The elevated concentrations of c-reactive protein [CRP], IL-6, and TNF-α are the indices that most strongly correlate with sarcopenia and frailty, as it is the acute inflammation induced by COVID-19 which promotes mitochondrial damage and interferes with iron homeostasis, thus promoting the decrease in an energy substrate necessary for the functioning of the mitochondria [33,34,35]. The gene discussed is IL6; the disease is sarcopenia.