What the Science Says

SLU-PP-332 is a first-in-class ERRα (Estrogen-Related Receptor Alpha) agonist, discovered by researchers at Saint Louis University. It mimics the effects of endurance exercise by boosting mitochondrial function, fat oxidation, and aerobic capacity.

• Mechanism: Activates ERRα, a key regulator of mitochondrial biogenesis (similar to the effects of cardio training).

• Animal Studies:

  • Mice given SLU-PP-332 showed 70% increased endurance (running time) without training.

  • Increased fat burning & reduced obesity in metabolic disease models.

  • Muscle fiber shifts toward slow-twitch (Type I), enhancing stamina.

• No human trials yet – All data is from rodent studies (2021–2023).

How People Are Using It (Anecdotal Reports)

Since SLU-PP-332 is preclinical, human use is experimental and off-label. Early adopters (mostly biohackers and athletes) report:

• Dosing:

o 0.1–0.3 mg/kg body weight (some extrapolating from mouse studies).

o Example: A 70 kg (154 lb) person might try 7–21 mg per dose.

o Frequency: 2–3x/week (half-life is unclear in humans).

• Stacking:

o With cardarine (PPARδ agonist) for enhanced endurance.

o With AMPK activators (e.g., berberine, AICAR) for fat loss.

• ROA (Route of Administration):

o Most use subcutaneous (SubQ) or intramuscular (IM) injections (oral bioavailability unknown).

📊 Anecdotal Reviews & Effects

From early user reports (Reddit, forums, biohacker communities):

✅ Reported Benefits:

• Increased endurance (longer workouts, less fatigue).

• Fat loss (especially visceral fat, like Cardarine).

• Improved recovery (less DOMS after training).

• Mental clarity (ERRα is also active in the brain).

❌ Reported Side Effects:

• Heart palpitations (ERRα is highly expressed in cardiac muscle).

• Insomnia (if dosed too late in the day).

• Unknown long-term risks (no human toxicity studies).

⚠️ Major Risks & Unknowns

1. Cardiac Stress – ERRα activation could overwork the heart (risk of hypertrophy or arrhythmia).

2. Cancer Concerns – ERRα is upregulated in some cancers (breast, prostate).

3. No Human Safety Data – Dosing is purely speculative.

Future Potential

If human trials confirm safety, SLU-PP-332 could be a game-changer for:

• Metabolic diseases (obesity, diabetes).

• Age-related muscle loss (sarcopenia).

• Athletic performance (endurance sports).

Bottom Line

• Promising but highly experimental – Only for those comfortable with self-experimentation.

• Start low (≤10 mg/dose) and monitor heart rate/side effects.

• Not a substitute for exercise (but could help those unable to train).

Next a look into Fast twitch muscle fiber type II muscle for speed and explosiveness