If you have been reading about Anti-doping testing 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.
Updated 2025-11-28. Numbers and descriptions here follow the published literature rather than marketing material.
Handling and quality assessment of cardarine reference material follow general laboratory practices for poorly characterized compounds. It typically appears as a white to off-white powder and is sparingly soluble in water but soluble in organic solvents such as dimethyl sulfoxide and ethanol. Storage recommendations usually specify a cool, dry, dark place, with long-term storage at low temperature and desiccation. Purity may be checked by high-performance liquid chromatography with ultraviolet detection, while identity is confirmed by mass spectrometry and nuclear magnetic resonance. No pharmacopeial monograph exists, so reported purity and stability depend on the supplier’s methods.
GW501516 acts as a selective agonist at PPARδ, a nuclear receptor that regulates transcription of genes involved in lipid handling and energy metabolism. Activation of PPARδ in preclinical models increases fatty acid oxidation, mitochondrial biogenesis, and exercise endurance in rodents. These effects have made the compound a subject of metabolic research and also a target for sport anti-doping rules. In humans, however, controlled studies are limited, and whether similar endurance or metabolic changes occur at tolerated exposures remains an open question. The receptor’s broad tissue distribution also means downstream effects may vary by organ and condition.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
GW501516 acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in transcription of genes related to lipid handling and energy use. Activation of PPARδ can shift skeletal muscle toward greater fatty acid oxidation in animal models, which is one reason it drew interest for metabolic disease and exercise research. The exact downstream effects depend on tissue, species, dose, and duration. Human data are sparse, so many proposed benefits remain hypotheses rather than established clinical outcomes.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Visual description for typical solid reference material. |
| Solubility | Poorly soluble in water; soluble in DMSO | Solubility depends on solvent, purity, and form. |
| Storage | Cool, dry, protected from light | Long-term storage often uses low temperature and desiccant. |
| Common analytical method | LC-MS/MS | Used for detection and quantification in biological matrices. |
| Common synonyms | GW-501516; GW501516; endurobol | Naming varies among literature, vendors, and databases. |
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
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.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
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.
==== Women's 2023 FIFA World Cup ==== The women's national football team made their World Cup debut in Australia. 20 July – Australia 1–0 Ireland (Sydney). 26 July – Canada 2–1 Ireland (Perth). Ireland eliminated. 31 July – Ireland 0–0 Nigeria (Brisbane).
== History == In 1822 the first awards were given to thirteen people by the Philadelphia Society for Promoting Agriculture entrusted by the "Corporation of the city of Philadelphia". The druggist John Scott of Edinburgh organized a $4,000 fund which, after his death in 1815 was administered by a merchant until the first award, a copper medal and "an amount not to exceed twenty dollars", was given in 1822. (At the time, $20 could buy one ox or a 12-volume encyclopedia.) Several hundred recipients have since been selected by the City Council of Philadelphia, which decides from the annual list of nominees made by the Franklin Institute.
== Chemistry == Phenylpiracetam, also known as 4-phenylpiracetam, is a racetam (i.e., a 2-oxo-1-pyrrolidine acetamide derivative) and the 4-phenyl-substituted analogue of piracetam. In contrast to piracetam and most other racetams however, phenylpiracetam contains β-phenylethylamine within its chemical structure and hence can additionally be conceptualized as a substituted phenethylamine. Phenylpiracetam is a racemic mixture of (R)- and (S)-enantiomers, (R)-phenylpiracetam (MRZ-9547) and (S)-phenylpiracetam.
=== Surgery === In severe cases, an endoscopic thoracic sympathectomy procedure can be performed. Here, the nerves that signal the blood vessels of the fingertips to constrict are surgically cut. Microvascular surgery of the affected areas is another possible therapy, but this procedure should be a last resort. A more recent treatment for severe Raynaud's is botulinum toxin. In a 2009 study of 19 patients ranging in age from 15 to 72 years with severe Raynaud's phenomenon, 16 patients (84%) reported pain reduction at rest, 13 patients reported immediate pain relief, and three had gradual pain reduction over 1–2 months. All 13 patients with chronic finger ulcers healed within 60 days. Only 21% of the patients required repeated injections. A 2007 article describes similar improvement in a series of 11 patients. All patients had significant relief of pain.
Sources: en.wikipedia.org
In construction engineering, in situ construction refers to building work carried out directly on-site using raw materials, as opposed to prefabrication, where components are manufactured off-site and assembled on-site. In situ concrete is poured at its final location, offering structural stability compared to precast construction. In wall construction, reinforcing bars are assembled first, followed by the installation of formwork to contain the poured concrete. Once the concrete has cured, the formwork is removed, leaving the wall in place. Prefabrication, in contrast, reduces on-site labor requirements and shortens project timelines, but requires precise pre-planning and involves higher manufacturing and transportation costs. In geotechnical engineering, the term in situ describes soil in its natural, undisturbed state, as opposed to fill material, which has been excavated and relocated. The differences between undisturbed soil and fill material affect how well a site can support structures, install underground utilities, and manage water drainage. Proper assessment of soil conditions is necessary to prevent issues such as uneven settling, unstable foundations, and poor water infiltration.
