Cardarine (GW501516): Dosage, Cycle, Benefits, and Side Effects

What is cardarine?

Cardarine, or GW501516, is a peroxisome proliferator-activated receptor delta (PPARD) agonist. However, due to its similar anabolic and fat-burning effects, people sometimes incorrectly refer to it as a SARM.

Cardarine was formulated in 1992 and is classified as a research compound. It remains unapproved by the FDA due to significant safety concerns, highlighting the risks associated with its use in humans.

Early research has demonstrated cardarine’s positive effects on body composition and athletic performance, causing it to be banned in sports. The World Anti-Doping Agency (WADA) has added cardarine to its list of prohibited substances, placing it in the category of hormones and metabolic modulators.

Cardarine’s potent fat-burning effects could provide promise for treating obesity in a controlled research setting; however, due to substantial safety concerns and lack of FDA approval, its use in uncontrolled environments poses significant health risks.

While some weightlifters report using cardarine to retain muscle mass and enhance fat loss during cutting cycles, this practice is not recommended due to the significant health risks, including potential long-term carcinogenic effects.

What is the legal status of cardarine?

The FDA has yet to approve cardarine due to safety concerns. Thus, it is illegal for users to purchase cardarine in an attempt to improve their body composition.

However, it is legal to purchase cardarine for research purposes. Such an instance could involve administering it to a group of rodents and observing its effects.

What are the benefits of cardarine?

1. Fat Loss
2. Muscle hypertrophy
3. Muscle endurance
4. Glycogen storage
5. Improved cholesterol
6. Testosterone suppression
7. No virilization in women

1. Fat loss

Cardarine enhances lipolysis by improving:

• Insulin sensitivity
• Lipid balance
• Glucose tolerance

Cardarine stimulates fatty acid oxidation by reducing the utilization of glucose, thus shifting energy metabolism. Consequently, the body uses fat stores as a primary energy source.

This causes a decrease in both subcutaneous and visceral fat mass in users, producing a leaner and more defined appearance. Decreases in visceral fat enable individuals to maintain a small waist, with high levels causing a protruding look to the stomach.

Dr. Anthony Hughes has cycled cardarine for over 15 years and describes it as a “miracle compound,” claiming it increased his caloric burn by 30% per hour. However, it is important to recognize that individual responses to cardarine can vary significantly, and not everyone may experience the same benefits.

Cardarine’s lipolytic effects are similar to SARMs used for cutting, such as ostarine. Anecdotally, we have found that cardarine’s fat-burning properties surpass its ability to build lean muscle tissue.

2. Muscle hypertrophy

There is evidence of cardarine having mild anabolic effects, with a phase 2 study observing a 1.3 kg lean mass increase in users (1), following a dosage of 10 mg/day for 12 weeks. This modest increase in muscularity is similar to SARMs, although with less potency.

3. Muscle endurance

We have seen cardarine positively affect muscular endurance due to the remodeling of muscle tissue via mitochondrial biogenesis. Research indicates that cardarine facilitates the conversion of fast-twitch muscle fibers into slow-twitch fibers (2), thereby reducing a user’s susceptibility to fatigue during exercise.

Slow-twitch fibers are more efficient at utilizing oxygen due to the presence of mitochondria, enabling increased levels of adenosine triphosphate (ATP) production inside the muscle cells. A study on mice found cardarine to increase endurance by 68% in just 3 weeks (3).

To translate these results in human terms, if a person usually engages in 30 minutes of cardio activity before tiring, they may sustain 50 minutes before reaching the same degree of fatigue on cardarine. However, each individual’s results may vary.

Cardarine’s effects on muscular endurance are potent. Increased endurance may indirectly aid fat burning when combined with regular cardiovascular training due to increased calorie burn.

In our experience, users have reported cardarine’s endurance-boosting results diminishing following cycle cessation. More research is needed to understand the extent and duration of its effects on physical performance. The level of endurance retained from a cardarine cycle may depend on whether the user continues cardiovascular training post-cycle.

