The Lean Mass Preservation Stack — GLP-1 + Growth Hormone Protocol
A protocol combining a GLP-1/GIP/glucagon triple agonist (retatrutide) with growth hormone secretagogues (ipamorelin + CJC-1295) to achieve aggressive fat loss while preserving lean mass. Addresses the primary limitation of GLP-1 therapy: muscle catabolism during caloric restriction.
Daily Schedule
Timing and dosage for each step
Monday 08:00 AM
8 mg
Once weekly subcutaneous injection (abdomen, thigh, or upper arm). Begin at 2mg/week and titrate over 8 weeks to 8mg. Nausea is common during titration — eat small portions, stay hydrated.
Daily 10:00 PM
200 mcg
Ipamorelin 200mcg subcutaneous before bed. Maximises GH pulse during slow-wave sleep. Critical for lean mass preservation during GLP-1 induced caloric deficit.
Daily 10:00 PM
100 mcg
CJC-1295 100mcg subcutaneous with ipamorelin. Amplifies and extends the GH pulse. The combination produces stronger, longer-lasting GH release than either alone.
Protocol Overview
GLP-1 receptor agonists (semaglutide, tirzepatide, retatrutide) produce powerful fat loss but carry a significant liability: in the absence of resistance training and anabolic support, approximately 25–35% of weight lost on GLP-1 therapy comes from lean mass. Muscle loss accelerates functional decline, reduces metabolic rate, and dramatically increases rebound risk when the drug is discontinued.
This protocol attacks fat loss from two directions while protecting muscle:
Retatrutide: Drives caloric deficit via appetite suppression and enhanced fat oxidation (GLP-1/GIP/glucagon triple agonism). Produces the strongest pharmacological fat loss currently available.
Ipamorelin + CJC-1295: Elevates GH pulsatility during sleep, driving lipolysis (fat burning) and promoting lean mass retention. GH is strongly anti-catabolic — it preserves muscle during caloric restriction.
The Lean Mass Protection Strategy
The combination works through complementary signalling:
- Retatrutide → caloric deficit, appetite suppression, fat oxidation
- GH secretagogues → anabolic signalling, muscle protein synthesis preservation, enhanced lipolysis
- Resistance training (non-negotiable) → primary driver of lean mass retention signal
- High protein intake (1.6–2g/kg lean mass) → substrate for protein synthesis
Titration Schedule
Retatrutide:
- Weeks 1–4: 2mg/week
- Weeks 5–8: 4mg/week
- Weeks 9–12: 8mg/week (maintenance)
Ipamorelin/CJC-1295: Full dose from Day 1.
Monitoring
- Body composition (DEXA scan): monthly
- Fasting glucose and HbA1c: monthly during titration
- Liver enzymes: baseline and 8 weeks
- Subjective energy and recovery: weekly
Resistance Training Requirement
This protocol should never be run without a structured resistance training programme. Minimum 3x/week compound movements. Without the anabolic stimulus from training, even optimal GH levels cannot prevent muscle catabolism during aggressive caloric deficit.
Disclaimer
Retatrutide is not FDA or EMA approved (Phase 3 trials ongoing). Ipamorelin and CJC-1295 are research peptides. This protocol requires physician oversight. For educational purposes only.