A Benefit of Being Heavier Is Being Strong: A Cross-Sectional Study in Young Adults
ten Hoor GA, Plasqui G, Schols AMWJ, Kok G
Evidence is still limited and needs further study
Summary
A cross-sectional study of 68 adults aged 18–30. Greater body size (weight and BMI) was associated with higher absolute maximal strength on combined leg press and chest press (BMI vs. maximal strength r=.49, p<.001). Body weight correlated strongly with fat-free mass (r=.70–.80), and fat-free mass in turn related to 1RM. In other words, heavier people are stronger not because of fat itself but because of the extra fat-free mass (muscle) that comes with a larger body. This concerns absolute strength, not strength relative to body weight.
Key findings
- 1
Larger body size (BMI) is associated with higher absolute maximal strength (r=.49, p<.001)
- 2
Higher body weight correlates strongly with fat-free mass (r=.70–.80), and that fat-free mass relates to 1RM
- 3
Heavier people are stronger because of the fat-free mass (muscle) gained with a larger body, not the fat itself
- 4
A cross-sectional study (n=68) cannot show causation; this is absolute strength, not weight-relative strength
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