Glossary
Cycle
A defined period of peptide or compound administration, typically followed by an equal or longer period off to prevent desensitization or maintain receptor sensitivity.
Also known as:
cycling on-cycle off-cycle
Peptide cycles vary significantly by compound. Some peptides like BPC-157 are commonly run for 4–8 weeks continuously, while GH secretagogues (GHRPs, GHRHs) are often cycled 5 days on / 2 days off or 8 weeks on / 4 weeks off to prevent pituitary desensitization.
The rationale for cycling is typically to prevent the body from downregulating receptors in response to constant stimulation — similar to how the pituitary releases GH in natural pulses rather than continuously. Cycle length and structure should be specific to the compound being used.