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 elements of a shirt's design: type of seam stitching, type of fabric, and fit. Since fit is particular to each person's individual 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 the manner in which these seams are joined has a large role in how comfortable that shirt is. Simply put, you may not notice the seams of your shirt on a daily basis as you sit at your desk or live your life. However, running is the repetition of a very specific motion for long periods of time, and as your body and shirt bounce and rub against each other repeatedly thousands of times over again, seams can rub against skin to produce 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 was 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 like running shirts 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. One shirt, the Arc'teryx Motus Crew, used a variation of this seam stitch, the Merrow Stitch, which we found to be even softer and more comfortable than the rest.
Over Lock Seams
Over lock seams are far more common in traditional clothing manufacturing, but because they are higher profile, have the potential to rub a runner far more than flat lock 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 can be found a hanging tab of fabric where it was sewn, in stark contrast to the flatness of the flatlock. Only two shirts in this review used overlock seams — the Under Armour UA Tech and Russell Athletic Dri-Power Core Performance. Both of these shirts used over lock seams on the sides of the torso, where they don't rub much, with flat lock seams around the arms and shoulders for better comfort. Since this seam is far cheaper to sew in a factory, these are two of the most affordable shirts in this review.
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 literally no protrusion to rub at all. Only the Patagonia Windchaser used entirely taped seams, a large part of why we found it to be the most comfortable overall. The North Face Better Than Naked also employed taped seams, but only on the shoulders were the most rubbing takes place, and used more traditional flat lock seams everywhere else. The only downside to taped seams is that their life span might be shorter than sewn seams, as repeated abuse and washings have the ability to eventually cause the adhesive to de-laminate.
Types of Fabric
When it comes to comfort, the type of fabric used in the shirt is the second most influential aspect of a running shirt's design. All of the shirts in this review are made out of polyester, although a few of them are blends with other types of yarn. Below we describe the properties of each type of fabric.
The majority of the shirts tested and described here are made of 100% polyester. 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. That said, runners who run in very hot conditions, such as during the Western States 100 Endurance Race where daytime highs often approach 100 degrees, sometimes feel that polyester dries too quickly, and often opt for cotton clothing so that they stay wet and cool longer.
100% Recycled Polyester
The Patagonia Windchaser is the only shirt in this review advertised to be made of recycled polyester. For full disclosure, we receive no benefits or kickbacks of any nature from Patagonia, or any other company, for singling them out like this, but we have to give serious props where it is due. Environmental degradation such as chemical pollution abounds in our world today, and polyester is a synthetic derivative of oil that is neither sustainable nor biodegradable. We are happy that at least one company is making a small drop in this oceanic problem by using only 100% recycled polyester for their garment.
The Smartwool PhD Ultra Light running shirt is made with a blend of merino wool fibers and polyester in close to even ratios. The merino wool is natural and is capable of absorbing up to 30% of its weight in water. This means that it will dry slower than non-absorbent polyester, aiding with cooling through evaporation longer. It also has naturally anti-odor properties, stretches easily, and offers sun protection of UPF 30 or more. While Smartwool claims that its merino wool is very narrow in diameter and doesn't itch like traditional wool, we find it to be less slippery against the skin than 100% polyester.
The Nike Dri-FIT Knit uses a blend of polyester and nylon fibers in a nearly equal ratio. Nylon is another synthetic material that has a lot of the same properties as polyester. Nylon is the stronger of the two fibers, and also often feels softer to the touch. It is also a very stretchy fabric. On the other hand, it is capable of absorbing water, and so does not dry out as fast as polyester. This was evidenced in our drying speed test, where this was the slowest of all shirts to completely dry out.
Breathability vs. Drying Speed
By assessing each running 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 air flow 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 featured mesh paneling or very thin fabrics that allowed for air to easily transfer through them scored 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 — played a large role in a shirt's drying time. Wicking is the ability for 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 of 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. Water absorption (or retention) was also a critical component of how quickly a shirt was able to dry. Fibers like nylon and wool can absorb water, unlike polyester. However, different weaves of polyester have the ability to retain water by trapping the molecules in its matrix, and both situations led to slower drying times.
