RAD-140 (Testolone) vs SR-9009 (Stenabolic)

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

RAD-140 (Testolone)SR-9009 (Stenabolic)
CategorySARMsSARMs
Standard DoseResearch indicates 10-20 mg daily orally for 8-12 weeks. Phase 1 clinical trial (oncology) identified 100 mg as the maximum tolerated dose.Research indicates 20-30 mg daily orally, split into 3-4 doses due to very short half-life (~4 hours). Some users prefer sublingual administration for improved bioavailability.
TimingOnce daily, consistent timing. Very long half-life (~60 hours) means stable plasma levels even with once-daily dosing. Morning preferred.Split into 3-4 doses throughout the day due to ~4-hour half-life. Example: 7am, 11am, 3pm, 7pm. Avoid late-night dosing as REV-ERB modulation may affect circadian rhythm and sleep.
Cycle Duration8-12 week cycles. PCT mandatory due to significant HPG axis suppression.8-12 week cycles. No HPG suppression. Cycling recommended due to limited long-term data.
Evidence Levelanimal_plus_anecdotalanimal_plus_anecdotal

Mechanism

RAD-140 is a potent nonsteroidal SARM with high oral bioavailability and selectivity for muscle and bone AR over prostate. It acts as a full agonist at the AR in muscle tissue, promoting nitrogen retention and protein synthesis via mTOR/p70S6K pathway activation. RAD-140 also demonstrates neuroprotective properties, acting against beta-amyloid-induced neurotoxicity through AR-mediated MAPK/ERK signaling. Preclinical data show greater anabolic potency than testosterone propionate at equivalent doses with significantly reduced prostate stimulation.

Standard Dosing

Research indicates 10-20 mg daily orally for 8-12 weeks. Phase 1 clinical trial (oncology) identified 100 mg as the maximum tolerated dose.

Timing

Once daily, consistent timing. Very long half-life (~60 hours) means stable plasma levels even with once-daily dosing. Morning preferred.

Cycle Duration

8-12 week cycles. PCT mandatory due to significant HPG axis suppression.

Side Effects

  • Significant testosterone suppression
  • Hepatotoxicity (multiple published case reports of drug-induced liver injury)
  • HDL suppression and LDL elevation
  • Aggression and mood changes
  • Hair shedding (androgenic effect despite 'selective' designation)
  • Insomnia
  • Headache

Contraindications

  • Pre-existing liver disease
  • Androgen-sensitive cancers
  • Cardiovascular disease (LDL elevation concern)
  • Pregnancy and breastfeeding
  • Individuals under 21
  • Athletes subject to anti-doping testing

Best Stacking Partners

MK-677 (GH secretagogue for enhanced recovery and countering suppression symptoms)Cardarine GW-501516 (endurance)NAC / TUDCA (liver protection — essential)

Mechanism

SR-9009 is a synthetic agonist of REV-ERBa and REV-ERBb, nuclear receptors that form the repressive limb of the circadian clock and regulate metabolic gene expression. REV-ERB activation represses BMAL1/CLOCK transcription, modulating circadian rhythm. In skeletal muscle, SR-9009 increases mitochondrial count and oxidative capacity by upregulating mitochondrial biogenesis genes. It enhances fatty acid and glucose oxidation, increases exercise endurance, and reduces lipogenesis in the liver. SR-9009 also reduces inflammatory gene expression via NF-kB pathway suppression. Recent research has identified significant REV-ERB-independent effects, suggesting the mechanism is more complex than initially characterized.

Standard Dosing

Research indicates 20-30 mg daily orally, split into 3-4 doses due to very short half-life (~4 hours). Some users prefer sublingual administration for improved bioavailability.

Timing

Split into 3-4 doses throughout the day due to ~4-hour half-life. Example: 7am, 11am, 3pm, 7pm. Avoid late-night dosing as REV-ERB modulation may affect circadian rhythm and sleep.

Cycle Duration

8-12 week cycles. No HPG suppression. Cycling recommended due to limited long-term data.

Side Effects

  • Insomnia or sleep disruption (circadian clock modulation)
  • Anxiety or wakefulness
  • Headache
  • Nausea
  • Potential circadian rhythm disruption with chronic use

Contraindications

  • Circadian rhythm disorders or shift work (may exacerbate disruption)
  • Pregnancy and breastfeeding
  • Individuals under 21
  • Severe insomnia

Best Stacking Partners

Cardarine GW-501516 (complementary fat oxidation pathways)Ostarine (body recomposition — SR-9009 adds metabolic enhancement without suppression)MK-677 (counters potential sleep disruption)

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