%0 Journal Article
%T Effects of exercise on bone marrow adipose tissue in children with overweight/obesity: role of liver fat.
%A Labayen I
%A Cadenas-Sánchez C
%A Idoate F
%A Gracia-Marco L
%A Medrano M
%A Alfaro-Magallanes VM
%A Alcantara JMA
%A Rodríguez-Vigil B
%A Osés M
%A Ortega FB
%A Ruiz JR
%A Cabeza R
%J J Clin Endocrinol Metab
%V 0
%N 0
%D 2024 Aug 7
%M 39109799
%F 6.134
%R 10.1210/clinem/dgae547
%X <B>BACKGROUND: </B>Exercise reduces adiposity, but its influence on bone marrow fat fraction (BMFF) is unknown; nor is it known whether a reduction in liver fat content mediates this reduction.<BR><B>OBJECTIVE: </B>(i) To determine whether incorporating exercise into a lifestyle program reduces the lumbar spine (LS)-BMFF, and (ii), to investigate whether changes in liver fat mediate any such effect.<BR><B>METHODS: </B>Ancillary analysis of a two-arm, parallel, non-randomized clinical trial.<BR><B>METHODS: </B>Primary care centres in Vitoria-Gasteiz (Spain).<BR><B>METHODS: </B>A total of 116 children with overweight/obesity were assigned to a 22-week family-based lifestyle program (control group [n=57]) or the same program plus an exercise intervention (exercise group [n=59].<BR><B>METHODS: </B>The compared interventions consisted of a family-based lifestyle program (two 90-minute sessions/month) and the same program plus supervised exercise (three 90-minute sessions/week).<BR><B>METHODS: </B>The primary outcome examined was the change in LS-BMFF between baseline and 22 weeks, as estimated by MRI. The effect of changes in hepatic fat on LS-BMFF were also recorded.<BR><B>RESULTS: </B>Mean weight loss difference between groups was 1.4±0.5 kg favour of the exercise group. Only the children in the exercise group experienced a reduction in LS-BMFF (effect size [Cohen d] -0.42, CI: -0.86, -0.01). Importantly, 40.9% of the reductions in LS-BMFF were mediated by changes in percentage hepatic fat (indirect effect: β=-0.104, 95%CI=-0.213, -0.019). The impact of changes in hepatic fat on LS-BMFF was independent of weight loss.<BR><B>CONCLUSIONS: </B>The addition of exercise to a family-based lifestyle program designed to reduce cardiometabolic risk improves bone health by reducing LS-BMFF in children with overweight or obesity. This beneficial effect on bone marrow appears to be mediated by reductions in liver fat.