Merrell Agility Peak 5 review

We believe the Merrell Agility Peak 5 is a solid pick for:

• Heel strikers looking for a stable, all-terrain trail running shoe.
• Runners in need of a shoe that excels in muddy or snowy conditions.
• Those who desire a trail shoe that offers a great mix of durability, stability, and effective cornering.

Although the Merrell Agility Peak 5 is highly versatile, in our view it's not the ideal choice for those who primarily run on smooth paths or fire roads. For such terrains, other shoes like the Merrell Nova 3 or the Saucony Peregrine 13 might be better suited.

Additionally, it's not our top pick for forefoot or midfoot strikers due to its significant heel-to-toe drop. If you use one of these running techniques, we recommend opting for the Hoka Speedgoat 5 instead.

In the heel, we measured a generous amount of foam, with the stack height reaching an impressive 39.2 mm.

This instantly makes the shoe a fantastic choice for every heel striker, ensuring ample protection against sharp rocks. This is particularly beneficial because the shoe includes a rock plate, but only in the midfoot and forefoot areas.

Shifting to the forefoot, we found it thinner than expected, at just 25.8 mm. However, it's still thicker than the average shoe.

We believe that the Agility Peak 5 is well-suited for ultra races and long endurance sessions, even for midfoot and forefoot strikers.

Also, there's a blue rock plate underneath the foam to protect the feet in this thinner area.

Our tests showed a huge 13.4-mm offset, which is a major difference from the 6-mm drop Merrell advertises. Why?

Well, we strictly adhere to World Athletics guidelines for measuring every shoe. It's likely that Merrell takes their measurements at undisclosed spots, leading to the differences we observe.

Talking about cushioning, let's look at the midsole. The Merrell Agility Peak 5 uses FloatPro foam. This is an improved EVA-based material that provides a balanced ride.

Our durometer test confirmed this, showing a 22.0 HA rating. It's neither too soft nor too firm, which in our opinion, is great for trail running.

We can imagine many adventurers taking the Agility Peak 5 into very cold mountain temperatures, so this test is quite interesting. We freeze the shoe for 20 minutes and then re-test it to see how much it changes.

We discovered that the shoe barely changed, now measuring 24.6 HA.

That's just a 12% change, which is practically imperceptible and an amazing result for an EVA foam. These foams typically underperform in cold temperatures.

The insole is a bit thicker than the average, measuring 6.0 mm in our lab. This contributes to the overall cushioned feel of the shoe.

The toebox of the Merrell Agility Peak 5 is clearly designed for a performance fit. This helps when taking corners and provides a confident feel on the most technical terrain.

However, those with wide feet should be aware that this shoe doesn't offer much room inside. In our lab, the widest part of the toebox measured only 96.6 mm.

The toe area of the shoe receives the same treatment. At 74.8 mm, it tapers significantly and doesn't leave much room for toe splay.

Regarding stability, this Merrell performs well for a 40-mm shoe. Naturally, you can't expect it to be as hyper-stable as a lower-profile shoe, but we felt truly confident with it.

However, the Agility Peak series isn't designed for those seeking top-level stability. The name "Agility" suggests the shoe is meant to be agile, perfect for sharp turns. This implies that the shoe won't be extremely wide, but rather the opposite.

Even with the outsole cutouts designed to make it less rigid, we still gave the Agility Peak a 5/5 rating in our torsional rigidity test. This rigidity tries to compensate the lack of width of the shoe, although a bit more flexibility would be beneficial for cornering.

The heel counter is also stiff, and we rated it 4/5.

We believe this approach is spot on, as it keeps the heel secure and enhances the ride for heel strikers. In our opinion, those who strike with their heel are the ideal type of runner for the Agility Peak 5, especially because of the massive heel-to-toe drop.

As we mentioned earlier in this review, since the shoe is designed for "agility," it doesn't follow the currently popular maximalist, wide approach.

Instead, it takes the opposite direction, aiming for a nimble experience. This results in an average forefoot platform width of 111.8 mm.

The heel is a bit wider compared to the average trail shoe at 93.0 mm, which makes sense.

Again, as we said before, this shoe is mostly designed for heel strikers. This design ensures stability in the rearfoot and also helps during descents.

Earlier, we noticed that the shoe was very rigid when we tried twisting it. Now, it's time for our second flexibility test. Here, we're looking to see how flexible it is longitudinally.

Indeed, we found it stiffer than average, confirming our previous observations. We had to apply at least 36.6N of force to bend the shoe to a 90-degree angle.

We conducted the 20-minute freezing test again to assess the shoe's stiffness in cold winter conditions. Following the test, it required 45.5N of force from our arm to bend the shoe.

