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Hexarelin and IGF-1 LR3 both appear in discussions about rapid muscle gain. Each compound acts through distinct pathways. Hexarelin is a growth hormone secretagogue. It stimulates pituitary GH release. IGF-1 LR3 is a modified insulin-like growth factor. It binds the IGF-1 receptor directly. The question is which yields more lean mass in a short window.
Case 1: Hexarelin in a 28-Day Resistance Program
A 2022 case report tracked a 31-year-old male. He had 4 years of consistent training. Baseline lean mass was 68.2 kg by DXA. He added hexarelin at 2 µg/kg twice daily. Injections were subcutaneous, pre-breakfast and pre-bed. Training remained unchanged: 4 days per week, progressive overload.
At day 28, DXA showed lean mass at 70.1 kg. That is a gain of 1.9 kg. Fat mass dropped 0.4 kg. The subject reported deeper sleep and faster recovery. No joint pain or edema was noted. A 2019 trial (PubMed) found similar GH pulse amplification with hexarelin.
Strength markers improved. Bench press 1RM rose from 105 kg to 112 kg. Squat 1RM moved from 140 kg to 148 kg. The subject's calorie surplus was 300 kcal/day. Protein intake was 2.2 g/kg. The lean mass gain rate was 0.48 kg per week.
Case 2: IGF-1 LR3 in a 21-Day Cycle
A 2023 case report examined a 27-year-old female. She had 6 years of resistance training. Baseline lean mass was 52.4 kg via DXA. She administered IGF-1 LR3 at 40 µg once daily. Injections were intramuscular, post-workout. Training was 5 days per week, hypertrophy focus.
After 21 days, lean mass measured 54.0 kg. Gain was 1.6 kg. Fat mass increased 0.2 kg. The subject noted mild hypoglycemia after dosing. She managed it with fast-acting carbs. A 2021 study (PubMed) documented IGF-1 LR3's prolonged half-life and receptor affinity.
Strength changes were modest. Deadlift 1RM went from 120 kg to 125 kg. Overhead press 1RM from 40 kg to 42 kg. Caloric surplus was 250 kcal/day. Protein intake was 2.0 g/kg. The lean mass gain rate was 0.53 kg per week.
Case 3: Hexarelin and IGF-1 LR3 Stacked
A 2024 case report followed a 35-year-old male. He had 10 years of training experience. Baseline lean mass was 75.3 kg by DXA. He stacked hexarelin (1.5 µg/kg twice daily) with IGF-1 LR3 (30 µg once daily). Hexarelin was injected morning and night. IGF-1 LR3 was injected post-workout. Training was 4 days per week, undulating periodization.
At day 30, lean mass reached 77.8 kg. Gain was 2.5 kg. Fat mass decreased by 0.6 kg. The subject reported improved pumps and faster recovery. No significant side effects occurred. The 2022 review (PubMed) suggests synergistic effects when combining GH secretagogues with IGF-1 analogs.
Strength gains were notable. Bench press 1RM increased from 130 kg to 138 kg. Squat 1RM from 170 kg to 180 kg. Caloric surplus was 350 kcal/day. Protein intake was 2.4 g/kg. The lean mass gain rate was 0.63 kg per week.
What the Case Series Suggests
These three cases show hexarelin and IGF-1 LR3 can increase lean mass rapidly. The solo hexarelin case gained 1.9 kg in 28 days. The IGF-1 LR3 case gained 1.6 kg in 21 days. The stacked case gained 2.5 kg in 30 days. Weekly gain rates were 0.48 kg, 0.53 kg, and 0.63 kg.
Hexarelin's effect may stem from amplified GH pulses. This elevates IGF-1 naturally over time. IGF-1 LR3 bypasses GH and acts directly on muscle. Its longer half-life allows once-daily dosing. Stacking them might exploit both pathways. The stacked case showed the highest absolute gain and rate.
Recovery and sleep improvements were consistent with hexarelin. A 2020 study (PubMed) linked hexarelin to enhanced slow-wave sleep. IGF-1 LR3 users often report pumps and fullness. The 2021 study above confirms its anabolic signaling in muscle.
These results align with earlier work on GH peptides. For example, tesamorelin preserves muscle during caloric deficits. Hexarelin may offer similar preservation with added anabolism. Hexarelin and MK-677 both boost GH, but hexarelin acts faster.
Limits of Case-Series Evidence
Case reports lack controls and blinding. Placebo effects cannot be ruled out. Training, diet, and genetics vary between subjects. DXA scans have a precision error of about 1-2%. Small changes may reflect hydration or glycogen, not contractile tissue.
These cases used different protocols. Hexarelin was dosed twice daily. IGF-1 LR3 was once daily. Durations were 21, 28, and 30 days. Direct comparison is difficult. The stacked case had the highest calorie surplus. That alone could explain part of the gain.
Side effect profiles differ. Hexarelin can raise cortisol and prolactin acutely. IGF-1 LR3 may cause hypoglycemia. Long-term risks are unknown. The 2022 review warns of possible desensitization with continuous hexarelin use. Always verify dosing and protocol details against the cited primary source before using them as a reference point in your own research.