4. Glycogen storage

Cardarine increases intracellular glycogen storage; thus, users can experience fuller muscles on-cycle.

Increases in vascularity may also occur on cardarine due to decreased levels of extracellular fluid.

5. Improved cholesterol

• Based on our lipid profile tests, cardarine has cardioprotective properties, significantly increasing HDL cholesterol. This is a unique trait compared to SARMs and anabolic steroids, which can cause negative cholesterol fluctuations.
• In the previous phase 2-cited study, HDL levels increased by 17% and LDL cholesterol decreased by 7% from a 10 mg/day dosage.

6. No testosterone suppression

Anabolic steroids and SARMs decrease endogenous testosterone levels, which is caused by overstimulation of the androgen receptor. However, PPARD agonists do not affect the hypothalamic-pituitary-testicular axis (HPTA); thus, testosterone levels will remain stable on cardarine with no post-cycle therapy (PCT) required.

7. No virilization in women

Cardarine does not cause masculinization in women. This is due to cardarine not affecting testosterone and thus preventing:

1. Hair loss
2. Clitoral enlargement
3. Breast reduction
4. Deeper voice

Although cardarine does not cause masculinization effects in women, users should remain aware of the significant health risks involved, including potential liver toxicity and an increased risk of cancer.

What are the side effects of cardarine?

1. Potential cancer
2. Liver toxicity
3. Insomnia

1. Potential cancer

In 2009, cardarine was withdrawn from further development after it produced cancer in all tested dosages, following long-term preclinical safety trials (4). Such tests are standard for safety evaluations, with approved medications passing such requirements.

Tumors were found in the following:

1. Thyroid
2. Liver
3. Bladder
4. Stomach
5. Skin
6. Tongue
7. Uterus
8. Eyes
9. Testes

Such trials have been criticized by some individuals in the fitness community due to excessive dosages and the duration of use. The lowest dosage given to rodents was 5 mg/kg per day, which translates to 500 mg/day for a 100 kg human.

A 2-year cardarine cycle, as conducted in the research, is extensive compared to weightlifters’ cycles, with the latter typically administering it for 8 weeks.

Dr. Rand McClain expresses skepticism about the carcinogenic effects of cardarine based on extreme dosages tested in rodent studies. However, it is important to note that the majority of research points to significant safety risks associated with its use, necessitating caution.

Therefore, it is unclear how carcinogenic cardarine is until it undergoes human trials with moderate doses over standard periods.

2. Liver toxicity

In phase 1 and 2 human studies, cardarine demonstrated fluctuations in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) liver enzymes at dosages up to 10 mg/day. Therefore, monitoring liver function is crucial, as elevated enzyme levels could indicate potential liver damage.

Dr. Thomas O’Connor has treated patients who have used cardarine and consequently has likened its hepatotoxicity to the equivalent of taking “50 mg/day of Anavar.”

The reason for conflicting hepatic results in research and anecdotal data may be attributed to cardarine causing cellular proliferation. By stimulating cell growth and division, cardarine increases overall cell count. This is an acceptable chemical process in a healthy person, but in the case of someone with an existing hepatic injury, cardarine may accelerate hepatic necrosis (5).

We find that cardarine is often taken by individuals who have also used SARMs or anabolic steroids; however, this combination can exacerbate potential hepatic complications, increasing ALT and AST enzymes.

Note: Antidepressants and alcohol consumption may also be disadvantageous combinations in conjunction with cardarine. Thus, users should monitor their liver enzymes to be aware of the condition of their liver before any potential cellular proliferation occurs.

3. Insomnia

Some cardarine users report insomnia, indicating a potential stimulating effect on the central nervous system (CNS) and an increase in adrenaline output.

In our experience, cardarine does not replicate the jittery effects of thermogenic fat burners, such as clenbuterol. Instead, we find that energy levels on cardarine remain stable while maintaining overall well-being in users.

