Review: Merrell All Out Crush

Mud, obstacles, rocks, water hazards, scrambles … or good old-fashioned trail running. Merrell’s All-Out Crush is built to thrive on all of them.

Merrell All Out Crush Features

• Stack heights: 24mm heel, 18mm forefoot
• 6mm heel-toe drop
• Breathable mesh upper with TPU overlays
• Traditional lace closure
• Protective toe cap
• Reflective details
• Integrated EVA footbed
• TrailProtect flexible rock plate
• M-Select grip outsole with 5mm lugs
• Vegan construction
• 5 color options
• Weight: 7 oz. (each)
• MSRP $110

Built for good, old-fashioned butt-kicking races

As obstacle course racing (OCR) has grown in prominence, a subcategory of gear intended for that specific type of event is emerging. Such is the case with Merrell’s All-Out Crush, a shoe designed primarily for obstacle races, but with good crossover potential for regular trail running and other outdoor activity. We tested these shoes for about 150 trail running miles, including a 2-day, 56-mile fastpack adventure in Yosemite National Park that included river crossings, peak scrambles, and trail conditions ranging from hard granite to deep sand.

What makes an obstacle course shoe, you ask? Primarily it’s the ability to thrive in sloppy conditions, since much of OCR includes water immersions and muddy terrain. The All-Out Crush addresses this need from above and below. The upper is highly ventilated to drain water and dry very efficiently, while the outsole has very aggressive 5mm lugs that provide strong traction even in extensive mud.

OCR races tend to be shorter overall distances than ultras, but you’re often running on legs that are blown up from negotiating the obstacles, so lightweight construction is also a premium feature for these competitions. The All-Out Crush is super lightweight to improve quick leg turnover, but has enough stack height to provide decent cushioning, and the flexible rock plate in the midfoot and forefoot absorb impact forces on hard terrain. A protective toe cap adds some addition protection in front of the shoe. The amount of comfort and protective features in such a lightweight shoe is one of the most impressive combinations we’ve seen this year.

Fit of the shoe is nice and solid, with a traditional lace system holding the midfoot securely in place. Moderate padding around the ankle collar and on the tongue hold the foot comfortably, and the toe box is roomy enough to allow full toe splay on impact. The same upper design that allows water drainage and rapid drying also offers great ventilation when conditions get warm, so the All Out Crush is a nice option for hot trail days. There is great flexibility throughout the shoe, which came in handy when seeking tricky foot holds while rock scrambling.

The primary drawback in our testing was that the ride of the All Out Crush is pretty clunky on hard surfaces. If you’re running through the neighborhood to the trailhead, don’t panic at first: the shoe will feel way better once you hit the dirt than it does on asphalt. This is a true trail dog, equally capable in wet sloppy conditions or for standard off-road run training.

The Good

• Excellent outsole traction
• Great ventilation and drying from upper
• Optimal combination of lightweight and comfort features

The Bad 

• Poor responsiveness on hard surfaces
• Black color is a little bland

The Bottom Line: Merrell All Out Crush

Built for OCR but well–suited for a much wider variety of off-road use, the Merrell All-Out Crush is an excellent lightweight high-performance option for fast race times or multi-day comfort.

Buy Now: Available from Backcountry.com