All the hype about peptides But what are they actuallyand have they really been tested in humans for muscle building or tendon regeneration? We took a deep dive into the literature BPC 157 is being promoted across podcasts, wellness clinics, and social media as a powerful healing peptide said to repair tendons, reduce inflammation, and speed recovery from injury. But when Flynn McGuire, a Stable Gastric Pentadecapeptide BPC 157 and Striated, Smooth, and Heart Muscle BPC 157: Experimental Peptide Creates Risk for Athletes