. Small human trials were conducted in the 2000s and later discontinued. The extent to which cardarine produces similar metabolic or performance effects in people remains an open question.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport; not approved as medicine | Listed by WADA at all times. |
| Common synonyms | GW501516, GW-501516, endurobol | Cardarine is a colloquial name. |
| Typical analytical method | LC-MS/MS | Detects parent compound and metabolites. |
| Common test matrix | Urine | Blood and dried blood spots also possible. |
| Legal classification | Varies by country | Often treated as unapproved drug or research chemical. |
Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
Human trials of GW501516 were small and short in duration. They examined lipid levels, glucose handling, and other metabolic markers, but the programs were halted after the animal cancer findings. No approved therapeutic product exists, and published human data are insufficient for establishing long-term safety. Reports of use for athletic performance come mainly from non-clinical settings and cannot be verified through controlled trials. Independent testing of products sold as cardarine has found inconsistent purity and labeling.
Despite finishing bottom of the leaderboard, they made it through to the following week, where Collins showed notable improvement during her routine to Celine Dion's "It's All Coming Back to Me Now, however she suffered a fall towards the end of the performance, catching her toe pick on the ice and ultimately falling flat on her face, causing her significant injuries and enduring damage to her knee. Despite the fall, the couple received 16.5 points out of 40.0, their highest scores of the competition and subsequently progressed to the next week. For week five, Collins skated to "Look What You Made Me Do" by Taylor Swift, whilst dressed as the Evil Queen for that week's Fairy Tale themed episode. She scored 13.5 points out of 40.0, after which she broke down in tears and admitted her loss of confidence after her fall the previous week. Despite finishing bottom of the leaderboard again, Collins was voted through by the public. In week six, they skated to "Survivor" by Destiny's Child, with Collins attempting the three required elements for that week's routine. They scored 15.5 points out of 40.0, before ending up in the skate-off for the first time against Ryan Sidebottom and his professional partner Brandee Malto. After their skate-off performance to Whitney Houston's "Queen of the Night", which Collins admitted they "hadn't practiced for weeks", they became the fifth couple to be eliminated from the competition, after the judges unanimously voted to save Sidebottom and Malto, ultimately finishing in eighth place.
==== Glycosaminoglycans ==== Topical glycosaminoglycans supplements can help to provide temporary restoration of enzyme balance to slow or prevent matrix breakdown and consequent onset of wrinkle formation. Glycosaminoglycans (GAGs) are produced by the body to maintain structural integrity in tissues and to maintain fluid balance. Hyaluronic acid is a type of GAG that promotes collagen synthesis, repair, and hydration. GAGs serve as a natural moisturizer and lubricant between epidermal cells to inhibit the production of matrix metalloproteinases (MMPs).
=== Places === Snowcap Creek, a tributary of the Lillooet River, British Columbia, Canada; see List of tributaries of the Fraser River Snow Cap, Großer Arber, Germany; an air operations center radar station of the German Air Force
Sources: en.wikipedia.org
=== Role in tumor growth === Endothelial progenitor cells are likely important in tumour growth and are thought to be critical for metastasis and the angiogenesis. A large amount of research has been done on CFU-Hill bone marrow-derived putative EPCs. Ablation of the endothelial progenitor cells in the bone marrow lead to a significant decrease in tumour growth and vasculature development. This indicates that endothelial progenitor cells present novel therapeutic targets. Inhibitor of DNA Binding 1 (ID1) has been used as a marker for these cells; this allows for tracking EPCs from the bone marrow to the blood to the tumour-stroma and even incorporated in tumour vasculature. Recently it has been found that miRNAs regulate EPC biology and tumour angiogenesis. This work by Plummer et al. found that in particular targeting of the miRNAs miR-10b and miR-196b led to significant defects in angiogenesis-mediated tumor growth by decreasing the mobilization of proangiogenic EPCs to the tumour. These findings indicate that directed targeting these miRNAs in EPCs may result in a novel strategy for inhibiting tumor angiogenesis. Studies have shown ECFCs and human umbilical vein endothelial cells (HUVECs) to have a capacity for tumor migration and neoangiogenesis even greater than that of other CD34+ hematopoietic cells when implanted in immunodeficient mice, suggesting the endothelial progenitors play a key role, but further supporting the importance of both cell types as targets for pharmacological therapy.
== Target organelle == In contrast to IP3 and cyclic ADP-ribose which predominantly mobilize Ca2+ from the neutral and abundant endoplasmic reticulum (ER) store, NAADP selectively targets acidic Ca2+ stores — usually less abundant than the ER but with a pivotal role that belies their size. This paradigm shift away from the ER derives from seminal studies, again in sea urchin egg, that showed NAADP-mediated Ca2+ release was sensitive to agents that target acidic organelles (e.g. bafilomycin A1) but was less sensitive to ones that interfere with ER Ca2+ storage (e.g. thapsigargin).
