FitnessSupplement GuideAug 2026

Best Peptides for Muscle Growth in 2026: The Reddit Answer

Ask Reddit for the best peptides for muscle growth and a familiar shortlist comes back. CJC-1295 with ipamorelin, MK-677, tesamorelin, and BPC-157 with TB-500, with myostatin blockers further down the replies. This page sets those names against published studies, one row per study, printing who was enrolled, what was measured, what the number came back as, and the design behind it. The searches behind the table are printed at the end with their dates.

The Reddit Shortlist, Study by Study

One row is one study, so a compound with several trials gets several rows. Read the population column before the result column: a change measured in patients with HIV, in postmenopausal women or in rats belongs to those people and those animals.

Compound	Population (n)	What was measured	Result	Design	PMID
Growth hormone (rhGH)	16 men aged 21 to 34 on an identical resistance programme	Quadriceps protein synthesis rate, limb circumferences, strength, fat free mass	Fat free mass and total body water rose more with rhGH (P less than 0.01). Quadriceps protein synthesis, circumferences and strength rose similarly in both groups.	Randomised, placebo controlled, 12 weeks	1550219
Growth hormone (rhGH)	18 healthy men aged 65 to 82, pre-trained for 14 weeks	One repetition maximum strength, DXA body composition, IGF-I	IGF-I rose to 255 micrograms per litre against 119 on placebo. No effect on muscle strength at any time.	Double blind, placebo controlled, 10 further weeks	7525633
Growth hormone (rhGH)	31 healthy men, mean age 74, in four arms	Isokinetic quadriceps strength, power, cross sectional area, fibre size	rhGH alone left strength, power, cross sectional area and fibre size unchanged. Training plus placebo raised strength, power and cross sectional area, and rhGH did not augment those gains.	Randomised, placebo controlled, blinded, 12 weeks	11836279
Growth hormone (rhGH)	96 recreationally trained athletes, 63 men and 33 women, mean age 27.9	Lean body mass, extracellular water, dead lift, jump height, sprint capacity	Lean body mass rose through an increase in extracellular water. Sprint capacity rose 3.9 percent (95 percent CI 0.0 to 7.7) and had gone 6 weeks after stopping. Other measures did not change significantly.	Randomised, placebo controlled, blinded, 8 weeks	20439575
Growth hormone (rhGH)	18 study populations, 220 treated participants, mean age 69	Lean body mass, fat mass, weight, adverse events	Lean body mass rose 2.1 kg (95 percent CI 1.3 to 2.9), fat mass fell 2.1 kg, weight changed 0.1 kg (P equals 0.87). Significantly more soft tissue edema and arthralgias.	Systematic review of randomised controlled trials	17227934
CJC-1295 (with DAC)	Healthy subjects aged 21 to 61	Peak concentration and area under the curve of growth hormone and IGF-I	Growth hormone rose 2 to 10 fold for 6 days or more, IGF-I 1.5 to 3 fold for 9 to 11 days. Estimated half life 5.8 to 8.1 days.	Two randomised, double blind, ascending dose trials	16352683
Ipamorelin	Eight healthy men at each of five infusion rates	Concentrations of ipamorelin and of growth hormone	Terminal half life about 2 hours, clearance 0.078 L/h/kg. Growth hormone peaked at 0.67 hours.	Dose escalation pharmacokinetic and pharmacodynamic trial	10496658
[Nle27]GHRH(1-29)NH2	10 women and 9 men aged 55 to 71	Nocturnal growth hormone, IGF-I, DXA body composition	Nocturnal growth hormone rose in both groups. Lean body mass rose in men only (P less than 0.05), with no other body composition change.	Single blind, randomised, placebo controlled, 16 weeks	9141536
Tesamorelin	412 patients with HIV and accumulated abdominal fat	Percent change in visceral adipose tissue on computed tomography	Visceral adipose tissue fell 15.2 percent against a 5.0 percent rise on placebo (P less than 0.001). IGF-I rose 81.0 percent.	Randomised, placebo controlled, 26 weeks	18057338
Tesamorelin	Adults with HIV pooled across five randomised trials	Visceral adipose tissue, trunk fat, hepatic fat, lean body mass	Lean body mass rose 1.42 kg (95 percent CI 1.13 to 1.71, P less than 0.001) and visceral adipose tissue fell 27.71 cm2.	Meta-analysis of randomised controlled trials	41545261
MK-677 (ibutamoren)	65 healthy adults aged 60 to 81	Fat free mass and visceral fat at 1 year, isokinetic strength, function	Fat free mass rose 1.1 kg against a 0.5 kg fall on placebo (P less than 0.001). The paper states the increase did not result in changes in strength or function. Insulin sensitivity decreased.	2 year, double blind, randomised, placebo controlled	18981485
MK-677 (ibutamoren)	123 elderly hip fracture patients, 62 on drug and 61 on placebo	Objective functional performance measures and blood IGF-1	Gait speed improved by a 0.7 score difference in the means (P equals 0.011). Stair climbing power changed 12.5 W (P equals 0.292). Stopped early on a heart failure signal.	Randomised, double blind, placebo controlled phase IIb	21067829
BPC-157 and TB-500	32 male Sprague-Dawley rats with transected and repaired Achilles tendons	Maximum load to failure, Bonar and Movin histology scores	Load to failure rose in both treated groups, reaching significance for TB-500 (p less than 0.05), which also lowered Bonar (p equals 0.016) and Movin scores (p equals 0.017). BPC-157 totals were numerically lower.	Randomised four arm rat study, four weeks	42542926
ACE-031 (activin receptor IIB)	48 healthy postmenopausal women randomised 3 to 1	Total body lean mass by DXA, thigh muscle volume by MRI	At day 29 in the top dose group, lean mass rose 3.3 percent and thigh muscle volume rose 5.1 percent, both at P equals 0.03.	Double blind, placebo controlled, single ascending dose	23169607

