Methods
Age-Related Loss of Muscle Mass
The CALM trial (Counteracting Age-Related Loss of Muscle Mass) was conducted at Bispebjerg Hospital between 2014 and 2018. It was designed as an intention-to-treat randomized controlled study. The study reported in this paper was conducted on a subgroup of subjects, who in addition to the general measurements performed in the CALM trial also participated in an acute 1-day stable isotope tracer infusion trial before and after the intervention. The primary outcome of the study was the comparison of basal overnight fasted muscle protein synthesis rate as well as muscle protein synthesis rate response to protein intake from basal overnight fasted state between baseline and after 12 months. We further explored any sex-specific changes regarding the muscle protein synthesis rates as well as changes in the skeletal muscle metabolome. The exploratory analysis was not pre-specified.Further information and detailed description of the purpose, methods and exclusion criteria in the CALM trial has been published previously [