Of course, whether we are talking about breathability or drying time, what we are 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.
We like to think of features as the extra little add-ons that go a long ways toward differentiating shirts from each other, and also contributing to the effect of wearing the shirt. 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 are reflectivity, odor control, and UPF ratings. These are discussed below:
In order 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 for a running shirt, they add a sense of security for those who like to run in the dark. Look on manufacturer's 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 New Balance Ice 2.0 — which each featured five reflectors positioned on all four sides of the body.
Five of the 10 shirts included in this review purport to have some form of odor control technology working to keep them from stinking up a storm. Basically, when you sweat, microbial bacteria immediately begin working to break down fatty acids in your sweat, a process that can be blamed for the stink of your workout clothes. Making this worse, these bacteria find it very easy to bond to and hang out in synthetic clothing, which is why synthetics have long been known for their over-the-top smell retention. Wool is naturally anti-microbial, an advantage to the merino wool blend used in the Smartwool PhD Ultra Light. For synthetic fabrics, silver nanoparticles have become perhaps the most common way of providing odor control, as they effectively repel the micro bacteria that cause your funk. Polygiene, an applied treatment, is perhaps the most famous of these and is used on the Patagonia Windchaser. Another method of odor control is by adding odor-absorbing agents to a garment. The Under Armour UA Tech, Brooks Distance, and Russell Athletic Dri-Power Core Performance all contained some form of odor controlling agent, but that agent was not disclosed. As far as passing the smell test? We sniffed each of these shirts days after we last wore them, and to be honest they were not exactly odor free. We couldn't tell if they smelled better than they would have if no odor-controlling agent was present at all, so you be the judge.
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? Well, all clothing protects the wearer somewhat; it is estimated that 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 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.
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. The North Face Better Than Naked was our Top Pick specifically for this purpose. Other shirts that feature large amounts of mesh paneling to aid in air permeability are the Patagonia Windchaser and New Balance Ice 2.0. Worth noting is that in extremely hot temperatures, it can be advantageous to stay wet, and in these circumstances wearing an absorbent fabric, like cotton may serve you better than extremely fast-drying polyester.
For running in cool or cold weather, we most often choose to layer over the top with a windbreaker or running jacket. All of these shirts will work fine for this situation, but ones with a sleeker, more athletic fit will layer better than larger baggier options. Check out the Salomon Agile SS Tee, New Balance Ice 2.0, Brooks Distance, Nike Dri-FIT Knit, Smartwool PhD Ultra Light, The North Face Better Than Naked, or the Arc'teryx Motus Crew for slimmer, more athletic fits.
Ultra or Adventure Running
Ultra runs, or long adventure runs are usually accommodated 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 a ton of mesh on the back and shoulders will probably last a lot longer, as the repeated bouncing and jostling could quickly wear a hole in very light mesh. Of the selection in this review, we would avoid The North Face Better Than Naked and New Balance Ice 2.0 for running a lot with a vest on.
Hiking or Backpacking
Technical running shirts work great for hiking or backpacking 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. The only ones we would specifically avoid would again be The North Face Better Than Naked and the New Balance Ice 2.0.
Working Out at the Gym
Synthetic shirts such as these running shirts also work ideally for working out at the gym. Indeed, the two most affordable shirts in this review — the Russell Athletic Dri-Power Core Performance and the Under Armour UA Tech — are workout shirts that also work great for running. 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 other cold weather activity, we like having a breathable, slippery polyester t-shirt on as our base layer. Warmth layers worn over the top easily slide over these shirts 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. We think the Arc'teryx Motus Crew is the best shirt in this review for this purpose, which is why we gave it a Top Pick award. Other good ones are the Patagonia Windchaser, Smartwool PhD Ultra Light, the Brooks Distance, and the Under Armour UA Tech.
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. We hope this article has aided you in the search for your next shirt, and happy running!