Compared to a lot of the outdoor gear we review on this site, choosing a running shirt is relatively easy. All of the shirts in this review are comfortable, fit great, do an effective job of keeping one cool while working hard, and have appropriate running-related features. In short, we don't think you can go wrong with any of these selections, and in order to determine which ones are the best, we had to pay very close attention to the subtle details. We were very nitpicky in our assessments, which might make it seem like some shirts are less worthy, which they aren't! This buying advice article is meant to shed more light on those subtle differences, including fabric types, seam sewing, breathability, and features. At the end, we discuss which shirts we believe are the best for specific purposes.
Like any piece of clothing, comfort is ultimately the most important thing to consider when buying a running shirt. During our extensive field testing, combined with a close study of each shirt, we determined that comfort is largely a product of three design elements: type of seam stitching, type of fabric, and fit. Stretch is a factor that plays into all of these elements of comfort as well. Since fit is particular to each person's body shape, we will leave it up to you to determine the best fitting shirt for your needs but will discuss the other two factors below.
Types of Seam Stitching
A shirt is made of many different shapes of fabric, all sewn together to produce a single garment. Where the smaller pieces join each other, you will find a seam, and how these seams are joined has a significant role in how comfortable that shirt is overall. Simply put, you may not notice the seams of your shirt daily as you sit at your desk or drive your car. However, running is the repetition of a very specific motion for long periods, and as your body and shirt bounce and rub against each other repeatedly thousands of times over again, seams can rub against the skin, producing irritation. So while the type of stitching in your work shirt may not be an important consideration, it should be of primary consideration for a running shirt. Below we describe the three main types of stitching we encountered in this review and the pros and cons of each.Flat Lock Seams
We start with this type of seam because it is by far the most common in the shirts we reviewed. Flatlock seams are where two pieces of fabric abut against each other and are then sewn together flat, without overlap. This is the most common type of seam sewing for outdoor clothing because it is among the most low-profile, leaving less material for rubbing. We found that the location and number of these seams also affected their comfort level. For instance, seams that ran across the back of the shoulders were particularly noticeable while running, whereas seams on the side of the torso tended to hang loose and weren't very noticeable at all. Gusseting these particularly problematic areas seems to have caught on with the more comfort-oriented shirt designers.
Overlock seams are far more common in traditional clothing manufacturing, but because they are higher profile, they have the potential to irritate or chafe more than flatlock seams. These are seams where the two pieces of fabric abut each other and are folded together, then sewn. On the outside, the seam looks nice with no stitching visible, whereas on the inside there is a hanging tab of fabric where it was sewn, in stark contrast to the flatness of the flatlock.
Taped seams are seams where an adhesive application is used to glue, or tape, the seam together, and no stitching at all is present. These seams are far and away the most comfortable against the skin, especially when running because there is no protrusion to rub at all. It is worth mentioning that while more comfortable, taped seams are also more delicate.
Beyond the type of seam stitching used, we noticed over time and lots of days testing that the type of thread used to stitch the seams together also varies from shirt to shirt. Additionally, the direction of the stitch "grain" is also important. Arc'teryx, for example, used such a tight stitch on their merrow stitching on the Cormac Crew that the seams are practically unnoticeable.
Types of Fabric
When it comes to comfort, the type of fabric used is the second most influential aspect of a running shirt's design. Most of the shirts in this review are made out of polyester, although a few of them are blends with other types of yarn such as nylon and lyocell. The Black Diamond Rhythm Tee is the lone shirt in this review made of a merino wool blend instead of polyester. Below we describe the properties of each type of fabric.Polyester
The majority of the shirts tested and described here are made primarily of polyester and blended with a form of spandex. Polyester is a synthetic chemical compound derived from oil and is not considered a natural fiber. It is very durable and easily retains its shape, making it a good choice for outdoor clothing. It typically has a smooth, slippery texture and can be formed into an almost unlimited variety of fiber thicknesses and weaves. Polyester is also non-absorbent, meaning it will not absorb water or sweat, so it is extremely fast drying. Being able to dry very quickly greatly aids in the ability of polyester fabrics to cool you down quickly when you become sweaty and are also valued for cold weather activities because they will not keep you wet for long.
While we have used shirts made from merino wool in the past with no issue, sometimes we find them to be a bit too itchy for our skin and they tend to disintegrate after a thousand miles of running. That said, there are some wool/synthetic blends that are more durable and have no itch. Comfort is a top priority, so keep this in mind when trying alternative fabrics. Personal skin sensitivity can make a large difference in fabric feel. There are upsides to merino, such as it being a natural, wicking fiber that insulates when wet as well as naturally protecting against odor.
Breathability vs. Drying Speed
By assessing each shirt for both breathability and drying time, it may seem as if we are grading twice for the same thing. However, while both of these metrics are pertinent to how well a shirt keeps you dry and cool, we feel they are like two sides of a coin.
Breathability refers to the ability of a shirt to efficiently allow for airflow through the fabric of the shirt so that sweat can remain in vapor form while passing from the inside to the outside air. Shirts that feature mesh paneling, or very thin fabrics that allow for air to easily transfer through, score higher in this metric.
Drying Speed, on the other hand, was measured in a controlled environment by comparing all the shirts, dripping wet, to each other. Two factors — wicking and water absorption — play a large role in a shirt's drying time. Wicking is the ability of a fiber to move sweat from the inside, through the shirt, to the outside where it can dry quickly, as it is exposed to wind and sunlight. This can happen due to differences in size and shape of fibers on the inside vs. outside of the shirt, or mechanically by fibers that are capable of absorbing water on the inside, where it can be pulled through the fiber by the evaporative action on the outside. Some fibers have natural wicking properties, like merino wool, while others use weaves to help promote wicking. Water absorption (or retention) is also a critical component of how quickly a shirt can dry. Fibers like nylon and wool can absorb water, unlike polyester. However, different weaves of polyester can retain water by trapping the molecules in their matrix, and both situations lead to slower drying times.