=== Research === Two live samples of variola major virus remain, one in the United States at the CDC in Atlanta, and one at the Vector Institute in Koltsovo, Russia. Research with the remaining virus samples is tightly controlled, and each research proposal must be approved by the WHO and the World Health Assembly (WHA). Most research on poxviruses is performed using the closely related Vaccinia virus as a model organism. Vaccinia virus, which is used to vaccinate for smallpox, is also under research as a viral vector for vaccines for unrelated diseases. The genome of variola major virus was first sequenced in its entirety in the 1990s. The complete coding sequence is publicly available online. The current reference sequence for variola major virus was sequenced from a strain that circulated in India in 1967. In addition, there are sequences for samples of other strains that were collected during the WHO eradication campaign. A genome browser for a complete database of annotated sequences of variola virus and other poxviruses is publicly available through the Viral Bioinformatics Resource Center.
Sources: en.wikipedia.org
== Lewis bases == A Lewis base or electron-pair donor is a molecule with one or more high-energy lone pairs of electrons which can be shared with a low-energy vacant orbital in an acceptor molecule to form an adduct. In addition to H+, possible electron-pair acceptors (Lewis acids) include neutral molecules such as BF3 and high oxidation state metal ions such as Ag2+, Fe3+ and Mn7+. Adducts involving metal ions are usually described as coordination complexes. According to the original formulation of Lewis, when a neutral base forms a bond with a neutral acid, a condition of electric stress occurs. The acid and the base share the electron pair that formerly belonged to the base. As a result, a high dipole moment is created, which can only be decreased to zero by rearranging the molecules.
Within a three months period in 1980, at least ten Libyan dissidents were murdered in Europe, including ex-diplomats, ex-army officers, businessmen, journalists, and student activists in disparate locations such as London, Greece and Austria. At least eleven more were assassinated in 1981. In 1984, Gaddafi was tricked by Egyptian President Hosni Mubarak into announcing the assassination of former Libyan Prime Minister Abdul Hamid al-Bakkoush in Cairo; Bakkhoush not only turned up alive but held a press conference with Egypt's Interior Minister. In 1979, Gaddafi created the Islamic Legion, through which several thousand Africans were military trained. Libya had sought to improve US relations under President Jimmy Carter, for instance by courting his brother, businessman Billy Carter, and paying for the services of former CIA officers, but in 1979 the US placed Libya on its list of "State Sponsors of Terrorism". Relations were further damaged when a demonstration torched the US embassy in solidarity with the perpetrators of the Iran hostage crisis. Libyan fighters began intercepting US fighter jets flying over the Mediterranean, signalling the collapse of relations between the countries. Italian media have alleged that the Itavia Flight 870 was shot down during a dogfight involving Libyan, United States, French and Italian Air Force fighters in an assassination attempt by NATO members on a Libyan politician, perhaps even Gaddafi, flying in the same airspace.
The two substrates of this enzyme are ethyl (S)-3-hydroxyhexanoate and oxidised nicotinamide adenine dinucleotide phosphate (NADP+). Its products are ethyl 3-oxohexanoate, reduced NADPH, and a proton. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is ethyl-(S)-3-hydroxyhexanoate:NADP+ 3-oxidoreductase. This enzyme is also called 3-oxo ester (S)-reductase.
Its quadrupole moment causes line broadening. Used in metabolic and biochemical studies of chemical equilibria. 19F, spin-1/2, relatively commonly measured. Sensitive, yields sharp signals, has a wide chemical shift range. 31P, spin-1/2, 100% of natural phosphorus. Medium sensitivity, wide chemical shift range, yields sharp lines. Spectra tend to have a moderate level of noise. Used in biochemical studies and in coordination chemistry with phosphorus-containing ligands. 35Cl and 37Cl, spin-3/2, broad signal. 35Cl is significantly more sensitive, preferred over 37Cl despite its slightly broader signal. Organic chlorides yield very broad signals. Its use is limited to inorganic and ionic chlorides and very small organic molecules. 43Ca, spin-7/2, relatively small quadrupole moment, moderately sensitive, very low natural abundance. Used in biochemistry to study calcium binding to DNA, proteins, etc. 195Pt, used in studies of catalysts and complexes. Other nuclei (usually used in the studies of their complexes and chemical bonding, or to detect presence of the element):
Sources: en.wikipedia.org
Legal status varies by country. It is not approved as a medicine, and it is prohibited in sport. Some jurisdictions restrict import, sale, or possession.
Laboratories use liquid chromatography-tandem mass spectrometry to detect GW501516 and its metabolites. Urine is commonly tested, and testing can occur in and out of competition.
No, cardarine is not a SARM. It is a PPARδ agonist, which acts on a different receptor. The two classes are often confused in online discussions.
Cardarine is a common name for GW501516, a synthetic PPARδ agonist. It is not a steroid or a selective androgen receptor modulator. It was developed and studied as a research compound for metabolic pathways.