Non-peptide

Cardarine

Also known as

GW501516 · GW-501516 · GW 501516 · GW1516 · GW-1516 · GW 1516 · GW-501,516 · GSK-516 · Endurobol · Cardarine (Endurobol)

Community talk. May contain inaccuracies. Not medical advice. Not a protocol. Not for human or animal use.

What it is

Experimental endurance compound	Cardarine, or GW501516, activates PPARδ, a receptor involved in fuel use. People discuss it for easier cardio during a cut; it is not a SARM or peptide.
Oral research products	The logs describe capsules and liquids. Cardarine remains unapproved, and labeled amounts do not verify a product's identity or strength.

Notes

Cardarine (GW501516) is an experimental oral compound discussed for making cardio feel easier and supporting endurance during a cut. It is not a SARM. Accounts range from noticeable stamina to no change, and the animal tumor findings remain a major unresolved safety concern.

A metabolic compound, rather than an androgen drug. Also called Endurobol or GW1516, GW501516 activates PPARδ, a receptor involved in fuel use. The endurance idea concerns energy metabolism rather than direct muscle building. Cardarine is a small molecule, not a peptide or an androgen-receptor drug; a SARM-shop label does not change that identity. What Should Tested Athletes Know About GW1516? (Official context · Accessed 2026-09-30)

Oral capsules and liquids appear in the logs. The inspected accounts describe capsules and an oral liquid. Older notes also mention tablets and research powder; injection is not the usual route described here. Labeled milligrams cannot establish the identity or strength of an unverified product. Cardarine Journey (Personal report · Accessed 2026-09-30) · Cardarine AKA GW-501516/50156, a review of day 1 (Personal report · Accessed 2026-09-30)

It remains unapproved. There is no approved medicine for these endurance or cutting uses. Short human lipid studies do exist, but they do not establish long-term safety or athletic effectiveness. WADA issues alert on GW501516 (Official context · Accessed 2026-09-30) · Olson et al.: lipid effects in subjects with low HDL cholesterol (Official context · Accessed 2026-09-30)

Source context — What Should Tested Athletes Know About GW1516?: Educational summary uses an older S4.5 numbering and erroneously says no human studies. Those parts are not repeated; current list and primary human abstracts supply the correction.

Source context — Cardarine Journey: Anonymous, unverified oral liquid; changing training and no control. Opening cycle date says 2024 but updates say 2025; report dates retained, not silently reconciled.

Source context — Cardarine AKA GW-501516/50156, a review of day 1: Only page 1 inspected. Author wrongly calls Cardarine a SARM; corrected using official identity context. Planned trenbolone and pre-workout/caffeine confound experiences; no efficacy or interaction inferred.

Source context — WADA issues alert on GW501516: Historical alert, not a numeric human risk estimate or modern clinical study.

Source context — Olson et al.: lipid effects in subjects with low HDL cholesterol: Primary abstract only, no full-text inspection. Not a repeated-cycle cancer study or a performance trial; retrieved abstract does not supply verified human clearance.

What people notice

Cardio feels easier	Some describe longer runs or less effort during conditioning, often without a stimulant-like feeling at rest. That does not demonstrate automatic fat loss.
No added endurance	One trained runner reported no change in endurance, sprint recovery or heart-rate readings. Claims that the bottle was fake remained unproven.
After stopping	One author reported retained cardio gains two weeks later; another reply described much harder cardio. Training changes prevent separating fitness gains from drug effects.

Notes

Longer cardio with less perceived effort. A six-week runner described being able to continue farther late in a run without the dramatic transformation promised by other posts. Incline walking, running, basketball and conditioning are recurring contexts; a quieter resting sensation does not tell the whole performance story. 6 week Cardarine report: not a third pair of lungs or fat shredder (Personal report · Accessed 2026-09-30)

Help staying active during a calorie deficit. Users discuss easier training and more cardio volume during cuts. That does not demonstrate automatic fat loss or muscle gain: diet, weight loss and training changes occur alongside use. Lipid-panel interest is a separate goal, not proof that endurance improved. 6 week Cardarine report: not a third pair of lungs or fat shredder (Personal report · Accessed 2026-09-30) · 8.5 week 15mg cycle AMA (Personal report · Accessed 2026-09-30)

Feeling little at rest can coexist with easier training. Some logs describe less fatigue without a stimulant-like buzz. The first-workout author reported no obvious sensation until cardio; the CrossFit log shows that unwanted activation can still occur. A “clean feel” is not evidence of safety. Does Cardarine actually do that much? Will Post Results (Personal report · Accessed 2026-09-30) · 8.5 week 15mg cycle AMA (Personal report · Accessed 2026-09-30) · Amazing cardio benefits but feeling overstimulated (Personal report · Accessed 2026-09-30)

