Having too much fat on your body makes your heart and lungs work worse when you're under stress, so you can't run or lift as well.
See the scientific wording
Excess body fat reduces cardiovascular endurance and power output under conditions of physical or psychological stress.
Contradicted by evidence
ObservationalOne low-scoring study contradicts this claim, though the evidence is not conclusive.
What the research says
1 study reviewedSupporting (0)
No supporting studies found yet
We'll keep looking as more research is published.
Contradicting (1)
Cross-Sectional StudyHuman
The study found that overweight COPD patients could walk farther and had stronger muscles than normal-weight patients, which is the opposite of what the claim says.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
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Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 contradicting study
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