Be Lenka - Core - Black - (Unisex)

FootShape™ is exactly what it sounds like—a toe box shaped like your foot. This design gives your toes the space to spread naturally. Once your toes adjust to spreading out, they will become more powerful and stable, resulting in stronger strides, better balance, and fewer injuries. Whether you’re running trails, pounding pavement, or just roaming about, FootShape™ helps your feet do what they were designed to do.

Traditional shoes typically feature a 12mm drop from heel to forefoot, whereas the Altra shoes Balanced Cushioning™ platform places your heel and forefoot at the same distance from the ground (zero drop). This natural setup encourages better alignment, low-impact running form, and a softer landing with every step.

The size chart for each product shows the inner length of each shoe model. Your toes should always have space to move freely: this is especially important for running. 

We recommend approx 12mm of space in front of your toes (no less than 6mm and no more than 18mm). Refer to our comprehensive Find your Perfect Fit page for guidance on exactly how to measure your feet and choose the right size.

Still not sure? Reach out to info@bprimal.com — the team is always happy to help.

They’ll fit like a traditional athletic shoe from heel to ball, but the toe box is different: it lets your toes spread out, breathe, and move freely. A good rule of thumb? If they don’t feel a little roomy in the toes at first, they’re probably too small. Your toes should feel completely unrestricted!

When you receive your shoes, spend some time wearing them indoors to get used to them and decide whether they are right for you.

It depends on how far and often you roam, but they are designed with all distances in mind! The core training models are designed for walking and running any distance—from 5k to UltraMarathons. Just like any trusted adventure companion, the more you use them, the quicker they’ll wear.

Yes! Due to the FootShape™ design, most people—including those with wider feet—find them comfortable. Altra shoes are standard width at the ball of the foot, but the FootShape™ toe box gives your toes room to spread out naturally. For extra space, you can also remove the insoles (if you don't mind sacrificing a touch of the cushioning.)

Yes again. Even with the roomy FootShape™ toe box, the rest of the shoe is designed with a standard fit, so narrower feet will still feel supported while enjoying that natural toe freedom.

Yes. By placing the foot in its natural position (flat with toes spread), Altra shoes are designed to encourage a proper, low-impact running form. This helps reduce the impact of heavy heel striking and promote a lighter, healthier stride.

Yes, Altra shoes are designed to work with insoles and orthotics. For the best fit, insoles generally pair better with higher volume Altra models. As your feet gradually strengthen over time, the necessity to wear supportive insoles or orthotics should reduce.

Altra shoes don’t have built-in arch support, but here’s the magic: placing your foot in its natural position with a level heel and extended big toe helps your arch strengthen and support itself.

It's common to experience some soreness in your lower calves and feet when transitioning to Altras, especially if you're coming from traditional running shoes with an elevated heel. This is due to the Balanced Cushioning™ platform, which encourages a more natural foot strike and engages your lower leg muscles differently.

Most people feel this adjustment for about 2 to 3 weeks, which is a sign your body is adapting to a more natural running form. A simple heel lift (available at most running stores) can help ease the transition during tougher workouts.

Definitely. Just like any skill, learning the fundamentals early makes all the difference. Altra’s FootShape™ toe box and Balanced Cushioning™ platform help put your feet in their natural position, encouraging a low-impact, natural running style. This means less strain, more enjoyment, and a stronger foundation for your running journey.

Cleaning is simple—as soon as they get dirty, give them a gentle hand wash using a damp cloth and mild detergent (do not machine wash or dry). You can stuff your shoes with a towel or a shoe saver to help them dry naturally and keep their shape.