Characteristics of 
muscle mass
A total of 90 individuals (31 men and 59 women) in two groups (Flowchart for CALERIE participants who underwent muscle biopsies and percentage change of calorie intake and change of muscle mass, weight, and muscle strength in CR and AL. (a) The flow‐chart shows the 90 CALERIE participants randomly assigned to a CR and AL who underwent at least one muscle biopsy (baseline, 12‐month [12 mo], 24‐month [24 mo]). Of note, two individuals in the CR group underwent a muscle biopsy starting at the 12‐month follow‐up only. (b) Box plot showing percentage calorie intake reduction between baseline and 12‐month (Quantitative characteristics of CALERIE muscle study participants at baseline.Two participants from the CR group did not consent to muscle biopsy at baseline.Changes of muscle mass (leg lean mass by DXA), weight, and two muscle strength variables (average power and peak torque in isokinetic dynamometry at 60 and 180°s