Research

Energy balance

Sustained moderate-intensity aerobic exercise combined with constant energy intake induces significant fat mass loss while completely preserving fat-free mass.

To lose fat without losing muscle, you must exercise moderately (around 50-55% of your max effort) for about 93 days, burning roughly 1,000 kcal daily through exercise, while eating exactly enough to maintain your current weight. Do not restrict calories; let the exercise create the deficit. This preserves your lean mass while stripping fat.

GoodSupportsHIGH confidence
Mean body weight loss was 5.0 kg (SEM = 0.6) (p < 0.001) and it was entirely accounted for by the loss of fat mass (p < 0.001). Fat-free mass was unchanged.
Claude Bouchard et al. · Obesity Research · 1994

Why this rating

High-quality controlled inpatient study with identical twins, though limited sample size (n=14).

Source

The Response to Exercise with Constant Energy Intake in Identical Twins

Claude Bouchard et al. · Obesity Research · 1994

DOI 10.1002/j.1550-8528.1994.tb00087.x

rct · n=14Cited 320×
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DOI resolved against Crossref · corpus check 2026-06-10

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