How much of the average body is muscle? July 11, 2020 by Pamela Landy Most men’s bodies are composed of about 40 percent muscle. Women’s bodies are 30 percent muscle. Related Answers How many candies of each color go into the average bag of M&M’s? Where did Our Bodies, Ourselves get its name? What was the racial breakdown of the U.S. population at the beginning of the 20th century? Where in Santayana’s works does the line “Those who cannot remember the past are condemned to repeat it” appear? How much skin covers the human body? How much of the body is made up of bones?