Brian: The Rivera fits true to size with a medium width in the heel and arch and just a touch more room in the forefoot. (It doesn’t feel nearly as roomy as most Altra shoes, but there is room for the toes to wiggle and splay.) The Rivera’s step-in feel is soft, smooth and comfortable, and it oozes a light and agile performance-oriented vibe the moment you start running in it. The EGO midsole is as soft and springy as ever and performs very well throughout all workout speeds and distances. I’m confident that the shoe will sustain its performance for another 300 kilometers before starting to break down.

In addition, the shoes have grippy outsoles with abrasion-resistant lugs to offer a natural movement of the foot and provide excellent traction on asphalt and off the trails. The reflective elements on the heels for enhanced visibility perfectly round off the shoes’ features. No matter which surface you enjoying running on, you’re guaranteed to feel comfortable in the functional and fast Rivera 2. At this price point, the Rivera will go up against the likes of Brooks Ghosts, Saucony Ride, New Balance 880, and the Topo Athletic Cyclone (maybe the closest comparable shoe, review to come shortly).The Inner Flex tech and resulting flexibility of the Rivera is maybe a bit overdone for my tastes removing a bit too much toe off snap for my tastes especially when combined with the easy going upper. The next characteristic of all Altra shoes is that they are designed with Balanced Cushioning™. Most shoes have more cushioning in the heel than the forefoot, causing a slightly downward slope that you may have heard of as “heel-to-toe drop.” Every Altra shoe is built on a platform where the heel and forefoot are an equal height from the ground, which makes all Altra shoes Zero-Drop™. Altra designed this to help with optimal alignment, cultivate better form and encourage a low-impact landing. It also takes the pressure off the ball of your foot. Up front we have longitudinal pads of only slightly softer rubber than the rear protruding from above deep grooves into the midsole. In conjunction with the Inner Flex grooves into the top of the midsole we have an easy but not overly easy long flexing shoe with the broad forefoot platform and outsole contributing to good front stability. Brian: The one-piece upper is made from an engineered mesh material that’s pliable and accommodating, but it’s also supportive when the laces are snugged down. It’s very breathable and airy with very few seams or stitching. The upper material is slightly reinforced to supplement the protection the toe bumper provides, but also to help provide enough shape to keep the material from rubbing the top of the toes.

Sam: The change here between versions is the upper with the Rivera 2 delivering a more characteristic Altra broad front fit than Rivera 1. The fit now leans a bit more comfort than performance but that is OK by me. Kurt Huebner is a senior at Cornell University who spends far more time thinking about running than studying. He has mainly focused on ultramarathon training for the last two years, with a 8:00:00 50 mile PB. Kurt is also a competitive nordic skier and will put on a race bib for just about any endurance sport, from snowshoeing to marathon canoeing. On the side, Kurt works at a local run specialty store. He has been averaging about 45 miles a week this winter.Altra Rivera 2 is famous because it is lightweight and more responsive than 3, which allows natural foot movement while running. Upper is surprisingly supportive and for sure comfortable for such as light extremely pliable and soft mesh