Oklahoma City took the top spot in the study that ranks towns based on factors such as the number of steak houses, pick-up trucks, motorcycles and home improvement stores per capita.
Cities can move up the list with a high percentage of "manly" characteristics, such as a higher population density of firefighters and police officers or successful sports teams. Cities with "unmanly" traits, such as a high number of nail salons or shopping boutiques, slid down the list.
The rankings included the top 50 U.S. cities by metropolitan population. Four of the bottom five cities on the list were from California, with San Diego earning the distinction of "America's Least Manly City."
The study might draw criticism for its limited definition of "manhood." San Francisco, long considered to be a central point for the gay rights movement, placed 49th on the list of 50 cities.
Combos compiled the rankings with the help of Bert Sperling , who engineers the annual "Best Places to Live" study.
The Combos brand is part of Mars Chocolate North America, based in Hackettstown, N.J.
"The results don't lie: the manliest place to be is the city they call 'OKC,' " Mars Chocolate general manager Craig Hall said in a statement. "From its stellar hoops team to its love of pick-up trucks, Oklahoma City exemplifies the best of being a man."
Some of the top manliest cities according to Combos are:
1. Oklahoma City
2. Columbia, S.C.
3. Memphis, Tenn.
4. Nashville, Tenn.
5. Birmingham, Ala.
7. St. Louis
8. Toledo, Ohio
10. Charlotte, N.C.
11. Louisville, Ky.
14. New Orleans
To read to full list, go to www.americasmanliestcities.com.