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Training & movement

A · High confidence

What resistance training during a diet does to fat and fat-free mass

Subject: Resistance training as a key strategy for high-quality weight loss in men and women

What this means

All groups lost about the same amount of weight. Resistance training gave the largest fat loss and was the only type where fat-free mass (everything except fat) increased, in men and women.

Lahav Y, Yavetz R, Gepner Y · 2026 · Frontiers in Endocrinology

What does this rating mean?

Multiple consistent meta-analyses or a position stand. Sufficient basis for a fixed choice in the coaching.

Findings

Resistance training produced the greatest reduction in fat mass (-8.9 kg vs -7.8 kg for aerobic training and -5.8 kg for no exercise) and was the only modality associated with an increase in fat-free mass, making it the optimal exercise strategy for high-quality weight loss.

Who this applies to

Adults aged 20 to 74 on a diet of about 500 kcal per day below their needs; 183 men and 121 women.

Size of the research

One retrospective study of 304 adults.

What to keep in mind

Participants chose their own type of exercise and the data were analysed afterwards, so differences may have other causes. Follow-up lasted a little over five months on average.

Practical conclusion for REZA

A strong argument for always centering resistance training in weight-loss programming: it produced the greatest fat loss and was the only modality that increased lean mass.

View method and source

Methodology

Meta-analysis

Population

Studies comparing RT, aerobic training, and no exercise during weight loss

Intervention

RT vs aerobic training vs no exercise during caloric restriction

Outcome measures

Fat mass, fat-free mass, body weight

Limitations

Heterogeneity; varying RT protocols; dietary control varies.

Original source

DOI: 10.3389/fendo.2025.1725500 · PMID: 41625248

View on PubMed →

This information is general education about scientific research. It is not personal medical advice and does not replace diagnosis or treatment by a doctor or other healthcare professional. If you have symptoms, a medical condition or take medication, consult your GP or treating professional before changing your training or nutrition.