Cardarine dosage

Due to cardarine not being approved by the FDA for medicinal purposes, there are no established dosage guidelines. Users should be cautious, as intakes commonly range from 10–20 mg/day (6) among bodybuilders, but consulting a healthcare professional is essential for safety. In clinical studies, researchers have administered up to 10 mg/day to participants.

Cardarine is typically taken once per day and approximately 30 minutes before workouts to enhance fat oxidation during exercise.

Cardarine cycle

Cardarine is not intended for human consumption. The following cardarine cycle is a common protocol that we have seen administered by male and female patients seeking improvements in muscular endurance and fat loss.

• Week 1: 20 mg/day
• Week 2: 20 mg/day
• Week 3: 20 mg/day
• Week 4: 20 mg/day
• Week 5: 20 mg/day
• Week 6: 20 mg/day
• Week 7: 20 mg/day
• Week 8: 20 mg/day

The above cycle consists of moderate dosages. Experienced users may administer 30 mg/day with cycles extending to 12 weeks.

However, dosages above 20 mg/day produce minimal additional results in our experience. Furthermore, we have observed beneficial effects on conservative dosages of 10 mg/day when taken for 4–6 weeks.

Can cardarine be stacked with other compounds?

Due to cardarine’s cellular proliferation ability, it may not be disadvantageous to stack it with hepatotoxic compounds, such as SARMs or oral anabolic steroids. Doing so may exacerbate their adverse effects on the liver, further increasing ALT and AST enzymes and the risk of cholestatic hepatitis.

How do users take cardarine?

• Like SARMs, cardarine typically comes as a liquid solution (20 mg/mL) or in tablet form (10 mg).
• Researchers sometimes use a syringe to measure liquid cardarine before placing it in the mouth to swallow.

We have found that taking cardarine sublingually notably increases absorption (7) by letting it sit underneath the tongue for 10–15 seconds before swallowing. This method allows it to contact the mucous membrane, allowing a more direct route into the bloodstream and thus greater biological availability.

What is the half-life of cardarine?

The half-life of cardarine, or GW501516, is approximately 12–24 hours.

Can cardarine be taken on an empty stomach?

Cardarine’s biological availability remains unchanged when consumed on an empty stomach.

Cardarine reviews: What are researchers reporting?

The following cardarine reviews were posted in our Facebook group and have been republished below.

I lost 40 pounds after a 3-month cycle of cardarine. I was losing 3 to 4 pounds per week! You want to be eating clean during supplementation. Also, do cardio. You’ll cut weight like you’ve never seen. I didn’t notice any adverse effects. If muscle mass is important to you, stack it alongside ostarine. Amazing compound.

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My extremely limited experience with cardarine is pretty amazing. Jumped on the bike and rode hard for 60 minutes. I felt better in the last 15 minutes than I did in the first 15 minutes. The weirdest thing is I’m not even breathing hard during the whole session. This is a 10 mL dose.

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The endurance from GW is crazy; however, it gives no buzz, so to speak, or crash. It works straight away after the 1st dose, but I’ve found the effects wear off over time, so you have to increase the dosage; however, I’ve never gone over 30 mg per day.

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I was massively suppressed on ostarine and cardarine. I think I went too low on my calories to boot. Looking forward to redoing bloodwork in a week or two.

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Summary: Does cardarine offer therapeutic value?

Cardarine, or GW501516, is a potent fat-burning compound. However, its effects on muscular strength and hypertrophy are minimal in our experience.

Cardarine’s ability to enhance muscular endurance may be notable (8); however, it is accompanied by serious long-term health risks, including evidence of carcinogenicity in rodent studies, which significantly overshadows potential benefits.

Additionally, it is a prohibited substance by the World Anti-Doping Agency (WADA); therefore, Olympic athletes supplementing with cardarine are at risk of failing a drug test.

The main reason weightlifters purchase cardarine is to burn fat and improve their body composition. However, these two objectives can be achieved naturally with a diligent exercise and diet plan.

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