[Kim Maengnyoung's Golf English Conversation] "The Difference Between Muscle Back and Cavity Back"

Muscle back (right) and cavity back are distinguished by looking at the back of the head.

"Muscle back and cavity back."

These are terms used to describe iron designs. A muscle back has a solid, flat back, while a cavity back is deeply hollowed out. The word "muscle" refers to its muscle-like appearance. The back face protrudes like a muscle, which is why it is called a muscle back. This is the traditional form of an iron head. The back is smooth, with a thin profile and a small overall size. It resembles a blade, which is why it is also known as a "blade iron" (also known as blades).

The weight is concentrated at the center of the head. The sweet spot is small and sensitive, requiring precise contact. Blades are considered players irons, designed for advanced golfers. They are suitable for professional golfers or skilled amateurs because they allow for greater control over spin and ball flight. The cavity back iron head was developed in the 1960s (Ping Eye cavity iron). The back of the head is hollowed out to distribute the center of gravity.

Overall, the head is thicker and wider compared to a muscle back. With a larger face, the center of gravity is lower, resulting in greater forgiveness. This makes them easier to control. They are easy to hit, and even if you hit the ground before the ball, the club is more forgiving (With a cavity back, the weight on the clubhead was moved to the edges and made them far more forgiving and easier to hit). Naturally, it is more difficult to execute precise shots like with a muscle back.

Golfer A: I want to buy some new irons. What is the difference between blade and cavity-back irons?

Golfer B: In a cavity-back iron, the weight of the head is distributed around the edges. This makes them more forgiving when you have a shot that is off-center.

Golfer A: So, those would be good for beginners. What about the blade irons?

Golfer B: Blade irons have the concentration of weight directly behind the center of the club face. If you like working the ball left and right, you might want to choose a blade.

Written and photographed by Kim Maengnyoung, golf columnist