Upper limit of fat-free mass in humans: A study on Japanese Sumo wrestlers
Kondo M, Abe T, Ikegawa S, Kawakami Y, Fukunaga T
Evidence is still limited and needs further study
Summary
A study comparing body composition of 37 professional Sumo wrestlers, 14 bodybuilders, and 26 untrained men. Sumo wrestlers had significantly greater fat-free mass than bodybuilders; six exceeded 100 kg of fat-free mass, with a maximum of 121.3 kg (height 186 cm, weight 181 kg, 33.0% body fat). Although Sumo wrestlers had higher body fat (26.1% vs. 10.9% in bodybuilders), their fat-free mass (muscle, bone, etc.) beneath the fat was greater. The 'heavy-looking' physique's strength comes not from fat but from an enormous amount of fat-free mass. The authors suggested a fat-free mass / stature ratio around 0.7 kg/cm may be an upper limit in humans.
Key findings
- 1
Sumo wrestlers' fat-free mass exceeded bodybuilders'; six surpassed 100 kg, with a maximum of 121.3 kg
- 2
Despite higher body fat (26.1% vs. 10.9%), Sumo wrestlers still had greater fat-free mass
- 3
The strength of a 'heavy-looking' Sumo body comes from massive fat-free mass (muscle, bone), not fat
- 4
A fat-free mass / stature ratio around 0.7 kg/cm was suggested as a possible human upper limit
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