• Discontinued
  • 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: 8oz
    Women: 7oz
  • Heel to toe drop
    Men: 0mm
    Women: 0mm

    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: 18mm
    Women: 18mm
  • Forefoot height
    Men: 18mm
    Women: 18mm
  • Width
    Men: normal
    Women: normal
  • Release date
Show more facts


We spent 6.8 hours reading reviews from experts and users. In summary, this is what runners think:

6 reasons to buy

  • Runners liked the cushioning of this shoe because it wasn’t too restrictive or stiff.
  • It features a removable insole that has a molded arch for added mid-foot support.
  • Most runners were happy with the drainage holes in the forefoot and heel, which allow water to drain off quickly.
  • The Altra 3-Sum offers great traction, a responsive ride and adequate flexibility through the blown rubber outsole.
  • It has a natural foot design for maximum comfort.
  • This shoe has an anatomical fit that lets the toes splay naturally.

3 reasons not to buy

  • The 3-Sum has a slightly expensive price.
  • There were runners who noticed that the upper unit was not as breathable as expected, especially during hot weather.
  • Some of the testers noted that the mid-sole of this running shoe was a bit thin and inconsistent in terms of cushioning.

Bottom line

The Altra 3-Sum is a lightweight zero-drop shoe ideal for road running. This shoe offers comfort, flexibility, and a smoother ride. It is a great option for daily training.


Expert Reviews

Experts are runners, who post reviews at youtube, directly at RunRepeat or at their own websites. Each expert is categorized from level 1 to level 5 based on expertise. See stats on expert reviews and how we calculate scores here.

Are you an expert? Apply to contribute here.

84 / 100 based on 4 expert reviews

  • 90 / 100 | Running Competitor

    The more efficient your stride, the more you’ll reap the benefits of this shoe’s unique design features and low-profile construction.

  • 85 / 100 | Runner's World

    For efficient runners on race day.

  • 80 / 100 | Runner's World

    On this version, the upper is a single mesh layer for superior on-skin feel.

  • 80 / 100 | Runner's World

    On this version, the upper is a single mesh layer for superior on-skin feel.

Apply to become an expert

Updates to Altra 3-Sum

  • The Altra 3-Sum features the SpeedPod outsole that follows the natural built of the foot. This is design to provide added flexibility and responsive ride. This technology comes with a rubber compound for added durability.
  • The midsole of the shoe uses EVA foam that provides durable cushioning. This works perfectly with the Natural Ride System for natural foot movement and the natural foot design for maximum comfort.

Altra 3-Sum size and fit

The 3-Sum is available in standard length and width. It has a medium measurement in the heel and midfoot area while the forefoot is wide enough to accommodate wider foot measurement. The shoe is great for runners with medium and wide foot measurements.


The SpeedPod outsole is strategically placed underfoot to support the bones from the moment the foot lands until it springs for toe off. The blown rubber outsole is primarily used in the outsole for excellent traction in varied areas and in inclement weather conditions.


The midsole is made up of the Altrabound foam for plush cushioning and the average dual density EVA foam for the right amount of aggressive response in the midsole. Another feature of the midsole is the Natural Ride System that is designed for proper foot mechanics and natural foot movement.


The upper of the Altra 3-Sum comes with the quick-drying air mesh that wicks water away while keeping light and breathable. The seamless upper is designed to reduce irritation and provide a sock-like comfort. The asymmetrical lacing follows the natural shape of the foot that also improves the overall fit and feel.