Flank steak is a popular cut of meat that is known for its unique flavor and texture. But what exactly is muscle is flank steak? In this article, we will explore the different muscles that make up this delicious cut of beef.

The Anatomy of Flank Steak

Flank steak comes from the abdominal muscles of the cow, specifically the lower chest and abdominal area. These muscles are responsible for supporting the weight of the animal and play a vital role in its movement.

Rectus Abdominis Muscle

The rectus abdominis muscle is one of the primary muscles found in flank steak. It is a long, flat muscle that runs along the center of the abdomen and is commonly referred to as the “six-pack” muscle. This muscle is responsible for flexing and stabilizing the spine, as well as assisting with breathing.

Internal Oblique Muscle

The internal oblique muscle is another key component of flank steak. It runs diagonally across the abdomen and plays a crucial role in trunk rotation and lateral flexion (bending sideways). This muscle also helps to support the spine during movements such as lifting or twisting.

Transversus Abdominis Muscle

The transversus abdominis muscle is located deep within the abdomen and wraps around the torso like a corset. It provides stability to the spine and pelvis during movement, as well as assisting with breathing by compressing the lungs.

Cooking Flank Steak

Because flank steak comes from heavily used muscles, it can be tougher than other cuts of beef. However, when cooked correctly, it can be incredibly tender and flavorful.

One method for cooking flank steak involves marinating it overnight to help break down some of its tougher fibers. When grilling or broiling flank steak, it’s important to cook it quickly over high heat to prevent it from becoming too tough.

Another popular method is to slice the steak thinly against the grain, which helps to further break down any tough fibers and create a more tender texture.


In conclusion, flank steak is an incredibly flavorful cut of beef that comes from the abdominal muscles of the cow. The rectus abdominis, internal oblique, and transversus abdominis muscles all contribute to this delicious cut of meat. With the right cooking techniques, flank steak can be a delicious addition to any meal.