Research

Energy balance

Endurance training increases intramyocellular lipid (IMCL) content, which serves as a readily available energy source for mitochondrial oxidation during prolonged exercise.

If you engage in endurance exercise, your muscles will store more fat to use as fuel. This is a normal and beneficial adaptation, not a sign of poor health.

GoodSupportsHIGH confidence
IMCL content is increased in the trained state to optimally match fat oxidative capacity and that it serves as readily available fuel.
Vera B. Schrauwen‐Hinderling et al. · Obesity · 2006

Why this rating

Multiple methods (EM, MRS, Histochemistry) consistently show increased IMCL in trained subjects.

Source

Intramyocellular Lipid Content in Human Skeletal Muscle

Vera B. Schrauwen‐Hinderling et al. · Obesity · 2006

DOI 10.1038/oby.2006.47

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DOI resolved against Crossref · corpus check 2026-06-10

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