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Review Summary

When I find something that checks all of the boxes for its intended purpose, I tend to double down. That is exactly what I have done with the Reigning Champ Deltapeak™ training t-shirt. As a recreational runner regularly competing in half marathons as I train for the full, I’ve put this shirt through the absolute paces. The end result, me purchasing one for each day of the week. 

I’ve been incredibly happy with the overall cut and material of this training shirt. The performance tailoring provides for an incredible fit that sits close to the body yet features tons of mobility by way of semi-raglan sleeves, underarm gussets, and a nice subtle stretch in all directions. The advanced Deltapeak™ fabric is highly breathable, ultra lightweight, and soft on the skin to avoid any type of chafing over longer runs. The moisture wicking properties help keep the body dry by pulling sweat from the surface of the skin and passing it through the shirt for quick evaporation on the exterior. The quick drying properties help ensure the shirt is never adding weight through water/sweat retention which is a major plus. 

Anti-microbial properties keep the Deltapeak™ training shirt smelling new after each wash, even post hard runs with long stints in the hamper. The tight weave mesh maintains its perfect shape, keeps the body super cool, and also provides UV protection from the harsh rays of the sun. I’ve yet to find an all around better running shirt that melds high end performance, Canadian made quality, and a proper performance fit that is leaps ahead of all others.

Review Ratings


  • Deltapeak™ mesh moisture management fabric is highly breathable, moisture wicking, and won’t stick to the body when sweaty
  • Ultra lightweight which makes it a dream for hot weather endurance activities such as running
  • Smooth tight weave is soft on the skin, has a subtle stretch, and does not cause any unwanted chafing
  • Awesome Reigning Champ tailored performance fit that is not found in other offerings


  • Some minor snagging on interior of shirt when repeatedly coming in contact with rigid objects (zippers etc), however, this is easily avoidable
  • More expensive than big name brands, but you 100% get what you pay for
  • Color offerings are limited if you’re looking for variation

Reigning Champ Deltapeak 90 T-shirt

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Review Details

Reigning Champ Deltapeak T-Shirt Sizing

One of the factors that has converted me to adopting the Reigning Champ athletic line is no doubt the proper performance fit that is tailored for athletes. While I completely understand the need for most of the larger players in the space to construct their garments to fit various body types in order to hit a bottom line, I really prefer the more niche approach. The Reigning Champ Deltapeak™ training shirt is cut and sewn like many of the other offerings from the brand, slim through the body, decent length, and sleeves that follow your silhouette closely.

At 5’11” and roughly 165-170 pounds with a typical runner's build, I found the size large to fit my body type perfectly. The shirt is noted as having a ‘performance’ fit which is in fact more fitted than the original slim fitting t-shirts produced by Reigning Champ. When laying the large Deltapeak™ training shirt on top of the large lightweight t-shirt, it’s clear that the training shirt is more tapered throughout the body by roughly 1” and is shorter in length by about 1.5”. Sleeve length and shoulder width is nearly identical.

Reigning Champ has purposely nailed the difficult balance of slim fitting yet enough room for athletic movement. The Deltapeak™ material has a nice subtle stretch to it that allows for effortless flexibility in all directions no matter the activity. The 100% polyester does not have the same amount of pull and give as a shirt that contains elastin, but I will say there is plenty. I find the extra fitted nature of this shirt to be a welcome addition as it just feels all around better not having billowing material waving in the wind as I execute my runs. That being said, rest assured, this shirt is far from fitting like spandex. 

Signature underarm gussets and semi-raglan sleeves found on all Reigning Champ tops, provide another dimension of mobility. While I can’t speak to the effectiveness of these features as they pertain to the movements in other sports, I can say that while running, the lack of any type of restriction makes it seem as if you’re in a tank top. It’s really tough to beat these intricate details.

A big concern I always have with any new training shirt, especially one that fits close to the body, is whether I will experience any unwanted chafing. This can be common with many training shirts during runs exceeding 10 miles or with certain weather conditions. Luckily, the lighter weight and soft hand feel of the Deltapeak™ fabric has kept me free from any type of painful irritation on the chest and other portions of the body, a massive win (you know what I mean if you’ve experienced this issue).

Reigning Champ Deltapeak T-Shirt Construction

Deltapeak™ is a tightly woven synthetic mesh polyester constructed by Teijin Frontier Group based in Japan. This soft performance fabric features some impressive moisture management which helps pull sweat away from the skin and expels it through the shirt to quickly evaporate on the exterior. This is clearly evident on long hot runs where sweat begins to build up around the neck and chest. You’ll notice that the Deltapeak™ shirt avoids sticking to the body or feeling as if it’s becoming tacky and obstructive. Given the super thin nature of the material, sweat is not retained in the fiber of the shirt, keeping it very lightweight and relatively dry in comparison to many other alternative materials. This is probably one of the greatest and most noticeable strengths of Deltapeak™.