Growth Hormone Alongside a Training Programme

Several growth hormone trials paired an injected hormone with a training programme, a design the forum argument implies. Yarasheski trained 16 men identically for 12 weeks and reported fat free mass and total body water rising more with the hormone while quadriceps protein synthesis, circumferences and strength rose the same in both groups (PMID 1550219).

Fat free mass counts water

Meinhardt gave growth hormone to recreationally trained athletes and reported lean body mass rising through an increase in extracellular water, with sprint capacity rising and the other performance measures unchanged (PMID 20439575). A systematic review recorded lean body mass rising while body weight stayed statistically unchanged, alongside more soft tissue edema and arthralgias (PMID 17227934).

Protein intake and creatine are argued on trials that used strength itself as an endpoint.

The Secretagogues Reddit Names

The CJC-1295 numbers belong to the DAC form, a different molecule from the short acting no-DAC version usually paired with ipamorelin in the threads (PMID 16352683).

Khorram ran a body composition endpoint on a releasing hormone analog in age advanced adults, where the lean body mass increase appeared in the men and the skin thickness increase in both (PMID 9141536). Profiles for CJC-1295 with DAC and tesamorelin sit in the library.

Thymosin Beta-4, TB-500 and BPC-157

For BPC-157 and TB-500 together, the cited experiment ran in rats with transected and surgically repaired Achilles tendons (PMID 42542926). A 2026 development review of BPC-157 describes the available clinical data as coming from uncontrolled pilot studies, and reports a plasma half life under 30 minutes with intramuscular bioavailability of 14 to 51 percent depending on species (PMID 42198317). A 2026 Sports Medicine review covers mechanisms, safety and regulatory status for peptides marketed direct to patients, and discusses the placebo effect and how social media amplifies it (PMID 41966639). The recovery argument, that faster healing allows more training rather than the peptide adding tissue, sits in the recovery stack guide.

The Dose Figures Behind Those Trials

The growth hormone training trials used these study drug doses of injected recombinant human growth hormone:

Yarasheski 1992: 40 micrograms per kg per day for 12 weeks. Taaffe 1994: 0.02 mg per kg per day. Lange 2002: a final dose of 1.77 IU per day, about 7.2 micrograms per kg per day. Meinhardt 2010: 2 mg per day for 8 weeks.

Disclaimer: trial doses of an injected hormone, given under supervision, in the populations listed in the table, and not doses of any peptide. The 2007 review concluded that growth hormone cannot be recommended as an antiaging therapy (PMID 17227934).

The tesamorelin and MK-677 trials used a fixed study drug dose:

Falutz 2007, tesamorelin: 2 mg daily by subcutaneous injection for 26 weeks. Nass 2008 and Adunsky 2011, MK-677: 25 mg orally once daily.

Disclaimer: the tesamorelin figure belongs to one approved indication in patients with HIV. The MK-677 figure belongs to a trial in which insulin sensitivity decreased, and to a hip fracture trial stopped early on a heart failure signal. Neither is a recommendation.

The Searches That Produced This Table

Each line is a fact about a query, not about the world. A different query string returns a different set.

