Marked losses of computed tomography–derived skeletal muscle area and density over the first month of a critical illness are not associated with energy and protein delivery

•Marked losses in computed tomography (CT) muscle area were observed over the first month of critical illness•Losses in CT muscle area were attenuated from week 5- 7 of critical illness•Energy and protein delivery were not associated with the degree of CT-derived muscle loss•Days receiving insulin and sedation were associated with CT-derived muscle loss