IGF-1 DES (1-3): A Tracking Guide for a Truncated IGF Variant

IGF-1 DES (1-3) is a truncated form of insulin-like growth factor 1, missing the first three amino acids at the N-terminus. That small change reduces its binding to IGF binding proteins, which in turn increases its free, active fraction at the site of injection. The practical theory among self-experimenters is that it works more locally than full-length IGF-1 or IGF-1 LR3, making site-injection appealing for muscle work.

The human evidence is limited. The biochemistry is real; the clinical claims are not.

What it does

• Binds the IGF-1 receptor with higher potency than native IGF-1 at the local site
• Half-life is short (around 20-30 minutes in circulation)
• Reduced IGFBP binding means more free peptide where it lands
• Promotes satellite cell activation and protein synthesis in muscle (preclinical)

Typical protocol shape

Commonly reported in self-experimenter circles:

• 50-150 mcg per injection
• Site-injected into worked muscle, often pre- or post-training
• Short cycles (4-6 weeks)
• Defined off periods to avoid receptor adaptations

Because the half-life is so short, dosing strategy is more about timing relative to the workout than total daily exposure.

What to track daily

• Dose, exact site, time relative to training
• Hypoglycemia symptoms (less likely than LR3 but possible at higher doses)
• Local soreness or pump quality
• Energy and mood
• Sleep quality

What to track weekly

• Bodyweight
• Tape measurements of injected muscle groups (and a control group)
• Strength on key lifts
• Photos under consistent lighting

The control-muscle measurement is the most important habit for IGF-1 DES specifically. If only injected sites grow more than uninjected ones (relative to training), the site-injection theory has some support in your own data. If everything grows together, you are mostly seeing training response.

Bloodwork worth doing

• Baseline: fasting glucose, insulin, HbA1c, IGF-1, lipid panel
• Mid-cycle: same
• IGF-1 may not move dramatically given the short half-life and local action

Realistic expectations

• Localized pump and soreness changes are commonly reported
• Site-specific hypertrophy claims are hard to prove and easy to imagine
• Strength changes, if any, are modest within a cycle
• No reliable evidence for fat-loss claims

Common mistakes

• No control muscle to compare
• Injecting into the same site repeatedly (scar tissue)
• Stacking with LR3 and crediting DES
• Ignoring training and nutrition as the dominant variables

A tracking template

• Daily: dose, site, training session, hypoglycemia notes
• Weekly: weight, tape measurements (worked and control sites), strength
• Monthly: fasting glucose, IGF-1
• Photos every 2 weeks

Peptid AI lets you log injection sites and tag training sessions, which makes the site-vs-control comparison easier to actually do.

Safety notes

Long-term IGF receptor stimulation has theoretical cancer-promotion concerns. Hypoglycemia is less of an issue than with LR3 but still possible. Anyone with a personal or family history of hormone-sensitive cancers should not be self-experimenting here.

Peptid AI is an educational and self-tracking tool. Nothing in this post is medical advice. Doses mentioned reflect what is commonly reported in research literature — they are not recommendations. Always consult a qualified physician before starting, changing, or stopping any protocol.