Bottom Line
Tested in Alaska’s alpine environments, the Mammut Runbold IV showed some of the best mobility and breathability of any pair we tested in our lineup of men’s hiking pants. When we need pants that are extremely mobile for clambering over rocky summits, the Runbold IV is our first choice. Its athletic cut – combined with highly elastic material – hugs the body without being restrictive.
The Runbold IV accompanied us for miles across Alaska’s rugged backcountry, proving itself to be a worthy companion. Its UPF 50+ UV protection is great for sunny high altitude days, and its quick-dry material sheds moisture and adds breathability for aerobic activities.
The European sizing and athletic cut make the Mammut Runbold IV best suited for slender bodies. Even then, sizing can be tricky. You may need to size up for a better fit. Plus, this pant doesn’t offer much in the way of weather resistance – but does dry quickly. After repeated testing, the Runbold IV has proven to be one of our favorite pairs of pants. It’s packed with high performance features and a well thought out design.
How We Tested
We tested the Mammut Runbold IV over four months on Alaskan trails and summits. We tested the durability by thrashing through dense brush and kneeling on gravel and evaluated breathability on high exertion hikes to deliver the most comprehensive and well-rounded review possible.
Quick Specs
Men’s Mammut Runbold IV
Best Lightweight Hiking Pants
CleverHiker Rating: 4.7/5.0
Price: $119
Weight: 10.3 oz.
Fit: Slim
Fabric: 85% polyamide, 15% spandex
Pros
- Lighweight
- Stretchy for high mobility
- All pockets zippered
- Dry quickly
- Adjustable Velcro tabs at hip
Cons
- No elastic to roll up legs
- Slim fit can feel tight for thicker legs
Comfort & Mobility
With a nylon and spandex blend, the Runbold IV is highly mobile and elastic. We loved wearing these pants when clambering over boulders, taking large steps, and making awkward movements.
With an athletic cut, the Runbold IV is a slim-fitting pant that fits slender bodies better. However, we weren’t encumbered by any restrictive “skinny jean” feelings. Its four-way stretch allows more freedom of movement than most pants in our lineup. The polyester lining is soft and comfortable. Slipping these pants on feels like putting on a second skin. These are the type of pants that we feel comfortable wearing day after day, hike after hike.
Breathability
Testing these pants in both cool spring weather and warmer temperatures, it was immediately apparent that the Runbold IV is built to breathe. We even wore these pants on a few short jogs and were surprised at how well they managed heat and sweat. We reached for these pants often when we knew we were going to be exerting ourselves. The Runbold IV also dries quickly – whether from sweat or rain. It remains one of our top choices for a breathable pant for the rigors of the trail.
Weather Resistance
This breathability costs the Runbold IV in weather resistance. In our testing, the pant wet quickly at the first sign of rain – it beaded only the lightest moisture before wetting through.
If you’re looking for a pair of pants for days spent in inclement weather, there are better options out there. However, we were impressed with the Runbold IV’s ability to cut the wind on dry and blustery days. Their nylon shell is similar to the material of many windbreakers and does a decent job of blocking gusts. Although they wet through quickly, the Runbold IVs also dry quickly, making them good for passing in and out of light precipitation.
Durability
Despite their thin and airy material, we’ve been impressed with the Runbold IV’s durability. During our testing, we kneeled in gravel and scraped against rocks while scrambling across rocky summits – the pant took a beating without showing signs of abrasion or scratches.
Even so, these are not our top choice when we’ll be bashing through brush or coming in contact with the ground often. Their thin material does not protect the legs as well as others. However, during our testing, we have yet to see these pants fail in the face of brush, rocks, or impact. These lightweight pants are solidly built and should continue to hold up to years of use.
Features
With two hand pockets, one thigh, and one back pocket, the Runbold IV features all-zippered closures to secure your items. The biggest standout feature is the pant’s velcro waist tabs to dial in the fit. Although the Runbold comes equipped with belt loops, these tabs keep the pants secure, all but eliminating the need for a belt.
The one feature we found these pants lacking is some kind of roll-up closure for the hems. This would only enhance the comfort and performance of these lightweight pants. With just enough features to be functional without being overly techy, the Runbold IV rides the line between performance and casual, tipping slightly towards performance.
Should You Buy the Mammut Runbold IV Pants?
The Mammut Runbold IV is a technical pair of pants that is great for warm days and alpine adventures. Its lightweight performance and UPF 50+ UV protection make it a favorite for summer temps. Though it lacks the weather resistance for colder temperatures, inclement weather, or shoulder season hikes, it excels as an extremely breathable, summer-weight option. Its European sizing and athletic cut make the Runbold IV best suited for slender bodies. In spite of its tricky sizes, it’s quickly become one of our favorite pants for summer summits.
What Other Hiking Pants Should You Consider?
Check out our full gear guide to see all our favorite hiking pants.
Rab Incline Light Review: Another lightweight option, the Incline Light is great for warmer weather.
Outdoor Research Ferrosi Review: One of our perennial favorites, the Ferrosi combines light weight with durability for a great, all-around hiking pant.
REI Trailmade Review: If you’re looking for a more affordable pair of pants with a less technical look, the Trailmade may be what you’re after.
