Source comparison
MK-677 for Athletes: Dosing, Timing, and Regulatory Status Comparison
Mechanism Ghrelin receptor agonist; stimulates endogenous GH pulses Direct GH receptor agonist; replaces natural secretion Endogenous GH/IGF-1 within physiological range Administration Oral; once daily, typically evening Subcutaneous injection; daily or multip
This comparison does not assign a generated winner or score.
- Mechanism
- Ghrelin receptor agonist; stimulates endogenous GH pulses
- Direct GH receptor agonist; replaces natural secretion
- Endogenous GH/IGF-1 within physiological range
- Administration
- Oral; once daily, typically evening
- Subcutaneous injection; daily or multiple times per week
- N/A
- Typical Dose Range
- 12.5–25mg daily
- 2–4 IU daily for performance use
- IGF-1 Increase
- 60–90% above baseline (dose-dependent)
- 100–200%+ above baseline (dose-dependent)
- Baseline physiological variation
- Endogenous GH Suppression
- No. Amplifies natural pulses
- Yes. Negative feedback shuts down pituitary secretion
- WADA Status
- Banned (S2 Peptide Hormones, Growth Factors)
- Permitted
- Primary Athletic Benefit
- Lean mass preservation during deficit; recovery; sleep quality
- Anabolism; lipolysis; recovery
- Training adaptation within genetic potential
- Insulin Sensitivity Impact
- Moderate impairment with chronic use (>8 weeks)
- Significant impairment; dose and duration dependent
- No impairment
- Water Retention
- Moderate (intramuscular and subcutaneous)
- Moderate to high
- Minimal (training-induced glycogen storage)
- Cost (Research Grade)
- $60–120 per month at 25mg daily
- $400–800 per month at 2–4 IU daily
- $0
- Bottom Line
- Offers GH/IGF-1 elevation without injection or prescription but with metabolic trade-offs and competitive sport prohibition. Most useful in caloric deficit, post-injury, or sleep-disrupted training phases.
- Gold standard for GH supplementation but requires injection, medical oversight, and carries higher insulin resistance risk. Banned in all tested sports.
- Maximizes performance within natural limits; no metabolic risks, fully compliant with competitive sport regulations.