Effects of exercise on bone marrow adipose tissue in children with overweight/obesity: role of liver fat

Idoia Labayen; Cristina Cadenas-Sánchez; Fernando Idoate; Luis Gracia-Marco; María Medrano; Víctor Manuel Alfaro-Magallanes; Juan M A Alcantara; Beatriz Rodríguez-Vigil; Maddi Osés; Francisco B Ortega; Jonatan R Ruiz; Rafael Cabeza

doi:10.1210/clinem/dgae547

Effects of exercise on bone marrow adipose tissue in children with overweight/obesity: role of liver fat

J Clin Endocrinol Metab. 2024 Aug 7:dgae547. doi: 10.1210/clinem/dgae547. Online ahead of print.

Authors

Idoia Labayen^{1

2

3}, Cristina Cadenas-Sánchez^{1

2

3

4}, Fernando Idoate⁵, Luis Gracia-Marco^{3

4

6}, María Medrano^{1

2

3}, Víctor Manuel Alfaro-Magallanes^{1

2

7}, Juan M A Alcantara^{1

2

3}, Beatriz Rodríguez-Vigil⁸, Maddi Osés^{1

2}, Francisco B Ortega^{4

3

9}, Jonatan R Ruiz^{3

4

6}, Rafael Cabeza¹⁰

Affiliations

¹ Institute for Sustainability & Food Chain Innovation (IS-FOOD), Department of Health Sciences, Public University of Navarre, 31006 Pamplona, Navarre, Spain.
² IdiSNA, Navarra Institute for Health Research, 31006 Pamplona, Navarre, Spain.
³ Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid, Spain.
⁴ Department of Physical Education and Sports, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain.
⁵ Radiology Department, Mutua Navarra, Department of Health Sciences, Public University of Navarre, 31012 Pamplona, Navarre, Spain.
⁶ Instituto de Investigación Biosanitaria, ibs.Granada, Granada, Spain.
⁷ LFE Research Group, Department of Health and Human Performance, Faculty of Physical Activity and Sport Sciences, Universidad Politécnica de Madrid, Madrid, Spain.
⁸ Department of Magnetic Resonance Imaging, University Hospital of Araba (HUA), Osakidetza Basque Health Service, Osatek, Bioaraba Health Research Institute, 01004 Vitoria-Gasteiz, Alava, Spain.
⁹ Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.
¹⁰ Department of Electrical, Electronic and Communications Engineering, Smart Cities Institute, Public University of Navarre, 31006 Pamplona, Spain.

PMID: 39109799
DOI: 10.1210/clinem/dgae547

Abstract

Context: 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.

Objectives: (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.

Design: Ancillary analysis of a two-arm, parallel, non-randomized clinical trial.

Setting: Primary care centres in Vitoria-Gasteiz (Spain).

Participants: 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].

Interventions: 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).

Main outcomes and measures: 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.

Results: 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.

Conclusions and relevance: 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.

Keywords: MAFLD; MASLD; NAFLD; bone health; fatty liver; lifestyle; obesity; youth.