Alpinestars A-Impact Plasma Protection Shorts Review 2026

Alpinestars developed the A-Impact Plasma Protection Shorts using feedback from elite mountain bike athletes, the kind of riders who push into terrain where crashes are not a question of if but when. The result is a protective short that takes impact management seriously, deploying Nucleon Plasma technology across multiple protection zones and building the chassis around active riding rather than simply bolting pads onto a standard short.

The headline specification is the removable CE Level 1 certified Nucleon Plasma Hip Protectors. These are constructed from a USDA Certified Biobased viscoelastic material, which is a meaningful distinction from conventional foam padding. Viscoelastic materials are pliable in normal use, conforming to the rider’s body and moving naturally through the riding position, but they dissipate impact energy when struck. The biobased composition adds environmental credentials to a genuinely performance-driven material choice. The protectors are removable for washing the shorts, then reinsert cleanly for the next session.

Two Nucleon Plasma Lite Side Pads provide additional upper leg coverage, addressing the outer thigh area that takes significant impact in typical trail and enduro crashes. The ergonomic scooped cut at the front eliminates the discomfort that flat-fronted protection shorts create in the lower abdominal area when seated, a detail that matters on longer enduro stages. Abrasion-resistant outer textile over the protector pockets adds durability where the fabric takes the most contact during falls.

The main chassis is a soft, tactile, highly breathable stretch mesh that prioritises cooling performance and mobility, ensuring that the protective structure doesn’t compromise riding dynamics. Silicone-backed hem at the bottom prevents the shorts from riding up during hard efforts. Additional PU foam padding on the back provides lower spine coverage.

Who is the Alpinestars A-Impact Plasma Protection Shorts aimed at?

The A-Impact Plasma Protection Shorts are for enduro, downhill, and aggressive trail riders who want CE-certified impact protection without wearing full hard-shell armour. They suit riders who tackle technical terrain, bike parks, and trails where hip and leg impacts are a genuine risk, and who want protection that performs on long descents without overheating or restricting movement. The chamois tuning for enduro and gravity disciplines makes these particularly relevant for multi-stage enduro events and extended gravity-focused days.

Specifications:

– CE Level 1 certified Nucleon Plasma Hip Protectors (EN 1621-1:2012 Level 1): USDA Certified Biobased viscoelastic material, pliable and impact-dissipating, removable for washing
– Nucleon Plasma Lite Side Pads for additional upper leg coverage
– Dual-density chamois specifically optimised for enduro and gravity disciplines
– Breathable stretch mesh main chassis for cooling and mobility
– Ergonomic scooped front cut for seated comfort
– Abrasion-resistant outer textile over protector pockets
– Silicone-backed bottom hem to prevent riding up
– PU foam padding for additional lower spine coverage

The A-Impact Plasma Protection Shorts justify their £129.99 price through genuine engineering decisions: Nucleon Plasma viscoelastic technology, CE Level 1 certified coverage, a gravity-tuned chamois, and a breathable chassis that keeps the shorts wearable on long descents. For riders who ride into impact territory, these are built for the job.