Nonresponse is not automatically a fake bottle. The trained runner's endurance, sprint recovery and heart-rate readings remained unchanged; small gains were attributed to the training plan. Replies proposed product quality or training background, but neither explanation was established. Cardarine Journey (Personal report · Accessed 2026-09-30)

After stopping, reports disagree. The 8.5-week log described retained cardio gains two weeks off. In the six-week thread, the author felt unchanged after two runs off, while a reply described much harder cardio after stopping. Older notes also mention lower energy after a six-week course. Training gains and drug-related effects cannot be separated here. 8.5 week 15mg cycle AMA (Personal report · Accessed 2026-09-30) · 6 week Cardarine report: not a third pair of lungs or fat shredder (Personal report · Accessed 2026-09-30)

Keeping gains after stopping does not prove lingering drug action. The 8.5-week author trained three times a day and also cut caffeine substantially. Better fitness could persist after stopping even if the compound no longer contributes; the same author could not separate effort, expectancy and Cardarine. 8.5 week 15mg cycle AMA (Personal report · Accessed 2026-09-30)

Source context — 6 week Cardarine report: not a third pair of lungs or fat shredder: Anonymous/unverified product; first two weeks included Ostarine and dieting/running changed. Testosterone suppression and attribution self-reported; exact publication date not inferred.

Source context — 8.5 week 15mg cycle AMA: Three daily run sessions, pace increases and large caffeine reduction confound attribution. User expressly cannot separate placebo/effort/drug; no exact publication date inferred from relative label.

Source context — Does Cardarine actually do that much? Will Post Results: Diet deficit and training change; no identity assay. Repeated 24-hour accumulation arithmetic is speculation. Vendor recommendations in the body not reproduced.

Source context — Amazing cardio benefits but feeling overstimulated: Anonymous product; CrossFit frequency increased from five to seven days; cannot establish causality. Planned 2.5/5 mg restart not presented as a completed outcome.

Doses people talk about

Oral: 10–20 mg/day	Reports include 10 mg each morning, 15 mg/day liquid and 20 mg/day taken together or as two 10 mg capsules. These are reported totals, not a recommended amount.
Lower amounts and another route	Older notes include 5–10 mg oral daily and an unlinked claim of about 3 mg sublingual. Anxiety occurred in an account using 2.5 mg then 5 mg on consecutive days.

Notes

Oral: 10–20 mg total daily in the existing discussion record. Inspected examples include 10 mg each morning, 15 mg daily oral liquid, and 20 mg daily as either one morning dose or two 10 mg capsules split morning/night. These are reports, not a recommended amount; no inspected account verifies bottle contents. Amazing cardio benefits but feeling overstimulated (Personal report · Accessed 2026-09-30) · Cardarine Journey (Personal report · Accessed 2026-09-30) · GW-501516 (Cardarine) dosing (Community discussion · Accessed 2026-09-30)

Lower amounts and different routes remain separate claims. Older notes include 5–10 mg oral daily and a separate claim of about 3 mg sublingual, without a linked measurement. An anxiety thread includes adverse experiences after 2.5 mg then 5 mg on consecutive days. Low amounts do not establish safety or equivalent absorption between routes. Anxiety on Cardarine? (Personal report · Accessed 2026-09-30)

Source context — GW-501516 (Cardarine) dosing: Thread includes unsupported 100 mg speculation, trial misstatements and a false linear claim that 20-fold dose means 20-fold faster onset. Those are rejected; only reports and attributed lore retained.

Source context — Anxiety on Cardarine?: Products unverified; pre-existing anxiety, stacked S-4 and alternative explanations appear. Comments denying anxiety or claiming a rate/mechanism are not evidence.

Half-life, onset & duration

Felt onset	One log describes easier cardio in the first workout; another places the change around day seven.
Felt duration	No reliable hours-per-dose benefit window is established. Reports mainly follow repeated daily use and changing workouts.
Half-life	12–24 hours and 24 hours circulate in forums, with conflicting 12-hour claims. The cited discussions provide no measured human clearance study.

