• Terrain


    Shoes best for road, track and light gravel. See the best road shoes.


    Shoes best for trail, off road, mountains and other unstable surfaces. See the best trail shoes.

    Good to know

    As long as you stick to the road or path, and if you want just one running shoe, buy a road running shoe.

  • Arch support

    Neutral / cushion / high arch

    Shoes for runners who do not need any additional arch support (Around 50% of runners). Best for people with normal, high or medium high arches. See the best neutral shoes.

    Stability / overpronation / normal arch

    Shoes for runners who need mild to moderate arch support (Around 45% of runners). Best for runners with a low arch. See the best stability shoes.

    Motion control / severe overpronation / flat feet

    Shoes for runners who needs a lot of arch support. Best for runners with flat feet. See the best motion control shoes.

    Good to know

    - Rule of thumb: If in doubt, buy neutral shoes to avoid injuries.
    - More about arch support in this video.
    - Find your arch type by following steps from this video.

  • Use

    Daily running

    Cushioned shoes for your daily easy running. Great comfort. See best shoes for daily running.


    Lightweight shoes good for races, interval training, tempo runs and fartlek. Here are the best competition running shoes.

    Good to know

    If you want just one pair of shoes, buy a shoe for daily running.

  • Price
  • Weight
    Men: 8.3oz
    Women: 7oz
  • Heel to toe drop
    Men: 6mm
    Women: 6mm

    The height difference from the heel to the forefoot, also known as heel drop, toe spring, heel to toe spring or simply drop.

    There are many opinions about what a good heel drop is. We do not recommend any in particular. Lean more in this video.

  • Heel height
    Men: 23mm
    Women: 23mm
  • Forefoot height
    Men: 17mm
    Women: 17mm
  • Width
    Men: Normal
    Women: Normal
  • Release date
Show more facts


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  • The Merrell All Out Crush Tough Mudder 2 BOA is an update to a fresh series of off-road shoes that are meant for muddy obstacle course events such as the Tough Mudder. It features a new upper construction, utilizing open-weave mesh and printed overlays to deliver a breathable and secure coverage. The unique BOA® lacing system makes it easier to adjust the fit.
  • Underfoot cushioning is provided by a full-length foam midsole. It’s meant to keep the foot save from impact and other hazards on the trails. A pad is placed in the platform for additional protection. Multidirectional gripping lugs on the outer side of the sole unit ensure traction over dry and sloshy surfaces.

The men’s version of the Merrell All Out Crush Tough Mudder 2 BOA is half-a-size smaller than the regular measurements, but the women’s iteration is true to size. Males should get one that’s half-a-size bigger to have an accommodating in-shoe experience.

The width profiles are B – Medium and D – Medium for women and men, respectively. The form-fitting façade and last welcomes the natural curvature of the human foot.

The M Select™ GRIP is an outsole compound that’s meant to protect the rest of the underfoot platform from the abrasive nature of the trails. It is also the one responsible for doling out surface grip. This outsole material has been used in almost all Merrell running shoes.

Aggressive gripping lugs make the All Out Crush Tough Mudder 2 BOA more traction-ready. The multi-directional construction of these protrusions permits a well-rounded experience on the trails, especially when handling slopes and muddy paths.

A full-length unit made of ethylene vinyl acetate or EVA offers underfoot cushioning. It has a soft nature that keeps the foot comfortable. Its responsive nature enriches the toe-off and tempers the force of impact during the landing phase.

An EVA footbed has been integrated above the last of this shoe. Its goal is to bring a soft feel for the foot-pad. It isn’t removable; it won’t slide around the interior chamber during obstacle course racing.

The BOA version of the Merrell All Out Crush Tough Mudder 2 makes use of Synthetic Mesh as its main upper component. It has a traditional open-weave design for breathability and water drainage, as well as multiple layers to heighten durability and support.

There are thin synthetic overlays to bolster the structural integrity of the façade. These thin add-ons also help in providing a secure coverage.

A toe cap protects the forefoot section from abrasion. It also prevents the toes from boring holes through the fabric.

A Lycra lining brings a smooth wrap for the heel, thus preventing hot spots and blistering.

Running in low-light conditions becomes safer with the reflective detailing that’s added to the upper. Such a feature is helpful when deciding to run at night.