Overview
Cardarine is commonly categorized alongside SARMs, though it is technically a PPARδ receptor agonist rather than a selective androgen receptor modulator. PPARδ receptor agonist — not a selective androgen receptor modulator despite common categorization.
With a half-life of ~16 hours, Cardarine requires daily administration in most observed protocols. Taken orally, it has a bioavailability of approximately 95% via its primary route.
Half-life approximately 16 hours. Non-suppressive to endogenous hormone production. High oral bioavailability. One-compartment model.
Mechanism of Action
Cardarine's pharmacological activity involves the following key pathways:
Selective Receptor Binding
Cardarine is designed to selectively bind to androgen receptors in muscle and bone tissue, with reduced activity in other androgen-sensitive tissues.
Tissue Selectivity
The selectivity of Cardarine is achieved through differential coactivator recruitment — the compound activates different downstream pathways depending on the tissue type.
Dosing Protocols
The following protocols represent commonly observed dosing patterns. These are observational summaries, not recommendations.
Dose
10 mg/day
Route
Oral
Frequency
Once daily
Duration
8-12 weeks
Dose
20 mg/day
Route
Oral
Frequency
Once daily
Duration
8-12 weeks
Frequently Asked Questions
What is Cardarine (GW-501516) and how does it work?
Cardarine (GW-501516) is a PPARdelta receptor agonist, not a selective androgen receptor modulator (SARM), though it is commonly grouped with SARMs in the performance community. Developed by Ligand Pharmaceuticals and GlaxoSmithKline in the 1990s, it activates PPARdelta receptors to upregulate genes involved in fatty acid oxidation and energy expenditure. This shifts the body's fuel preference from glucose toward stored fat.
Is Cardarine a SARM?
Cardarine is not a SARM. It is a PPARdelta (peroxisome proliferator-activated receptor delta) agonist that works through an entirely different pathway than SARMs. While SARMs bind to androgen receptors to produce anabolic effects, Cardarine activates metabolic receptors that regulate fat burning and energy output. It does not interact with androgen receptors, does not affect testosterone production, and does not require post-cycle therapy.
Does Cardarine suppress testosterone?
Cardarine does not suppress endogenous testosterone production because it does not interact with the androgen receptor or the hypothalamic-pituitary-gonadal axis. This is a key distinction from actual SARMs and anabolic compounds. Post-cycle therapy is not typically observed following Cardarine-only cycles. This non-hormonal profile is one reason it is frequently stacked with suppressive SARMs – it adds performance benefits without compounding hormonal suppression.
What is the half-life of Cardarine (GW-501516)?
Cardarine has a half-life of approximately 16–24 hours, allowing for convenient once-daily dosing. Some users who opt for higher doses report splitting the dose into two administrations approximately 10–12 hours apart. The long half-life means stable plasma levels are reached relatively quickly, and timing is flexible throughout the day.
How does Cardarine improve endurance?
PPARdelta activation by Cardarine reprograms muscle fiber metabolism to preferentially oxidize fatty acids for energy instead of glucose. Preclinical research demonstrated that GW-501516 combined with exercise training increased running time by 68% and running distance by 70% in animal models. These effects on aerobic capacity and stamina are the most consistently reported benefits in the performance community.
How long is a typical Cardarine cycle?
Cardarine cycles are most commonly observed in the 8–12 week range, followed by a 4–week break. When stacked with SARMs, shorter 6–8 week durations are frequently reported to align with the SARM cycle length. Because Cardarine is non-hormonal and non-suppressive, cycle duration is generally limited by receptor sensitivity considerations rather than hormonal recovery needs.