The RCT study
MRS
Participants were from the RCT Generation 100 study (NCT01666340, ClinicalTrials.gov registry) which originally set out to evaluate the effect of 3 years of supervised exercise training versus following the national physical activity guidelines on morbidity and mortality in older adults. The MRS acquisition was planned to be an outcome after end of the intervention at 3 years. At 3 years, the study period was extended to 5 years due to lower mortality in the cohort than anticipated based on national numbers [All inhabitants of Trondheim, Norway, born between 1936 and 1942 registered in the National Population Registry (Participants were stratified by sex and cohabitation status before being randomized into a supervised exercise group performing either high-intensity interval training (HIIT) (