Why Is There A Liner In Running Shorts

As a runner, I’ve always wondered why there is a liner in running shorts. It seems like such a small detail, but it plays an important role in enhancing comfort and preventing chafing during those long miles on the road or trail. Today, I’m going to dive deep into the world of running shorts and explore the purpose and benefits of that seemingly insignificant liner.

The Purpose of the Liner

The liner in running shorts serves multiple purposes, all aimed at providing runners with maximum comfort and support. One of the main functions of the liner is to provide a layer of protection between your skin and the fabric of the shorts. This helps to prevent chafing and irritation caused by the repetitive motion of running. Without the liner, the friction between your skin and the shorts could lead to painful rashes and blisters.

Another important role of the liner is to provide support to your sensitive areas. The liner acts as a mini compression short, holding everything in place and reducing excessive movement. This is particularly beneficial for male runners, as it helps to prevent discomfort and potential injury.

Additionally, the liner helps to wick away moisture from your body, keeping you dry and comfortable throughout your run. The material used in the liner is designed to efficiently absorb sweat and prevent it from accumulating, which could lead to discomfort and chafing.

The Construction of the Liner

Now that we understand the purpose of the liner, let’s take a closer look at its construction. The liner is typically made from a combination of moisture-wicking and breathable materials, such as nylon or polyester. These fabrics are chosen for their ability to quickly move sweat away from your body and allow for optimal airflow.

In terms of design, the liner is often constructed in a way that contours to the shape of your body, providing a snug and supportive fit. It is usually seamless or has flatlock stitching to minimize any potential irritation or rubbing against your skin.

When to Wear Running Shorts with Liners

Running shorts with liners are ideal for shorter to medium distance runs, especially when the weather is warm. They offer the perfect balance of comfort, support, and breathability. However, for longer runs or races, some runners prefer to wear separate compression shorts or underwear for added support and moisture-wicking properties.

Caring for Running Shorts with Liners

To prolong the life of your running shorts and their liners, it’s important to follow proper care instructions. Always check the garment’s label for specific guidelines, but in general, it’s recommended to wash them in cold water and air dry them to prevent any damage or shrinkage. Avoid using fabric softeners or harsh detergents, as they can affect the moisture-wicking properties of the materials.


The liner in running shorts may seem like a small detail, but its purpose and benefits are significant. It provides a layer of protection, support, and moisture-wicking properties that enhance comfort during runs. So next time you slip into your favorite pair of running shorts, take a moment to appreciate the thought and design that went into that tiny liner.