Left femoral quadriceps was sectioned transversely in half, with the proximal half placed in O.C.T (Tissue-Tek®; Sakura, Netherlands) at −25°C. The tissues were sliced at 10 μm thickness using a cryostat (Leica CM1850, Leica Biosystems, Germany), immediately placed on silanized slide and fixed for 1 h in acetone at −80°C. The tissue sections were stained with HE according to standard histological technique and evaluated histologically in a blinded manner. The following parameters were evaluated and classified as absent, mild, moderate, or intense: fiber atrophy (morphological alteration), muscle necrosis/degeneration, inflammatory infiltrate in the endomysium/perimysium, endomysium/perimysium distension. These criteria were first described by Rizo-Roca et al. (2015).