Notes

First workout in one log; around day 7 in another; no change after about two weeks. A 15 mg capsule log claimed easier cardio immediately. A CrossFit user noticed endurance around day 7 at 10 mg/day. A runner reporting 15 mg daily still found no benefit in the February 25 update. Those differing experiences do not define a dependable onset. Does Cardarine actually do that much? Will Post Results (Personal report · Accessed 2026-09-30) · Amazing cardio benefits but feeling overstimulated (Personal report · Accessed 2026-09-30) · Cardarine Journey (Personal report · Accessed 2026-09-30)

No dependable single-dose benefit window. The logs mainly follow repeated daily use and changing workouts. A claimed 12- or 24-hour half-life cannot establish how many hours endurance feels different. Can I miss a day of it? (Secondhand community claim · Accessed 2026-09-30) · Cardarine Journey (Personal report · Accessed 2026-09-30) · 8.5 week 15mg cycle AMA (Personal report · Accessed 2026-09-30)

12–24 hours is circulated lore; 24 hours is another repeated estimate. AnabolicMinds repeats 12–24 hours, while a Reddit timing thread uses 24 hours and also contains a conflicting 12-hour claim. Neither supplies a measured human pharmacokinetic study. Half-life describes a measured amount falling by half, not the length of a cardio benefit. GW-501516 (Cardarine) dosing (Community discussion · Accessed 2026-09-30) · Can I miss a day of it? (Secondhand community claim · Accessed 2026-09-30)

Source context — Can I miss a day of it?: No human PK source. Vendor-style commenter 'sarmful' says use before cardio is fine; this assurance is excluded. The numeric disagreement is preserved without endorsing either.

Cycles people discuss

Six to eight weeks in charts	Opened accounts include six and 8.5 weeks; older notes also contain four-week probes and 8–12-week blocks. No length is established as safe.
Breaks vary	Discussion ranges from 3–4 weeks off to equal time off and on. Claims that breaks prevent tolerance or resolve tumor risk remain unproven.

Notes

6–8 weeks in older charts; shorter and longer blocks also appear. The existing record includes four-week probes and 8–12-week runs. Opened examples include a completed six-week run and an 8.5-week run, while a race-prep thread discusses extending beyond eight weeks. No length is established as safe. 6 week Cardarine report: not a third pair of lungs or fat shredder (Personal report · Accessed 2026-09-30) · 8.5 week 15mg cycle AMA (Personal report · Accessed 2026-09-30) · Cycling on and off (Community discussion · Accessed 2026-09-30)

Breaks range from 3–4 weeks to equal time off. The race thread contains 3–4 weeks off, six weeks off after twelve on, and 1–2 months off. Equal on/off time appears in older notes. Claims that breaks prevent tolerance or resolve tumor risk remain unproven; repeated seasonal use and continuous low-dose use lack a validated safety rule. Cycling on and off (Community discussion · Accessed 2026-09-30)

Source context — Cycling on and off: Anonymous dose/frequency details incomplete; advice is not validated risk management. No safe maximum or desensitization mechanism inferred.

Stacks

Cutting combinations	Ostarine, SR9009, S-4, LGD-4033 and MK-677 appear in older stacks. Stimulants and trenbolone also appear; their effects and risks cannot be assigned to Cardarine alone.
Recovery and lipid claims	Forum PCT discussions follow the suppressive drugs in the stack. Lipid tracking or adding L-carnitine for a claimed fade does not settle Cardarine's long-term risks.

Notes

Cutting stacks make both benefits and problems harder to assign. Older discussion pairs Cardarine with Ostarine, SR9009, S-4, LGD-4033 or MK-677, and sometimes stimulants or trenbolone to offset poor cardio. A six-week user stopped Ostarine after reported testosterone problems. Forum talk treats solo Cardarine as not requiring post-cycle therapy (PCT); that does not cancel a stack's suppression or other risks. 6 week Cardarine report: not a third pair of lungs or fat shredder (Personal report · Accessed 2026-09-30) · Cardarine AKA GW-501516/50156, a review of day 1 (Personal report · Accessed 2026-09-30)

Cancer arguments and lab tracking do not settle safety. Some posts dismiss the rodent findings as excessive-dose experiments; others reject that reassurance. Older notes include cancer anxiety, lipid/liver-enzyme tracking and L-carnitine added for a claimed weeks-4–6 fade. Neither reassuring labs nor the proposed carnitine-depletion explanation resolves long-term risk.

Watch for

Animal tumor findings	The 104-week rat and mouse studies found treatment-related tumors at every tested dose. They do not establish a human cancer rate or a safe forum amount.
Anxiety and poor sleep	Accounts include nervousness, panic-like symptoms, brain fog and insomnia. Product quality, prior anxiety and other drugs remain unresolved in some reports.
Tested sport	Cardarine is prohibited at all times. Forum half-life arithmetic cannot establish a drug-test clearance window, and normal bloodwork cannot clear the tumor concern.