In response to the threat of Scuds on Israel, the US rapidly sent a Patriot missile air defense artillery battalion to Israel along with two batteries of MIM-104 Patriot missiles for the protection of civilians. The Royal Netherlands Air Force also deployed a Patriot missile squadron to Israel and Turkey. The Dutch Defense Ministry later stated that the military use of the Patriot missile system was largely ineffective, but its psychological value for the affected populations was high. Coalition air forces were also extensively exercised in "Scud hunts" in the Iraqi desert, trying to locate the camouflaged trucks before they fired their missiles at Israel or Saudi Arabia. On the ground, special operations forces also infiltrated Iraq, tasked with locating and destroying Scuds – including the ill-fated Bravo Two Zero patrol of the SAS. Once special operations were combined with air patrols, the number of attacks fell sharply, then increased slightly as Iraqi forces adjusted to coalition tactics. As the Scud attacks continued, the Israelis grew increasingly impatient, and considered taking unilateral military action against Iraq. On 22 January 1991, a Scud missile hit the Israeli city of Ramat Gan, after two coalition Patriots failed to intercept it. Three elderly people suffered fatal heart attacks, another 96 people were injured, and 20 apartment buildings were damaged. After this attack, the Israelis warned that if the US failed to stop the attacks, they would.
=== Wa === John E. Walker FRS (b. 1941). British biochemist at Cambridge University, known for studies of ATPases and ATP synthase. Nobel Prize for Chemistry (1997). Foreign associate Natl. Acad. Sci. USA. Michael Wakelam (1955–2020). British molecular biologist at Babraham Institute, Cambridge Selman Waksman (1888–1973). Ukrainian-American biochemist at Rutgers University, known for discovering streptomycin and other antibiotics. Nobel Prize in Physiology or Medicine (1952). Christopher T. Walsh (1944–2023). American biochemist at Harvard, known for work on enzymes and enzyme inhibition, and especially for his book Enzymatic Reaction Mechanisms. Member Natl. Acad. Sci. USA. James C. Wang, (b. 1938). Chinese-American biochemist at Harvard, known for the discovery of topoisomerases. Member Natl. Acad. Sci. USA Xiaodong Wang, (b. 1963), Chinese-American biochemist at the National Institute of Biological Sciences, Peking, known for his work with cytochrome c. Member Natl. Acad. Sci. USA. Otto Heinrich Warburg FRS (foreign member) (1883–1970). German biochemist at the Kaiser Wilhelm Institute for Cell Physiology (Berlin), who pioneered the study of respiration. Nobel Prize in Physiology or Medicine (1931). Arieh Warshel (b. 1940). Israeli-American biochemist and biophysicist at the University of Southern California, a pioneer in computational studies on functional properties of biological molecules. Nobel Prize in Chemistry (2013). Member Natl. Acad. Sci. USA. Foreign member of the Russian Academy of Sciences. James D. Watson FRS (foreign member) (1928–2025).
==== Revelation of Dimeric Structure and Oligomeric Structure ==== Cyclooxygenase-2 (COX-2) and microsomal prostaglandin E2 synthase-1 (mPGES-1) structures were studied using both photo-methionine (photo-activatable) and bifunctional cross linkers. Photo-methionine used in COX-2 had shown just as the bifunctional cross-linker that there was a dimeric structure which this was consistent with the crystal structure of the enzyme. In mPGES-1, the human cells (A549) had been treated with disuccinimidyl suberate (chemical cross-linker) had yielded a dimer of 33kDa and a trimer of 45kDa while it was treated with photo-methionine had yielded a dimer of the same molecular weight (33kDa) and two putative trimers (50kDa and 55kDa). Once a mPGES-1 inhibitor (MF63) was introduced; this had inhibited the formation of the 50kDa and 55kDa complexes. The dimer and trimer yielded by the chemical cross-linker was not affected by the inhibitor. Yet, photo-methionine nor disuccinimidyl suberate had not shown any protein-protein interactions between COX-2 and mPGES-1 and this could be due to various reasons. For photo-methionine; one could be due to the low incorporation at this time as it was 0.7%. So, for mPGES-1; this has 152 amino acids so only one photo-methionine would be incorporated per monomer. That also means not one specific methionine would be replaced so that results in a heterogeneous population of mPGES-1 resulting in different cross-linking.
In 2008, Guinness World Records awarded Half-Life 2 the records for "Highest-rated Shooter by PC Gamer" and "First game to feature a gravity gun". In 2009, Game Informer named Half-Life 2 the fifth-best game, writing that "Valve redefined the way first-person shooters were created". Half-Life 2 was selected by readers of The Guardian as the best game of the decade, with particular praise for the environment design. The Guardian journalist Keith Stuart wrote that it "pushed the envelope for the genre, and set a new high watermark for FPS narrative". Half-Life 2 won Crispy Gamer's Game of the Decade tournament style poll. It also won Reviews on the Run's, IGN's Best Game of the Decade and Spike Video Game Awards 2012 Game of the Decade. In December 2021, IGN named Half-Life 2 the ninth-best game of all time.
Sources: en.wikipedia.org
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.
Most methods use liquid chromatography with tandem mass spectrometry. Urine is common in anti-doping testing, and blood or plasma may be used in research.
Typical guidance is cool, dry, dark storage, often at low temperature and with desiccant. Stability data are limited, so storage conditions should be verified for each batch or supplier.
It binds and activates PPARδ, a nuclear receptor that influences gene expression related to fatty acid metabolism and energy balance. This mechanism has been studied mainly in animals and cell models, not established as a safe human therapy.