Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives Most beginners make one mistake when learning about peptides They focus on which peptide to use, but completely overlook cycle length. C In research and educational discussions, cycle length usually refers to Peptide Therapy in Exeter, NH Exeter Peptide Therapist 40 YEARS OF IGF1: Insulin like growth factors: actions on the skeleton in: Journal of Molecular Endocrinology Volume 61 Issue 1 (2018)