FFMI Calculator

FFMI is an alternative to body mass index which accounts for a person's muscle mass. The average male scores about 19 and it is hard to score above 25 without using steroids or other banned substances.

Mathematical Formulas

• Total Body Fat = Weight * (body fat % / 100)
• Lean Weight = Weight * (1 - (body fat % / 100)
• FFMI = (Lean Weight / 2.2)/ ((Feet * 12.0 + Inches) * 0.0254)²
• Adjusted FFMI = FFMI + ( 6.3 * (1.8 - (Feet * 12.0 + Inches) * 0.0254))

FFM by Percentile

FFMI Ranges for Men

FFMI Ranges for Women

Notable Athletes

Fat-free mass index in users and nonusers of anabolic-androgenic steroids is an excellent study which uses information from the pre-steroid era to establish a baseline on likely steroid usage among modern athletes and bodybuilders. The below table includes the performance of Mr. America winners from before the steroid era to some current athletes. Some sumo wrestlers have exceptionally high FFMI scores which can significantly exceed normal ranges.

Sources:

• Scientific studies
  • Fat-free mass index in users and nonusers of anabolic-androgenic steroids.
  • Body composition and isokinetic strength of professional Sumo wrestlers.
  • Body composition interpretation. Contributions of the fat-free mass index and the body fat mass index.
  • Contrasts in muscle and myofibers of elite male and female bodybuilders.
• Online resources
  • Reuters: Bonds weight gain used as steroid evidence by many
  • Xbodyconcepts: Steroids, Crossfit and the Crossfit Games: Who & How
  • Bodyrecomposition: Another Look at the Fat-Free Mass Index (FFMI): Part 2
  • Medium: Fitness, Part 1 — Aesthetic Physique
• Books
  • Game of Shadows: Barry Bonds, BALCO, and the Steroid Scandal that Rocked Professional Sports
  • Bases Loaded: The Inside Story of the Steroid Era in Baseball by the Central Figure in the Mitchell Report
  • Juiced: Wild Times, Rampant 'Roids, Smash Hits, and How Baseball Got Big
  • Vindicated: Big Names, Big Liars, and the Battle to Save Baseball

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