("CJC-1295" OR ipamorelin OR "MK-677" OR ibutamoren OR tesamorelin OR "BPC-157" OR "TB-500") AND (hypertrophy OR "muscle strength" OR "cross-sectional area") AND randomized controlled trial[pt] in PubMed on 9 August 2026 returned 2 records, PMID 38905488 and PMID 21067829.
"BPC-157" in PubMed on 9 August 2026 returned 225 records. The same query with AND randomized controlled trial[pt] appended, same date, returned 0.
"TB-500" in PubMed on 9 August 2026 returned 24 records, read through their summaries: the rat tendon study, four narrative reviews, doping control and analytical chemistry papers, and eight records matching the string incidentally, among them a chicken feed study.
sermorelin AND (muscle OR "lean body mass" OR "body composition") in PubMed on 9 August 2026 returned 16 records, while the entry term form "GHRH(1-29)NH2" AND (muscle OR "body composition" OR "lean body mass") returned 3 that day, one being PMID 9141536 above. A trade name and an entry term are different searches.
"IGF-1 LR3" OR "IGF-I LR3" OR "long R3 IGF-1" returned 49 records and follistatin AND (hypertrophy OR "muscle strength" OR "lean body mass") AND humans[mh] returned 92, both in PubMed on 9 August 2026. Neither returned a record meeting the criteria for a row here: a named population, a stated endpoint, a reported result.

The Question That Comes Before the Dose

Every figure above belongs to a study drug prepared to a specification and assayed before use. A research grade vial bought on a forum recommendation is not dispensed through a pharmacy, so the milligram on its label is a claim by whoever printed it.

Reading a certificate of analysis is covered in the COA verification guide, the testing houses in the labs comparison, and the local picture in the Vietnam sourcing guide. For mechanism, start with the HGH peptides guide or the profiles in the peptide library.

Frequently Asked Questions

Reddit lists MK-677 next to injectable peptides. Is it the same kind of compound?

They are different molecules given by different routes. The 2008 trial describes MK-677 as an oral ghrelin mimetic (PMID 18981485), a non-peptide swallowed once a day. CJC-1295 is a long acting analog of growth hormone releasing hormone, given by subcutaneous injection (PMID 16352683), and ipamorelin is a growth hormone releasing peptide, delivered in its human pharmacokinetic trial as a 15 minute infusion (PMID 10496658). All three raised growth hormone in the people they were tested in. Sharing an axis is not the same as sharing a molecule, a route or an endpoint.

The BPC-157 and TB-500 study cited here ran in rats. What does that design let a reader conclude?

It answers a tendon repair question rather than a muscle growth one. The rats had their Achilles tendons transected and surgically repaired before treatment began, treatment ran intraperitoneally for four weeks, and the endpoints were maximum load to failure and histology scoring (PMID 42542926). The paper also reports that combining BPC-157 with TB-500 conferred no additional benefit over either compound given alone, and its authors describe the model as exploratory and call for dose optimisation and longer term work.

Is TB-500 the same molecule as thymosin beta-4?

They are related but not identical. Thymosin beta-4 is a naturally occurring 43 amino acid peptide, trialled in people as a topical treatment: 73 patients with venous stasis ulcers across eight European sites, where complete healing within 3 months was reached in about 25 percent of patients (PMID 20536470). TB-500 is a veterinary preparation whose key ingredient is the segment 17 to 23 of that protein, LKKTETQ, acetylated at the N-terminus, a segment that paper describes as responsible for actin binding, cell migration and wound healing (PMID 23084823).

Does a peptide that raises growth hormone produce the same result as injecting growth hormone?

They act at different points on one axis. A secretagogue prompts the pituitary, so the CJC-1295 and ipamorelin papers report concentration curves (PMID 16352683, PMID 10496658). Injected growth hormone supplies the hormone directly, and those trials gave it alongside a training programme, with strength, cross sectional area and sprint capacity among the endpoints (PMID 1550219, PMID 11836279, PMID 20439575). Reading across is an inference about a shared pathway, not a result carried over.

Where is tesamorelin approved, and for what?

A 2012 review in Annals of Pharmacotherapy describes tesamorelin as approved by the US Food and Drug Administration in November 2010 for lipodystrophy associated with HIV infection, on the strength of two phase 3 trials and their pooled analyses, which reduced waist circumference and visceral adipose tissue over 26 weeks (PMID 22298602). That is a statement about one regulator and one indication. Status in Vietnam is a separate question with a separate source, and a decision about a diagnosed condition belongs with a doctor.

What would a study have to look like to answer the muscle question directly?

Trained adults, random allocation, a placebo arm, the same training programme in both arms, and an endpoint measured on the muscle itself rather than on whole body composition: cross sectional area by imaging, fibre size on biopsy, or one repetition maximum strength. Lange imaged quadriceps cross sectional area and measured fibre size (PMID 11836279), and the 1992 Yarasheski trial measured quadriceps protein synthesis rate directly (PMID 1550219).

Not medical advice. Consult a healthcare professional before starting any supplement or protocol.