That's a 24.6% increase in stiffness, which, based on our extensive experience, will be noticeable to some runners but will likely go unnoticed by most.

This Merrell slightly exceeds the 10-oz benchmark at 10.2 oz (289g).

While the shoe doesn't feel extremely heavy, it could definitely benefit from shedding 0.5 to 1 oz. With today's technology, this reduction should be achievable.

As we mentioned before, this shoe is designed for technical terrain and wild adventures, so it needs a rugged and durable upper. Typically, this reduces airflow, but Merrell managed to achieve a decent balance, so we gave the shoe a 3/5 rating for airflow after our smoke test.

A 3/5 rating might seem worse than 5/5, but that's not necessarily true here. It all depends on what we're looking for.

In a trail shoe like this one, we wanted a balance that keeps it comfortable in winter while still being somewhat airy in summer. It won't be perfect in extreme temperatures, but it does a decent job across the whole spectrum.

A simple light test really showed us the truth about the airflow. Merrell focused on the toebox for ventilation, but made the midfoot really structured for better stability, so we shouldn't expect much airflow there.

Next, we used our microscope and found a dense engineered mesh that looks very durable. We'll discuss this more after our next test, which will really challenge the upper.

Finally, we thoroughly examined the cut upper.

We noticed that Merrell skipped any inner layer in the toebox for extra protection, which significantly improved airflow.

Like we mentioned earlier, the toebox has a single layer of breathable mesh, so we were curious about how it would do in our Dremel test.

Luckily, Merrell added protective layers to crucial areas of the shoe, and it turns out our test spot was one of them. So, it scored a perfect 5/5 in our test.

Of course, the results might have been different in another part of the toebox, but we test the exact same spot on every shoe, using the same force and RPM, to keep our tests consistent and fair.

The heel padding area felt really cozy when we checked it out, and often, that's not a good sign regarding durability.

As expected, it scored a mere 2/5 in our Dremel test, which is disappointing. Although this might not be an issue for most people over time, it's still a drawback worth noting.

We flipped the shoe over to examine the outsole, a crucial component of any trail running shoe. We discovered what we think is the best rubber for trail running as of today: Vibram Megagrip.

First, in terms of durability, we measured the hardness and found it to be 85.1 HC, which is pretty standard.

We tested the shoe in the trails and were impressed by its outstanding grip. However, we also look for durability, especially when running over tough terrain that crush the rubber. That's why we fired up the Dremel one last time!

After the Dremel worked its magic, we measured a 0.7-mm indentation in the upper. This is a fantastic result, promising a solid lifespan for the shoe.

The outsole is thinner than what we usually see in trail running shoes, at only 1.4 mm, but there are two reasons for this. First, the lugs are long, which we'll discuss more later in this review. Second, Merrell was already pushing the weight limit. With the long-lasting Vibram Megagrip, why add more rubber than needed?

Plus, having a thin outsole means the ride feels less muted. This is often a problem in trail shoes, so it's a nice bonus.

The outsole is arguably the most important part of any trail shoe. Analyzing the Agility Peak 5, we discovered an outsole tailored for technical terrain, featuring 4.5-mm Traction Lugs lugs spaced widely apart.

There are fewer lugs than before, also enhancing the space between them. The v5 has only 31 lugs, a significant drop from the 52 of its predecessor.

One of the shoe's disappointments is its missing reflective elements.

You'd think a shoe designed for all-year, all-terrain use would include this, especially for night runs. It's important to be visible when a headlamp shines on you, but the Agility Peak 5 doesn't help with that.

The tongue is often one of the last parts designed in a shoe because it's easy to change and modify to fit the shoe's overall characteristics. 

This is a perfect example of that. We're confident that the original design for this tongue was thicker. However, when Merrell weighed the shoe, we're sure that for them it turned out to be too heavy. So, one of the simplest ways to cut down weight in a trail running shoe is to use a thinner, less padded tongue (3.3 mm).

We were surprised to find the tongue only semi-gusseted. For a shoe designed for tough, technical trails with mud or snow, a fully-gusseted tongue would have been more suitable.

While this one does its job to get a proper lockdown, it doesn't quite meet our expectations for such challenging conditions.

In the heel, there's a pull tab that's too small for our fingers, yet large enough to pull comfortably or hook a D-Ring ankle gaiter for those challenging, mud-caked trails.

The insole is completely removable since it's not glued to the midsole.

This is great, but it means if we swap out the insole, we'll lose a unique feature of this Merrell shoe—the Cleansport NXT treatment that controls odor in the standard insole.