Bronze Winner In The Category Trailrunning
Technical trail running demands a high level of performance from footwear. These demands include precise ground contact, high-speed traction on mixed terrain, efficient energy transfer, and a fit that eliminates movement between foot and shoe under maximum effort. In the highly competitive world of high-performance trail running footwear, even slight improvements in responsiveness, stability, and weight can have a significant impact on elite athletes. The Scarpa Alien Sky was developed directly with a group of elite athletes over more than a year and a half, from initial concept through to final product. It has been recognized as a winner of the European Outdoor Award.
The Alien Sky is a high-performance trail running shoe designed for steep, technical terrain where precision and responsiveness are critical. The Super Critical Foam midsole, made entirely of A-TPU, offers 76% energy return. The PA12 nylon and 10% glass fiber forefoot plate offers explosive uphill propulsion and torsional flexibility for enhanced downhill stability. The upper integrates a seamless sock construction with an asymmetrical, football-inspired fit and a Vibram® Megagrip outsole with 4 mm lugs. As a recipient of the prestigious European Outdoor Award, it is a technically precise tool for experienced mountain runners.
What convinced the jury:
★ Super Critical Foam A-TPU Midsole:
An ultra-lightweight, nitrogen-infused 100% A-TPU foam delivers 76% energy return and long-lasting resilience, providing explosive propulsion while maintaining ground sensitivity.
★ Adaptive Forefoot Plate:
Engineered from PA12 Nylon with 10% glass fibre, the forefoot plate delivers explosive uphill propulsion and torsional flexibility for stability on demanding downhill sections.
★ Second-Skin Precision Upper:
An asymmetrical, football-inspired seamless sock upper with a minimal TPU insert eliminates pressure points, provides debris-free protection, and creates a direct, precise connection between foot and shoe.
Jury Statement:
The Alien Sky is a technically advanced trail running shoe designed for anyone who pushes themselves to the limit on the trail. Every component is designed with the same goal in mind: precision, lightness, and maximum propulsion.
Product Scoring:
Designed with athletes in mind
The Alien Sky’s development process sets it apart from conventional product development in this category. A group of elite athletes was involved from the selection of materials through every testing phase, from first prototype to final version.
This development partnership spanned more than a year and a half. The resulting product directly reflects the input. The A-TPU Super Critical Foam midsole, in its pure form, delivers 76% energy return, a figure that reflects the material’s high elasticity and long-lasting resilience, properties that standard EVA foams cannot match. The glass-fibre reinforced PA12 nylon plate is not a generic component, but a precision-engineered solution for the specific demands of steep technical terrain: maximum propulsion on ascent, controlled torsional response on descent. The second-skin upper fit, informed by asymmetrical football boot construction, eliminates the play between foot and shoe that costs athletes precision and energy at speed.
Product Specifications:
- Midsole: 100% A-TPU Super Critical Foam; 76% energy return
- Forefoot plate: PA12 Nylon + 10% glass fibre
- Outsole: Vibram® Megagrip, 4 mm lugs
- Upper: 80% TPEE + 20% PA knit mesh with seamless sock construction; minimal non-dyed microfibre lining
- TPU insert: Drop-shaped forefoot protection; absorbs impact, guides ride/flow, maintains terrain feedback
- Laces: Flat laces, 100% recycled polyester
- Weight: 235 g
- Sizes: 38 – 45½ (half sizes) + 46
- Colours: White/Azure (one colour version)
- Retail price: €229.95
- Guarantee: 2 years
ScarpaScarpaScarpaDesign & Materials
The Alien Sky integrates an outsole, midsole, forefoot plate, upper, and sock construction into a unified system with a single performance objective: maximum precision and energy return on technical mountain terrain. Each component is selected or developed for its specific contribution to that objective rather than as a generic choice from available options.
Materials:
- Laces: Flat profile for reduced pressure points and improved knot stability; 100% recycled polyester
- Midsole: 100% A-TPU Super Critical Foam – nitrogen-infused for ultra-light weight and maximum long-lasting responsiveness
- Forefoot plate: PA12 Nylon + 10% glass fibre – distributes impact forces, adds protection while maintaining full control and responsiveness
- Outsole: Vibram® Megagrip – 4 mm lugs for maximum traction on rock, mud, and extreme slopes
- Upper fabric: 80% TPEE + 20% PA knit structure; balances mechanical resistance (abrasion, tearing) with lightness
- Lining: Minimal non-dyed black microfibre lining for lightness, grip, and durability
- TPU insert: Drop-shaped; forefoot protection and impact absorption without limiting ground adaptation
Intended Use
The Alien Sky is designed for technical trail running on steep, rocky terrain:
- Steep and technical mountain trails
- Trail running races and training up to marathon distance
- High-alpine terrain requiring precise footing and responsive energy return
Target group: Experienced trail runners and professional athletes who are proficient in running mechanics and seek precision, lightness, and propulsion in demanding mountain environments. This product is not intended for use as a high-volume mileage shoe; its intended use is for race day and technical performance.
