Research

Hormonal

Metabolic switching (the dynamic capacity of skeletal muscle to switch between fat and carbohydrate oxidation) is an intrinsic property of skeletal muscle cells, independent of neuroendocrine influences, and mirrors the donor's in vivo insulin sensitivity and metabolic flexibility.

Your body's ability to switch between burning fat and carbs is largely determined by your muscle cells' intrinsic properties, which are linked to your genetic makeup and past metabolic history. This means that 'metabolic flexibility' isn't just about what you eat today, but how your muscle cells are wired. If you struggle with fat oxidation, it may be an intrinsic cellular trait rather than just a lack of willpower, suggesting that personalized approaches based on metabolic phenotype may be more effective than generic advice.

GoodSupportsHIGH confidence
The interindividual variability in metabolic phenotypes was preserved in human myotubes separated from their neuroendocrine environment, which supports the hypothesis that metabolic switching is an intrinsic property of skeletal muscle.
Barbara Ukropcová et al. · Journal of Clinical Investigation · 2005

Why this rating

High-quality in vitro human primary myocyte culture study with strong correlations to in vivo clinical phenotypes, though limited by small sample size (n=16).

Source

Dynamic changes in fat oxidation in human primary myocytes mirror metabolic characteristics of the donor

Barbara Ukropcová et al. · Journal of Clinical Investigation · 2005

DOI 10.1172/jci24332

cross_sectional · n=16Cited 212×
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DOI resolved against Crossref · corpus check 2026-06-10

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