Smartwool Merino Sport Ultra Light Hoody - Women's Review

The Smartwool Merino Sport Ultra Light is a comfortable and breathable jacket with excellent features to suit all your running needs. We love the coziness of its merino interior and, most importantly, how the comfort doesn't compromise weather protection. If you want one versatile jacket to clothe you throughout all of your runs, this piece is our top choice for you.

Performance Comparison

What better place to show off one of our favorite running jackets than the beautiful Eastern Sierra?

Photo: Lauren DeLaunay

Breathability

As opposed to wind layers, which are often used in various activities (some more stationery than others), running jackets need to keep up with the high output. No matter how speedy of a runner you are, you're bound to work up a sweat. We tested breathability by running up and down hills in a wide range of climates to see how each layer compared to its competitors.

One thing we know about wind-resistant materials is that they don't usually breathe very well. Smartwool worked around this by including panels of wool and open vents to allow for excellent airflow. The upper back of the Merino Sport has a thin wool panel surrounded by two-inch open vents along with the shoulder blades and on top of the shoulders for air to flow. Merino wool panels also extend from under the arms to halfway down the sides. This stretchy wool material is extremely thin with small holes, and we found it incredibly effective at helping us manage our body temperature. The only negative we found is that it hangs onto body odor fairly aggressively. If you're anything like us, this is a nonissue. If this bothers you, beware.

The variation in textiles makes this a weather-resistant and comfortable running jacket.

Photo: Ally Meller

Many of the jackets we've tested over the years manage their weight by employing only one material throughout. The Merino Sport is minutely heavier than some of its competitors, but the return is in superior breathability, which we've deemed the single most crucial factor in running jacket success. If you are looking for a jacket in which to work up a serious sweat, the Smartwool Merino Sport is going to be your best bet.

The rear vents are a nice feature that blends breathability with weather protection.

Photo: Ally Meller

Weather Resistance

Because we generally prefer to run with as few layers as possible, running jackets are only necessary when the weather is less than ideal. Whether you're heading out in a sprinkle, a wind storm, or just on a cold day, your running jacket needs to protect you from whatever elements may arise.

The Merino Sport is a thin yet weather-resistant layer that is not ideal for true winter running. However, it does provide some warmth. The wool panels are very thin and do not offer much insulation, so we find this jacket is best for crisp spring or fall days or whenever the wind and rain start to pick up. This time around, we tested it throughout spring in the unpredictable drizzle of Seattle. This jacket is the perfect jacket for a moderate yet volatile climate. While some runners can't stand running in a hood, we like that the Merino Sport has this option. The hood also features merino wool paneling and is snug yet stretchy, making for a great running fit.

How do you test for rain protection in the desert? However you do it, the Merino Sport passes the test.

Photo: Lauren DeLaunay

This jacket performs as well as any other in the wind protection metric, and it repels water with ease. Our testing team loves the elastic wrist openings, which help keep the elements out and our fingers in if that's how we are choosing to run. Our hose-down test helped us simulate rain in a more controlled fashion, and the Merino Sport excelled. While it's not a "waterproof" jacket, per se, it does keep out a lot of moisture, and we'd happily take it out in light rain.

Maximum sprinkle repellence during the unpredictable PNW spring.

Photo: Ally Meller

Comfort and Mobility

Running is challenging enough — you don't need to make it any harder by stifling your movements with uncomfortable clothing that chafes, rides up, or restricts your movement. In this category, we evaluate each jacket's materials, cut, style, and mobility to see how they hold up in the most extreme circumstances.

The Smartwool Merino Sport Ultra Light is one of the most comfortable jackets we tested. While most of the jackets in this review feature one continuous material, the Merino Sport has two. The majority of this model is made of soft, smooth polyester. This fabric does not stretch but feels nice and slick but somehow gentle against the skin. Under the arms, along the back, and in the hood, this jacket hosts merino wool panels that are super luxurious; we love this stretchy, breathable feature. The softest parts of the jacket are typically the parts that come in contact with the skin, which only adds to the assumed coziness of this ultra-mobile wardrobe piece.

We love the comfy hood of the Merino Sport running jacket.

Photo: Lauren DeLaunay

The fit is spot-on, and though the polyester parts of the jacket don't stretch, the thoughtfully-placed merino panels do, providing an enhanced range of motion that the simpler models in this test don't have. For those who like running in a hood, it fits perfectly. The hood has an elastic interior that makes it delightfully snug without being constricting or too baggy in the wind.

We have found our first-ever hood that we actually enjoy running in.

Photo: Ally Meller

Portability

Two things make up each jacket's portability score: weight and packability. We know that conditions can change in the blink of an eye, so our testing team awarded higher points to jackets that pack up into their own pockets while keeping their weights low. Luckily while we were testing, we encountered our fair share of inclement weather. We were able to test every jackets' packability and ease of travel while out in the field.

We were pleased to find that the Merino Sport didn't compromise weight with its wealth of great features and materials. Despite its merino interior and hood, this jacket in size small weighs 4.8 ounces. This is definitely on the lower end, especially when you consider how weather-resistant this jacket is. Some of the other jackets we tested offered the same amount of protection from the elements but weighed almost double. For this reason, this particular jacket scored great marks in the portability category. The Merino Sport folds into its own right-hand pocket quickly and easily, a feature that adds significantly to its versatility. We happily bring this jacket along on hikes, bike rides, or mountain climbs because of how convenient it is to stow away.

Hidden in the right hand pocket is this jacket's ability to fold itself up.

Photo: Lauren DeLaunay

Features

What differentiates a "running jacket" from a "wind jacket," you ask? A few key features are marketed directly to runners, and our review team awarded high marks for jackets that include any or all of these features.

One of the main safety features that we want in an ideal running jacket is visibility. For running in urban environments, reflective logos are essential for being spotted by oncoming vehicles, especially at night. The Merino Sport has great reflectivity on the logos, and small slivery bits are woven throughout. The back is covered with sparkly reflective markings that are easy to dismiss during the day but light up when placed in direct light, such as those of car headlights.

The Merino Sport was an awesome choice for this brisk spring morning in Bishop, California.

Photo: Lauren DeLaunay

This jacket features two hand pockets, and the hood is great for running in inclement weather. We find the fit to be perfectly suited to keeping out rain and wind. We love the stretchy wrist openings that help keep out the elements as well. One of our favorite details is the headphone hole. The chest pocket has a small hole for slipping headphone cables through; we love keeping the cable tucked away and feel this is a great little detail for those of us that haven't upgraded to Bluetooth yet.

Value

The Merino Sport Ultra Light is reasonably priced and right in the middle of the products in this review. Our testing team agrees unanimously that this jacket is a worthy investment with an abundance of features, great comfort, and ideal breathability.

Conclusion

The Smartwool Merino Sport Ultra Light Hoody is an obvious choice for our Editors' Choice Award. Its merino panels ensure it's uniquely breathable and comfortable, and its lightweight hood and reflective back make it one of the most balanced jackets in this review. A reasonable price tag makes it an excellent investment that'll get you ready for any adventure. Once you try this jacket for yourself, you'll fall in love with it, just like we did.

This is definitely one of our favorite jackets.

Photo: Ally Meller