Although running jackets may look similar, they function quite differently. Windbreakers, rain jackets and insulated models each serve a different purpose. These differences are due to the materials and construction, not the name. The membrane, its parameters and ventilation are key factors. In this article, I explain how to choose a running jacket and why a windbreaker is not always a suitable substitute for a rain jacket.
Types of Running Jackets
There are many running jackets on the market. They differ in color and cut, as well as purpose. A jacket is the outermost layer worn during a run and protects against wind, cold and possibly rain. Like most running clothing, running jackets are made of technical materials. There are two main types of running jackets. The lightest and cheapest option is the windbreaker. They primarily protect against wind and cold. They are thin, breathable and easy to pack. However, they are not rain jackets, even though they often resemble them.
The second main group is rain jackets. These jackets are made of a material integrated with a waterproof membrane. Their purpose is to protect against precipitation. They function differently than windbreakers. They are less breathable, but they keep water out. Depending on the parameters, there is always a trade-off between waterproofness and breathability.
The least common category is insulated jackets. These jackets are only suitable for frost and very low temperatures. In places with little snowfall and moderate temperatures in the winter, these jackets are impractical and will quickly lead to overheating. It is difficult to regulate body temperature in them.
When Does a Running Windbreaker Make Sense?
As the name suggests, a windbreaker jacket is designed to protect against the wind. They are typically made of a lightweight, technical fabric that blocks the wind to some extent, but is not waterproof. Such jackets’ fabric absorbs water quickly and allows it to pass through to the inside. Therefore, it is not a barrier against rain. However, they reduce the impact of the wind, thus reducing cooling during running. Windbreakers work well at lower temperatures without precipitation. Its biggest advantage is its low weight. Often weighing less than 100grams, it can easily fit in a pocket or waist belt.
Windbreakers are breathable. Excess heat and moisture escape quickly. This makes them ideal for intense running. However, this jacket is designed for dry conditions and variable winds, not precipitation.
Rain Jackets for Running: The Role of the Membrane
A rain jacket is made with a membrane. This membrane is a thin layer placed within the fabric. Its job is to keep water out. The membrane’s structure is porous. The pores in the membrane are small enough to prevent water droplets from passing through. At the same time, the pores are large enough for water vapor molecules to pass through.
Membranes are described by specific parameters. Most often, these are the water column and breathability. The water column indicates how long the fabric will resist rain. The higher the parameter, the longer the membrane will resist rain. Breathability determines how much water vapor can escape to the outside. This parameter determines the fabric’s water permeability. While these values are helpful for comparing jackets, they do not tell the whole story.
Mechanical ventilation is also very important. Underarm zippers and a looser fit improve thermal comfort. Without these features, even a good membrane will not be able to keep up with moisture wicking. Remember that during strenuous exercise, such as running, our body produces sweat, i.e., moisture. Combined with body temperature, this moisture will make a jacket with a membrane damp on the inside, even though it does not let water in from the outside. This is a natural phenomenon. Additionally, the higher the intensity, the more moisture the body produces. A jacket that works well during a gentle workout may fail during a strenuous run. A membrane only works under specific conditions. A “waterproof” jacket does not guarantee that you will stay “dry” underneath it while exercising.
Rain jackets are best suited for light workouts on windy and rainy days. At higher intensities or in higher temperatures, it is easy to overheat. This is the price you pay for real protection from the rain.
Warm Running Jackets: A Choice for Severe Winter Conditions
The last group of jackets is insulated. These are usually the least practical for running. Insulation retains heat close to the body, which is beneficial on cold days and during easy runs. However, at higher temperatures or during intense running, they quickly lead to overheating. The breathability of these jackets is also limited, which is beneficial in extremely cold conditions. At temperatures around 32°F (0°C), you will probably start to “boil” in this type of jacket. Additionally, sweat and moisture will remain under the jacket, reducing comfort.
Temperature regulation is also problematic. They are difficult to unzip or pack away while running. They do not adapt well to changes in pace or conditions. They work best on very cold days and before and after training.