Of course, whether we use the terms "breathability" or "drying time", what we are really talking about is how effective a shirt is in keeping you cool. The faster the evaporation is taking place, the greater the cooling effect, but for a shorter period.
Features and Versatility
We like to think of features as the little extra add-ons that go a long way toward differentiating shirts from each other, and also contribute to the effect of wearing the shirt. Features primarily dictate the versatility of a shirt, in addition to fabric durability. When we talk about hardshell jackets, the number and type of features can be literally endless. But since we are talking about running shirts, there are only a few things that can reasonably be done to boost the value of the shirt without compromising its function. The three main features present in these shirts that help boost versatility are reflectivity, odor control, and UPF ratings. These are discussed below:
To increase a runner's visibility at night, most of the running shirts described here include reflective tabs or logos. When the headlights of a car hit these reflectors, they light up bright white, not unlike an animal's eyes when you shine a headlamp at them in the dark. While these reflectors are not strictly necessary, they add a sense of security for those who like to run in the dark. Look on manufacturers' websites, and you will often come across the descriptive term "360-degree reflectivity." However, we found this to be true for only two shirts — the Arc'teryx Motus Crew and the Baleaf Quick Dry — which each feature reflectors positioned on all four sides of the body.
Most of the shirts we tested either have natural odor protection (like merino fabrics) or some sort of proprietary odor control additive in the fabric. These all worked fairly well during our testing, but the natural, merino wool found in the Black Diamond Rhythm Tee was the best. If you remember polyester shirts from the past, they would hold onto odor to the point where it almost couldn't be washed out. While some of the shirts tested retained odor more than others, we suspect that many of these odor protection additives effectively help with odor.UPF Ratings
One feature that some shirts have is a UPF rating. UPF stands for Ultra-violet Protection Factor and is a rating comparable to the SPF ratings of sunscreen. Some manufacturers use special fabrics or dyes that boost a product's UPF. For instance, if a shirt has a UPF rating of 30, that means that only 1/30th of the ultra-violet light rays are getting through to hit your skin. But what about the shirts with no rating? All clothing protects the wearer somewhat; it is estimated that the average is between 8-15 UPF. However, a clothing product is not allowed to advertise its UPF rating unless it is measured at 15 or above, so those products with a rating have been specially designed to give you extra protection. The Cormac Crew is the highest-rated shirt in our review with UPF 50+.
The Decision Making Process
Trying to decide between all of the various running shirts available today can be made easier if you ask yourself a few pertinent questions to help narrow down the field. The most important question is probably: What do I intend to use this shirt for? Below we make recommendations for certain uses, so this can help you narrow down the field a lot. After that, we recommend looking at individual reviews to glean more information about the performance of a particular shirt. It is here that small preferences, such as features or fit, can help you decide between the last few remaining possibilities.
All of these shirts are designed to be worn while running, so if you want a running shirt, you are in the right place. We recommend you check out our top scorers.Hot Weather
For running in warm or hot weather, you will likely want the shirt that scores the best for breathability and drying time, as these factors help you cool down the quickest through evaporation of sweat. A shirt that features large amounts of mesh paneling to aid in air permeability is a great choice.
Ultra or Adventure Running
Ultra runs, or long adventure runs are usually accompanied by wearing a running vest or light pack to carry extra food, water, and essentials like rain gear. All of these shirts will work fine for long runs, but ones that don't have mesh on the back and shoulders will probably last a lot longer, as the repeated bouncing and jostling could quickly wear through light mesh. Fit is also critical for a long enduring effort. If there is any discomfort or chafing on a shorter run, it will only be exacerbated with greater distance, increased sweat, and the changing weight of a full hydration pack waning to empty between aid stations. The Arc'teryx Cormac Crew has the added benefit of a UPF 50+ rating, so it is great for all-day adventures.
Hiking or Backpacking
Technical running shirts work great for hiking, backpacking, or climbing as well! We often wear them in this capacity, and once again only caution against wearing a pack for too long in conjunction with a shirt made mostly of mesh that might not be able to withstand the abuse. For long thru-hikes like the AT or PCT, where stench can become a real issue, looking for something with Merino wool can help remediate that.
Working Out at the Gym
Synthetic shirts such as these running shirts are also ideal for working out at the gym. Indeed, some of the most affordable shirts in our review handle the sweat and intensity of gym workouts very effectively. While any of the shirts here will work great in the gym, you may not want to spend a lot of money simply for a workout shirt. For that reason, we would probably recommend the shirts that are on the more affordable end of the spectrum.
As a Base Layer
When skiing, ice climbing, or taking part in any cold-weather activity, we like having a breathable, durable t-shirt on as our base layer. The polyester weave of the Cormac Crew allowed warmer layers worn over the top to easily slide on without bunching. Durability and a sleek, athletic fit are the two main attributes to covet if planning to wear your running shirt as a base layer. The Rhythm Tee offers warmth and comfort as a base layer while wicking away sweat during nordic skis and ski tours. The benefits of merino wool and the durability of the nylon core make the Rhythm Tee the best shirt in this review for this purpose.
In this article, we have tried to present more in-depth descriptions of the attributes that make up the best running shirts. Of course, you can find tons more information on any of the topics covered above by searching the internet. But, we hope this article has aided you in the search for your next shirt, and happy running!