IL6 and COVID-19: Elevated levels of pro-inflammatory molecules including IFN-g, IL-1b, IL-6, IL-17, and TNF-a can directly impact skeletal muscle by muscle fiber proteolyzing and disturbing protein synthesis.109 Furthermore, corticosteroids that are used for the reduction of inflammation in COVID-19 patients can induce musculoskeletal impairments.109 Reduced bone mineral density has been also reported in patients as an adverse effect of corticosteroid which is dependent on the extent and duration of treatment with corticosteroids.109