While my runs are generally done under the rays of the sun, the dense weave Deltapeak™ material does have high water repellency which is a plus when randomly caught in inclement weather. For those perfect weather days, this technical fabric also features UV protection to protect the torso and provide a real sharp farmers tan. An understated benefit of Deltapeak™ is the anti-microbial properties that are inherent in the polyester. It should come as no surprise that with repeated heavy use and high sweat excretion, some shirts begin to break down and become permanently less than desirable to the nose. That is far from the truth with Deltapeak™. Because these shirts tend to rapidly dry after use and are anti-microbial, they can sit in a hamper for some time before washing and still come out smelling brand new.

The soft handfeel and somewhat sheer characteristics of Deltapeak™ are what truly make this training shirt one of a kind. Just to get ahead of the question now, sheer does not equal transparent. When holding the Deltapeak™ shirt up in the light, brightness does indeed shine through the squares in the weave pattern. However, when wearing the shirt, regardless of color, you can not see through the material whatsoever. This is something I often wonder before purchasing a lightweight performance shirt and was happy for this fact.

With a material as thin and lightweight as Deltapeak™, it naturally raises the question of durability. I did run into one minor issue worth noting where a high friction area on the underside of the shirt was continually rubbing against the head/pull of an exposed zipper found on the side pocket of my shorts. Because running is a physical motion that repeatedly moves the hips back and forth, the edge of the zipper would slightly and slowly snag the fibers of the shirt. This unfortunately resulted in a slight worn patch on the shirt after a few months. While this wasn’t visibly noticeable on the outside, it was still a bummer to see. Once I caught the issue, I began running with the pocket zipper in the down position and the problem was completely solved. I imagine this would be less of an issue in just about all activities outside of endurance running.

Aside from this minor avoidable blemish, durability has been significantly greater than par. After somewhere in the range of 700 run miles over the span of 5 months with weekly machine washes, these shirts appear both functionally and visually as when I first purchased them. Loose threads are non-existent and the overall shape and fit has remained unchanged. I have confidence the investment into these shirts will continue to pay off for years to come.

The overall construction of each Deltapeak™ training shirt incorporates many of the same elements found across the complete line of Reigning Champ. You’ll find the iconic semi raglan sleeves and underarm gussets that aid in mobility and give an athletic appearance. Flatlock seams throughout the body provide comfort as well as extra security to keep all the cut and sewn pieces held in place. The ribbed collar expands and contracts wonderfully to allow for not only ease in pulling over the head, but also style by avoiding being stretched out.

Reigning Champ Deltapeak T-Shirt Style

Style may be lower on the weighted scale for some when it comes to training apparel, however, if this is of concern to you, then the Reigning Champ training shirt is an easy choice. I prefer a neutral understated color palette (IE: black) when it comes to my training kit with pops of color coming by way of my Nike running shoes or District Vision Sunglasses. The Deltapeak™ shirt is always available in black as an evergreen color with a handful of seasonal offerings coming every once in a while (teal and olive were both absolute must haves). 

With athletic gear essentially consisting of basics, it’s difficult to pull off a unique style. That being said, I feel this is where the proper performance fit of the Reigning Champ Deltapeak™ shirt really shines. An overly baggy kit isn’t the most aesthetically appealing option if you remotely care about appearance, let alone performance. When Reigning Champ does what they do best, that is, apply their Canadian engineering, design, and manufacturing methodologies with technical materials to something as simple as a training shirt, the result can only be a well fitting winner. Pair this with their 7” training shorts and you have a simple running kit perfectly suited for marathon training.

The flatlock seams that run along the top of the shoulder, across the semi raglan sleeves, and down the underside of the underarm gussets add a level of detail not typically found on your everyday athletic shirt. I tend to appreciate this over engineering both from a functional and design standpoint as it adds slight contrast and breaks up the lines on what would normally be a very basic silhouette. Will the solid block color Reigning Champ Deltapeak™ training shirt win you high cred style points, probably not. But will it keep you from looking like an average gym goer in an oversized baggy tee, absolutely.

Reigning Champ Deltapeak T-Shirt Value

While most of what I tend to review skews towards the higher end of the price scale with a very subjective value rating, the Reigning Champ Deltapeak™ training shirt has the functionality to justify the cost. At $75 per t-shirt, I wouldn’t say it’s an outright affordable purchase. But when considering the laundry list of functional benefits, it may be just what you’ve been looking for if you’re an active runner.

The performance cut paired with the semi raglan sleeves and underarm gussets is what immediately sold me on making an initial purchase. The incredibly lightweight nature of Deltapeak™, high anti-microbial properties, and lack of chafing is what then led me to add 4 more to the rotation. When it comes to endurance running, I tend to follow the rule of sticking with what works. There’s nothing worse than the all too common blisters, chafing, pain or discomfort when on a 2+ hour run. After rounds of trial and error, it’s only wise to go all in once a winner has been established. 

I’ve had my fair share of training shirts over the years ranging from all the big name players. They typically did not stand the test of time, often becoming stretched out around the collar and unpleasantly stinky from continuous use. Having logged roughly 35 run miles per week in the Reigning Champ Deltapeak™ training shirts for the past 5 months, I can confidently say that they appear poised to handle all that I can possibly throw at them.

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