What Is The Strongest Muscle In Your Body?

What is the strongest human muscle? Is it your biceps, quadriceps or could it be your gluteus maximus? You might be surprised to learn that it’s none of the above. Though it depends on what your definition of “strongest” means.

If you by strongest you mean “ability to exert a force on an external object”, then a human’s strongest muscle is his or her ‘masseter’ muscle. The masseter muscle is a thick muscle in the cheek and is located at the back of the jaw. It’s responsible for opening and closing your jaw during chewing. It is the muscle that can generate the largest externally measurable force attributable to the action of a specific muscle. Its strength is the result of incredibly densely packed muscle fibers combined with being attached to a short-armed lever. It can close the teeth with a force as great as 55 pounds (25 kilograms) on the incisors or 200 pounds (91 kilograms) on the molars. Guinness Book of Records lists the strongest bite recorded at 975 lb for 2 seconds. That’s more than six times the normal biting strength of a human.

Now if you take ‘strongest’ to mean ‘does the most work’, the heart lies claim to that. The heart performs the largest amount of physical work in the course of a human’s life. The power output of the human heart range is estimated to be between 1 to 5 watts. Compared to the power output of other muscles, it’s much less. For example, the quadriceps can produce over 100 watts, but only for a few minutes, then it fatigues. The heart does its work continuously over an entire lifetime without pause, and hence ‘outworks’ every other muscle.

Bonus fact: Your smallest muscle is just one millimeter long and is inside your middle ear. It job is to support one of the tiny bones inside the ear, called the stirrup.

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