Notes

The tumor concern comes from animal studies. The 104-week rat and mouse abstracts found treatment-related tumors at every tested dose. They do not measure a human cancer rate or establish a safe forum amount. WADA attributes development's termination to serious preclinical toxicities. Geiger and Newsholme: rat and mouse carcinogenicity studies with GW501516 (Animal context · Accessed 2026-09-30) · WADA issues alert on GW501516 (Official context · Accessed 2026-09-30)

Anxiety, brain fog and insomnia appear in accounts. A CrossFit user reported nervousness by days 7–9 and poor sleep; another thread describes panic-like symptoms after two days, with product quality and pre-existing anxiety unresolved. Older notes also contain headache, stomach upset, fatigue, dizziness and enzyme changes, often with stacks. Amazing cardio benefits but feeling overstimulated (Personal report · Accessed 2026-09-30) · Anxiety on Cardarine? (Personal report · Accessed 2026-09-30)

Prohibited in tested sport at all times. WADA lists GW1516/GW501516 under metabolic modulators. Forum half-life arithmetic is not a drug-test clearance window; normal bloodwork also cannot clear the tumor concern. The Prohibited List (Official context · Accessed 2026-09-30)

Source context — Geiger and Newsholme: rat and mouse carcinogenicity studies with GW501516: Conference abstracts only, not full study reports. Animal tumors cannot quantify human cancer probability or yield a safe amount. Lowest female-rat 3 mg/kg/day must not be assigned to both species.

Source context — WADA issues alert on GW501516: Historical alert, not a numeric human risk estimate or modern clinical study.

Source context — The Prohibited List: Live list checked on access date; not a human clearance/detection-window source. No private athlete testing advice inferred.

Full notes

What Cardarine is

A metabolic compound, rather than an androgen drug. Also called Endurobol or GW1516, GW501516 activates PPARδ, a receptor involved in fuel use. The endurance idea concerns energy metabolism rather than direct muscle building. Cardarine is a small molecule, not a peptide or an androgen-receptor drug; a SARM-shop label does not change that identity. Official context
Oral capsules and liquids appear in the logs. The inspected accounts describe capsules and an oral liquid. Older notes also mention tablets and research powder; injection is not the usual route described here. Labeled milligrams cannot establish the identity or strength of an unverified product. Personal report Personal report Community
It remains unapproved. There is no approved medicine for these endurance or cutting uses. Short human lipid studies do exist, but they do not establish long-term safety or athletic effectiveness. Official context Official context

Benefits people seek

Longer cardio with less perceived effort. A six-week runner described being able to continue farther late in a run without the dramatic transformation promised by other posts. Incline walking, running, basketball and conditioning are recurring contexts; a quieter resting sensation does not tell the whole performance story. Personal report Community
Help staying active during a calorie deficit. Users discuss easier training and more cardio volume during cuts. That does not demonstrate automatic fat loss or muscle gain: diet, weight loss and training changes occur alongside use. Lipid-panel interest is a separate goal, not proof that endurance improved. Personal report Personal report Community

Doses people discuss

Reported milligrams describe what users say they took, not a validated regimen.

Oral: 10–20 mg total daily in the existing discussion record. Inspected examples include 10 mg each morning, 15 mg daily oral liquid, and 20 mg daily as either one morning dose or two 10 mg capsules split morning/night. These are reports, not a recommended amount; no inspected account verifies bottle contents. Personal report Personal report AnabolicMinds Community
Lower amounts and different routes remain separate claims. Older notes include 5–10 mg oral daily and a separate claim of about 3 mg sublingual, without a linked measurement. An anxiety thread includes adverse experiences after 2.5 mg then 5 mg on consecutive days. Low amounts do not establish safety or equivalent absorption between routes. Community Personal report

Half-life

12–24 hours is circulated lore; 24 hours is another repeated estimate. AnabolicMinds repeats 12–24 hours, while a Reddit timing thread uses 24 hours and also contains a conflicting 12-hour claim. Neither supplies a measured human pharmacokinetic study. Half-life describes a measured amount falling by half, not the length of a cardio benefit. AnabolicMinds Reddit · r/cardarine Community

Onset: when people notice a change

First workout in one log; around day 7 in another; no change after about two weeks. A 15 mg capsule log claimed easier cardio immediately. A CrossFit user noticed endurance around day 7 at 10 mg/day. A runner reporting 15 mg daily still found no benefit in the February 25 update. Those differing experiences do not define a dependable onset. Personal report Personal report Personal report
Before-cardio timing is a habit, not measured onset. Posts describe use 15 minutes, 30–45 minutes or an hour before exercise; others use a fixed morning time. Older notes disagree about food timing. These preferences do not establish a superior timing or food rule. Personal report Reddit · r/cardarine Personal report Community

