Cardarine (GW501516):
A Comprehensive Overview

What is Cardarine?

Cardarine, also known as GW501516, is particularly well-known in the bodybuilding community as an effective "fat burner." It stimulates the body to use fat as an energy source instead of relying on carbohydrates or muscle tissue. This improves fat burning, increases endurance, and leads to better energy efficiency in muscles.

Cardarine is not a SARM but belongs to the class of PPAR-Delta agonists (Peroxisome Proliferator-Activated Receptor-Delta).

Cardarine mechanism of action

Binding to PPAR-δ

After ingestion, Cardarine binds to PPAR-δ receptors and activates them. These receptors can be found in many areas of the body. [R]

The benefits arising from the activation of the receptor are presented below:

Increased Fat Burning

The activation of the PPAR-δ receptor causes the liver to switch its energy supply from glucose to fatty acids. Thus, fat burning increases. A Phase 1 study found that Cardarine reduced liver fat content by 20% [R]. This brings additional benefits: Cardarine can lower blood sugar levels, which improves insulin sensitivity and reduces the risk of developing Type 2 diabetes. [R]

Improved Endurance and Energy Efficiency in Muscles

Cardarine shows particularly promising results in improving endurance. Numerous anecdotal reports speak of a significant increase in endurance and enhanced performance capacity even after a short period of use.

A study on Kunming mice specifically investigated this Cardarine-induced increase in endurance. The mice's running performance was analyzed over a period of three weeks [R]. The animals were divided into four groups:

1. Untrained and untreated control group (NN)
2. Untrained mice that received GW501516 (NG)
3. Trained but untreated mice (TN)
4. Trained mice that received GW501516 (TG)

Result: The study showed that Cardarine significantly increased running performance in both the untrained and trained groups. Particularly impressive was the performance increase in mice that received Cardarine and simultaneously trained: their running performance increased by a remarkable 68.6% in 3 weeks. [R]

But how exactly does Cardarine improve endurance?

Through the activation of PPARδ, Cardarine promotes fatty acid oxidation. The body now no longer uses glucose as its main energy source, but fatty acids. This switch increases energy efficiency in the muscles and thus improves endurance.

Cardarine and Cholesterol

Through the activation of the PPAR-δ receptor, Cardarine can also influence the lipid profile.
Studies report that Cardarine affects the lipid profile in the following ways [R]:

• Cardarine increases HDL (the good cholesterol)
• Cadarine reduces LDL (the bad cholesterol)
• Cardarine improves the LDL/HDL ratio: A better ratio between these two types of cholesterol can reduce the risk of cardiovascular diseases.

Can Cardarine cause Cancer?

In 2009, research findings were published that had led to the discontinuation of Cardarine research in 2007. A study showed that Cardarine could increase cancer risk in rats [R].

So does Cardarine also increase the risk of cancer in humans?   Maybe  -  it's hard to answer:

The study was conducted on Han Wistar rats. The rats were given Cardarine daily for 2 years. The rats were administered different doses, with the lowest dose that led to an increased cancer risk in rats being 3mg/kg/day [R].

2 years is a very long period, especially considering that a Han Wistar rat has an average life expectancy of 3 years [R]. It should also be mentioned that the most common natural cause of death in this rat species is already tumor diseases.

The dose administered in the study is also relatively high, considering that a Han Wistar rat weighs between 200 and 650g.
Converted to an 80kg human, a daily dose of 3mg equals approximately 45mg [R].

Whether Cardarine can also increase cancer risk in humans – even at lower doses and shorter intake periods – is still unclear. However, one should be aware of this potential risk. In a 12-week study where participants were given up to 10 mg of Cardarine daily, no increased cancer risk was found [R].

Is Cardarine legal?

Is Cardarine legal in Germany?

In Germany, Cardarine falls under the Anti-Doping Law. Therefore, sale and possession can lead to penalties.

The "non-small quantity" for Cardarine is 225mg [R].

Is Cardarine prohibited by the World Anti-Doping Agency (WADA)?

Yes, Cardarine was banned by the World Anti-Doping Agency (WADA) in 2009 [R]. Therefore, anyone who tests positive must expect disqualification or even suspension.

Cardarine Dosage

In clinical studies, Cardarine was mainly tested in doses between 2.5 mg and 10 mg per day. The study duration typically ranged between 2 and 12 weeks.

The History of Cardarine

Cardarine was discovered in 1992 through a partnership between GlaxoSmithKline (GSK) and Ligand Pharmaceuticals. From this point on, GSK conducted intensive research on Cardarine, leading to the initiation of the first Phase I tests in 2000. Originally, Cardarine was researched as a potential treatment for hyperlipoproteinemia – to lower elevated cholesterol levels. Therefore, further Phase I/II studies followed in 2002.

Research on Cardarine continued as it showed promising results in regulating fat metabolism and in the potential treatment of obesity, diabetes, dyslipidemia, and cardiovascular diseases.
In 2007, several clinical studies were completed, including two Phase II studies. Nevertheless, GSK discontinued research on Cardarine. The reason for this lay in animal experiments where the substance showed carcinogenic effects at high doses (3 mg per kg body weight in mice). [R]

Is Cardarine used by bodybuilders?

Yes, due to its numerous advantages for athletes and athletes, Cardarine continues to be frequently used. The World Anti-Doping Agency (WADA) developed a test to detect Cardarine already in 2009 and banned the substance in the same year.