Arc’teryx Motus AR Bottom and Crew Base Layers Review

Arc’teryx instills their renowned quality into their Motus AR base layers. The long sleeve crew and bottom inductions into the line present excellent options for a variety of outdoor enthusiasts. These fall into Arc’teryx’s “AR” (All Round) category, which means they are designed for a number of different uses. One of those uses is obviously backpacking, so let’s take a look at why you might want to have these in your kit (even in the warmer months).

arc'teryx motus ar

The Motus AR Crew LS in maroon keeping me warm (left) in the snowy North Carolina mountains.

Arc’teryx Motus AR Base Layers At-a-Glance


  • MSRP: $79
  • Weight: 5.1 ounces
  • Fit: Trim, ankle-length

Crew LS

  • MSRP: $79
  • Weight: 5.5 ounces
  • Fit: Trim

Circumstance of Review

I’ve been testing both of these layers throughout the course of the Fall, Winter, and Spring across the Southeast. Both layers have been backpacking on a variety of trips where the temperature has dipped below freezing and conditions have gotten wet. I have also taken these layers on dozens of trail runs across the changing seasons. Through both of the pursuits I have used them for, I have layered up while shivering cold and taken things well past sweaty.

Arc’teryx Motus AR Bottom and Crew LS Base Layers Review


  • Phasic Technology Engineered polyester fabric is breathable, moisture-wicking, and quick-drying.
  • Merrow Stitch Seam Construction – Reduces seam size for a smoother, more comfortable next-to-skin feel.
  • Fair Trade Certified – Produced in a Fair Trade Certified facility. Fair Trade Certified program provides workers with additional funds to improve their livelihoods.
  • Zippered Thigh Pocket (Bottom) – Large enough to hold an iPhone 8+.
arc'teryx motus ar

Sweet sweet thigh pocket.


Both of these layers are excellent options for their wide umbrella of designated activities: moving around until you get hot when it’s cold outside. While backpacking in temperatures that never got above the 40s, I’ve consistently been able to wear both of these layers all day without getting too sweaty (and I’m a pretty big sweater). Additionally, I’ve had mostly positive experiences using these for chilly trail runs (30-40 range).

For backpacking specifically, these both handy to just toss in a pack and forget about unless needed. They have a pretty average weight, but I’d say provide a bit above average warmth. On chilly evenings the bottoms kept me from getting too chilly moving around camp, and downright warm in my 20-degree bag while the outside temperature flirted close to that limit.

Read next – Gear Wars: Merino Wool vs. Synthetic Base Layers.

The Lowdown on Each Piece

The Top

Overall, I had the most consistent positive experience with the Crew LS base layer. In fact, I never ran into an experience where it didn’t meet or exceed my expectation for its performance. I could wear it all day with a pack on without sweating too much even when things got sunny. Despite its slightly thicker (in a good way) texture, I was also regularly impressed by how quickly it would dry out.

My experiences trail running were also nothing but pleasant. As a person who regularly gets too warm in layers, this layer actually thermoregulated. I could maintain heat when I needed it, and never got too terribly sweaty when I didn’t. At the end of the day, it’s just really a solid top base layer.

The Bottom

My experiences with the leggings were similarly positive, though I did experience a bit more overheating than I did on top. To be fair, that’s exactly what I expected and what is the norm for me. My legs do a good job staying warm longer than my top does, so I don’t ever need quite as much to insulate them as I do for my top layer. So again, as far as thermoregulation goes, these bottoms do as well or better than any others I’ve experimented with.

The bottoms have one fantastic feature that the top doesn’t though: a pocket. This zippered thigh pocket is nothing short of perfectly convenient. It’s just low enough on the leg that it doesn’t get in the way but is still easily accessible. It is also large enough to fit a large smartphone, albeit with a little bit of a squeeze. Still, this feature made trail running without a vest super convenient.

I did have one issue with the bottoms that I didn’t with the top though. Within my first few uses of the bottoms, I managed to rip the seams at the ankle. The cuffs don’t fit tight, but they don’t stretch much, so even now after dozens of uses I still have to be a little careful slipping into them. The rip I created didn’t seem to affect the functionality of the leggings, but I figured it was still worth noting here that they are susceptible.

A little bit of seam rippage early on in my testing.

Arc’teryx Motus AR Pros

  • Excellent thermoregulation
  • Truly quick drying
  • Softer and more comfortable than most other similar base layers
  • Thigh pocket on the leggings is highly convenient, especially for trail running

Arc’teryx Motus AR Cons

  • Definitely not the cheapest option
  • Tight stitching on the ankle cuffs
  • No drawstring for the waist could be an issue for hikers experiencing dramatic weight loss while on the trail

Final Thoughts

arc'teryx motus ar

Base layered up in the Alabama wilderness.

At the end of the day, these are both top-tier base layers. They’re both pretty basic, but they both do their simple jobs rather impressively. However, is “the best” really that much better than what Wal-Mart has to offer? Is shelling out $160 bucks for this collection going to make your experience that much better than the $30 you could probably pay for the most basic option out there? It’s hard to say honestly. But, for hikers that want the best they can get, these Motus AR options are a serious contender.

Shop the Arc’teryx Motus AR Crew Top

Shop the Arc’teryx Motus AR Bottom

Similar Base Layers

Patagonia Capilene Midweight Crew Top

  • MSRP: $59
  • Weight: 6.2 ounces

Patagonia Capilene Midweight Bottoms

  • MSRP: $59
  • Weight: 5.8 ounces

REI Co-op Midweight Base Layer Top

  • MSRP: $49.95
  • Weight: 8.6 ounces

REI Co-op Midweight Base Layer Bottoms

  • MSRP: $49.95
  • Weight: 8.5 ounces (L, all other comparison item weights are M)

The Arc’teryx Motus AR base layers were donated for purpose of review.

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