Samples were fixed in 10% buffered formalin overnight at 4C, dehydrated with increasing concentrations of ethanol, embedded in paraffin, cut into 5 m sections, and stained with hematoxylin and eosin (HE) or Massons Trichrome Stain Kit (Sigma-Aldrich)
doi: 10.1007/s12011-023-03782-1 81
Seek medical advice if symptoms do not improve, become worse, return, or if new symptoms develop
None of them is FDA-approved for muscle building, several are prohibited in competitive sport, and material sold as "research use only" is not verified for content a published NMR analysis found an undeclared constituent in a custom-synthesised peptide (Choules et al., Journal of Pharmaceutical and Biomedical Analysis , 2020)
What follows is where the distinction becomes actionable
Aging muscles may not lose the signals needed for repair