Icebreaker Cool-Lite Rush Review

This unique jacket is high on comfort and breathability but low on features that would enhance its standing as a running-specific layer.

Performance Comparison

Breathability

Hot or cold, windy or calm, track workout or long-slow run, running is a sweaty activity. We need a layer that can keep up with us, and breathability is one of the biggest limiting factors. The Rush is a much more complex jacket than some of its competitors. The inner material is a highly breathable, lightweight merino wool. Separated from this is an outer layer of wind-breaking nylon that is full of small holes. This separation and venting make for excellent airflow.

New for this year, this jacket now also has some awesome back vents, helping air escape one of the sweatiest areas while still keeping you protected from the elements. We love the way the merino feels and breathes, and with these new vents, you can really ramp it up in the Rush.

Weather Resistance

As we found time and time again in the testing process for this review, weather resistance and breathability often go head-to-head. It's hard to find a combination of materials and construction that can simultaneously keep out wind but also allow for air to flow. The Rush does both really well with a one-of-a-kind layout. With two separate layers that are detached from one another except at the seams, air can easily escape the wool layer and work its way out of the nylon. At the same time, the nylon stops the wind from coming in. It's genius, really. This jacket performs incredibly well in windy conditions, up there with any of the lightweight wind shells we tested.

As far as protection from precipitation goes, the Rush provides a decent amount of resistance, but it certainly isn't a rain jacket. During light rain, it can wick away moisture quickly enough, but we wouldn't recommend this jacket for hours of consistent rain.

The third weather factor to consider is the cold. While most of the jackets we tested are lightweight, non-insulated layers, the Rush is an interesting middle ground. While not nearly as warm as the insulated Arc'teryx Gaea, we did find this jacket to be a significant middle ground for cool mornings and evenings.

Comfort and Mobility

During months of hands-on testing for a variety of running-related products, including top-rated women's running shirts and hydration packs for running, we quickly learned that comfort is a performance factor. Beyond chafing and sore spots, comfort affects the level of enthusiasm and psyche you will have for your outing. The Cool-Lite Rush is hands-down one of the most comfortable jackets we reviewed. The inner merino wool layer is outrageously soft and luxurious, and has a bit of stretch that makes for a wonderful fit in the shoulders and back. Compared to the trash bag-like lightweight wind jackets we tried, we never wanted to take this jacket off and often found ourselves wearing it long after our workout had ended. The fit is both loose enough for activewear and form-fitting enough to earn style points.

Portability

Here at GearLab, we're a little bit weight crazy. We're known for counting ounces, putting everything we test on a scale, and debating weight versus performance. Running is a unique sport, however, in that it's much more about speed than some of the other activities we love. And because we're trying to move fast, weight and portability are even more important than normal. We don't want our gear to hold us back, which is why we looked at two similar qualities for this metric: weight and packability.

In the first of these, weight, we're afraid that the Cool-Lite Rush is behind many of its competitors. There are some heavier jackets in this review, too, but the majority of our favorite layers were a fraction of the weight. At 9.4 ounces for a size small, the Rush is a bit heavy for carrying around, even though it feels nice when you're wearing it. While it does pack down into its own pocket, something that helped boost its score in this category, it is definitely much bigger than many of its competitors.

Features

One of the first things we look for in a running jacket is visibility. Having reflective markings helps keep you safe from vehicles, though if you're strictly a trail runner, this may not be as important to you. The Rush has reflective markings in the front, along the zipper, but nothing on the back. Typically, the back is a better place for these markings to warn cars who are coming up behind you.

The Rush has two front zippered pockets. While useful, we would have preferred a chest pocket, where things bounce less, or a media port. Though not necessary, those are some of our favorite little details on some of the other contenders. Additionally, the Rush does not have a hood, which we think is more comfortable but less versatile. That said, it does have thumb loops in the extended merino sleeve, something we adore on those chilly morning starts.

Value

The Cool-Lite Rush is one of the most expensive jackets in this review. We assume that this is due to the luxurious merino wool interior, a material that is often associated with more expensive clothing. Only you can decide if the price point is truly worth it — all we know is that this jacket is super comfy and breathable, and we never wanted to take it off.

Conclusion

The Icebreaker Cool-Lite Rush is a uniquely comfortable and breathable layer. Though lacking in some of the fancy features of our award-winning items, it could easily suit the needs of any trail runner who cares more about comfort than ounces.