Asics Fuji Speed 4

Lightweight Speed for the Trail Ahead

When speed meets precision on rugged terrain, the result is the Asics Fuji Speed 4 — a high-performance trail running shoe built for racing, training, and chasing fast times off-road. Whether you’re attacking a technical mountain trail or pushing the pace through forest singletrack, the Fuji Speed 4 is designed to keep you moving light, fast, and focused.

Lightweight Agility, Race-Ready Design
Engineered with a minimalist approach, the Fuji Speed 4 features a breathable MOTION WRAP™ upper that wraps the foot for a secure, race-ready fit with minimal weight. The gusseted tongue and refined lacing system reduce pressure points and keep debris out, while the reinforced toe bumper offers protection when the trail gets aggressive.

Fast and Responsive Underfoot
The midsole houses FF BLAST™ PLUS cushioning, delivering a responsive and energetic ride with excellent impact absorption — ideal for running at pace over uneven terrain. Beneath it all, a full-length carbon-infused plate enhances propulsion and efficiency, helping you maintain speed and rhythm through undulating trails and technical descents.

Traction You Can Trust
The outsole features ASICSGRIP™ rubber with a new, multi-directional lug pattern that grips reliably on loose gravel, mud, roots, and rock. Whether climbing or descending, you'll stay grounded and confident no matter the surface or conditions.

Built for Trail Runners Who Race
The Fuji Speed 4 is purpose-built for trail runners who value speed and efficiency. It excels in events from 10K trail races to ultra-distance competitions, offering a blend of lightweight responsiveness and all-terrain grip. If your training involves tempo sessions on trails or if you're aiming for a podium finish, this shoe delivers the tools to perform.

Key Features:

• Weight: Approx. 240g (men's US 9)
• Stack Height: 34mm heel / 26mm forefoot (8mm drop)
• Cushioning: FF BLAST™ PLUS
• Plate: Carbon-infused propulsion plate
• Outsole: ASICSGRIP™ with aggressive lugs
• Upper: MOTION WRAP™ with reinforced overlays

Whether you’re racing through the mountains or training for your next trail challenge, the Asics Fuji Speed 4 gives you the lightweight speed, grip, and protection you need to run your best when it matters most.

US sizing shown unless stated otherwise. View size charts here