*4.2. Body Composition, Metabolic Rate, and In Vivo Muscle Function*

Body composition (for lean and fat content) was measured by quantitative magnetic resonance analysis (EchoMRI-100TM, Echo Medical System, Houston, TX, USA) [13,23]. Resting metabolic rate was assessed by using Oxymax calorimetry (Columbus Instruments, Columbus, OH, USA) during the daytime (0900-1700) [13]. At the end of the study, rotarod activity (model RRF/SP, Accuscan Instrument, Columbus, OH, USA) and forelimb grip strength (Model 47106, UGO Basile, Gemonio, Italy) in mice were assessed [13,23].