Duration: how long effects last

No dependable single-dose benefit window. The logs mainly follow repeated daily use and changing workouts. A claimed 12- or 24-hour half-life cannot establish how many hours endurance feels different. Reddit · r/cardarine Personal report Personal report
After stopping, reports disagree. The 8.5-week log described retained cardio gains two weeks off. In the six-week thread, the author felt unchanged after two runs off, while a reply described much harder cardio after stopping. Older notes also mention lower energy after a six-week course. Training gains and drug-related effects cannot be separated here. Personal report Personal report Community

Cycles and time off

6–8 weeks in older charts; shorter and longer blocks also appear. The existing record includes four-week probes and 8–12-week runs. Opened examples include a completed six-week run and an 8.5-week run, while a race-prep thread discusses extending beyond eight weeks. No length is established as safe. Community Personal report Personal report Reddit · r/cardarine
Breaks range from 3–4 weeks to equal time off. The race thread contains 3–4 weeks off, six weeks off after twelve on, and 1–2 months off. Equal on/off time appears in older notes. Claims that breaks prevent tolerance or resolve tumor risk remain unproven; repeated seasonal use and continuous low-dose use lack a validated safety rule. Reddit · r/cardarine Community

Good to know

The tumor concern comes from animal studies. The 104-week rat and mouse abstracts found treatment-related tumors at every tested dose. They do not measure a human cancer rate or establish a safe forum amount. WADA attributes development's termination to serious preclinical toxicities. Animal context Official context
Anxiety, brain fog and insomnia appear in accounts. A CrossFit user reported nervousness by days 7–9 and poor sleep; another thread describes panic-like symptoms after two days, with product quality and pre-existing anxiety unresolved. Older notes also contain headache, stomach upset, fatigue, dizziness and enzyme changes, often with stacks. Personal report Personal report Community
Prohibited in tested sport at all times. WADA lists GW1516/GW501516 under metabolic modulators. Forum half-life arithmetic is not a drug-test clearance window; normal bloodwork also cannot clear the tumor concern. Official context Community

From community discussion

Feeling little at rest can coexist with easier training. Some logs describe less fatigue without a stimulant-like buzz. The first-workout author reported no obvious sensation until cardio; the CrossFit log shows that unwanted activation can still occur. A “clean feel” is not evidence of safety. Personal report Personal report Personal report
Nonresponse is not automatically a fake bottle. The trained runner's endurance, sprint recovery and heart-rate readings remained unchanged; small gains were attributed to the training plan. Replies proposed product quality or training background, but neither explanation was established. Personal report
Keeping gains after stopping does not prove lingering drug action. The 8.5-week author trained three times a day and also cut caffeine substantially. Better fitness could persist after stopping even if the compound no longer contributes; the same author could not separate effort, expectancy and Cardarine. Personal report
Cutting stacks make both benefits and problems harder to assign. Older discussion pairs Cardarine with Ostarine, SR9009, S-4, LGD-4033 or MK-677, and sometimes stimulants or trenbolone to offset poor cardio. A six-week user stopped Ostarine after reported testosterone problems. Forum talk treats solo Cardarine as not requiring post-cycle therapy (PCT); that does not cancel a stack's suppression or other risks. Community Personal report Personal report
Cancer arguments and lab tracking do not settle safety. Some posts dismiss the rodent findings as excessive-dose experiments; others reject that reassurance. Older notes include cancer anxiety, lipid/liver-enzyme tracking and L-carnitine added for a claimed weeks-4–6 fade. Neither reassuring labs nor the proposed carnitine-depletion explanation resolves long-term risk. Community Community Community
Other compounds bring different practical problems. Older comparisons contrast SR9009's several-times-daily lore with once-daily Cardarine, note S-4 vision complaints and MK-677 hunger/water retention, and compare SLU-PP-332/915's different receptor and route debates. These are separate compounds, without a verified head-to-head ranking. Community Community

Human metabolic studies and animal tumor findings

Human lipid trials used different amounts and endpoints. Sprecher's small study used 2.5 or 10 mg orally once daily for two weeks. Olson's 268-patient study tested 2.5, 5 or 10 mg over twelve weeks and found lipid changes. These were not demonstrations of athletic performance, repeated-cycle safety or a way to neutralize SARM damage. Official context Official context
Animal study amounts differ by species and sex. Lowest daily oral-gavage amounts were 3 mg/kg in female rats, 5 in male rats and 10 in mice, over 104 weeks. These animal exposures do not define a safe human threshold. Animal context