For lean mass the pair chosen most often is a GHRH analogue such as CJC-1295 with ipamorelin, for fat reduction ipamorelin rather than GHRP-6 because it does not drive up appetite, for a bulking phase GHRP-6, and for recovery after injury BPC-157 and TB-500. Building lean mass, reducing body fat, recovering faster after an injury or simply eating larger portions are four different goals, and different peptides have different mechanisms. There is no "best peptide" without a stated goal. This article shows which category answers which goal and points to the separate articles with the mechanism and the state of research for each.
Building lean muscle mass
One combination comes up again and again here: a GHRH analogue such as CJC-1295 together with a peptide from the GHRP group such as ipamorelin. The two classes act on the pituitary in ways that reinforce each other. The mechanism of that synergy, and why this particular pair is combined most often, is explained in the article on CJC-1295 and ipamorelin. The difference between the extended-action version of CJC-1295, the one with DAC, and the short-acting version is covered in the article on CJC-1295 with or without DAC. In the shop the pair is made up of CJC-1295 and ipamorelin, and both peptides in a single vial are sold as ipamorelin and CJC-1295 combo.
Fat reduction and body recomposition
With the goal of less fat and preserved muscle, what matters is that the peptide does not drive up appetite. That is why ipamorelin is often preferred over GHRP-6, which strongly stimulates hunger. The differences between the GHRP peptides on this point are set out in the article on GHRP-2, GHRP-6, ipamorelin and hexarelin. The molecules aimed directly at body weight are a separate group, described in the article on GLP-1 and incretins.
Increasing appetite in a bulking phase
If your problem is eating enough calories rather than burning them, GHRP-6 works the other way round from the goal above: its effect on ghrelin and appetite becomes an advantage rather than an obstacle. The same map of differences linked above shows why GHRP-6 and ipamorelin give opposite effects on hunger despite a similar basic mechanism.
Recovery after injury and support for connective tissue
Tendons, ligaments and muscle tissue after an injury belong to a different group of peptides, BPC-157 and TB-500, with a different mechanism from GHRH and GHRP. It is not about growth hormone but about angiogenesis and the migration of repair cells. The mechanism and what the research actually showed, mostly in animals, is described in the article on recovery peptides, and what that means for injuries specifically in the article on peptides and tendon and ligament injuries. Vials of BPC-157 and TB-500 are in the recovery peptides category.
Peptides prohibited in sport: what to keep in mind
Before you choose a peptide for training, check whether you compete in a sport under anti-doping control. BPC-157 and TB-500 are on the World Anti-Doping Agency prohibited list all year round, and a ban can be imposed even without a positive test. The details are in the article on the WADA ban on BPC-157 and TB-500.
Before you start: safety and legal status
Most of the peptides in this article are not approved medicines, and their long-term safety in humans has not been described in controlled clinical trials. That applies to the GHRH and GHRP group as much as to BPC-157 and TB-500. Consult a doctor before use, particularly if you have a chronic condition. The full picture is in the article on the legal status of peptides.
Frequently asked questions
Can several peptides be combined at once?
Yes, some combinations such as GHRH with GHRP are put together precisely because they reinforce each other. Combining also increases the number of unknown interactions, which is why it calls for a doctor's advice first.
Which peptide is the strongest?
"Strongest" does not mean "best for your goal". In terms of peak growth hormone concentration, GHRP-2 is regarded as the most potent of the GHRP group, and no direct comparison of the potency of hexarelin against GHRP-2 in humans has been published. A stronger single surge can be a worse long-term choice than the gentler ipamorelin.
Will peptides replace training and diet?
No. Peptides modulate processes that are already taking place in the body in response to training and nutrition. Without the training and the diet there is nothing for them to amplify.
Sources
- WADA Prohibited List 2026, Polish translation, Polish Anti-Doping Agency (POLADA). https://antydoping.pl/wp-content/uploads/2025/12/2026_Lista-zabroniona.pdf
- BPC-157: What Athletes Should Know About the Prohibited Experimental Peptide. U.S. Anti-Doping Agency (USADA). https://www.usada.org/spirit-of-sport/bpc-157-peptide-prohibited/