Research

Hormonal

A 12-week resistance exercise program increases lean body mass and hepatic insulin sensitivity in obese adolescents without causing weight loss or reducing body fat.

If you are obese and sedentary, start a resistance training program twice a week. You don't need to diet or lose weight for this to work. You will likely gain muscle and improve your liver's ability to handle insulin, which is a key metabolic health marker. Don't worry if the scale goes up slightly; that is likely muscle, not fat.

GoodSupportsMEDIUM confidence
We conclude that a controlled resistance exercise program without weight loss increases strength and lean body mass, improves hepatic insulin sensitivity, and decreases GPR without affecting total fat mass or visceral, hepatic, and intramyocellular fat contents.
Gert‐Jan van der Heijden et al. · Medicine & Science in Sports & Exercise · 2010

Why this rating

Small sample size (n=12) and lack of a non-exercising control group limit generalizability, though metabolic measurements were rigorous.

Source

Strength Exercise Improves Muscle Mass and Hepatic Insulin Sensitivity in Obese Youth

Gert‐Jan van der Heijden et al. · Medicine & Science in Sports & Exercise · 2010

DOI 10.1249/mss.0b013e3181df16d9

rct · n=12Cited 177×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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