In untrained young men, doing resistance training for eight weeks with consistent effort and workload leads to a reduction in body fat by about 5–8%, no matter how the exercises are grouped into sets.
Mechanism
Synthesis from 1 study
Lifting weights makes muscles bigger, and bigger muscles burn more calories even when you're not exercising — this extra calorie burn comes from fat stores, which is why body fat goes down even if you eat the same as before (10.3389/fphys.2023.1301535). It doesn't matter if you do heavy sets or...
Most probable mechanism
When untrained men lift weights, their muscles grow bigger and need more energy to maintain themselves, even when they're not exercising. This higher energy use burns more fat over time, which is why they lose body fat even if they don't change what they eat — this happens whether they do fewer heavy sets or more light ones, as long as the total work is the same (10.3389/fphys.2023.1301535).
Resistance exercise generates mechanical tension and metabolic stress in muscle fibers, activating mTOR signaling and increasing myofibrillar protein synthesis, leading to muscle hypertrophy (10.3389/fphys.2023.1301535).
Increased muscle mass raises basal metabolic rate because larger muscles require more energy to maintain at rest, increasing total daily energy expenditure (10.3389/fphys.2023.1301535).
The elevated energy demand from increased muscle mass creates a sustained energy deficit relative to intake, leading to mobilization and oxidation of stored triglycerides in adipose tissue (10.3389/fphys.2023.1301535).
Evidence from Studies
Supporting (1)
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Effect of resistance training programs differing in set structure on muscular hypertrophy and performance in untrained young men
Contradicting (0)
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Gold Standard Evidence Needed
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