Juuso Simpanen’s Take on Ultra 3 After 3 Ultras

Juuso Simpanen's experiences with the Ultra 3 and its Prototypes: Proven Performance Over Three Ultramarathons

I’ve had the chance to run in the Ultra 3 prototype shoes since July of last year, and I was hooked from the very first training sessions. I ended up using them for almost all of my long preparatory runs before UTMB, and ultimately chose them as my race shoes for UTMB itself. I have to say – they performed exceptionally well.

From Prototype to Race-Ready

The first prototype still had a few things to improve, but those were successfully addressed in the next version, which I got to use at Kullamannen. There, too, the shoes proved to be highly reliable. The biggest credit goes to the cushioning – there’s just the right amount for long distances, and I could easily see myself using them for even longer stages.

Outsole Grip – Crucial in Tough Conditions

The outsole deserves special mention. The grip on wet rocks and in mud has been outstanding. For example, during the Chianti race, where the trails were very slippery due to heavy rain, the tread held up extremely well in the clay-heavy and muddy terrain. I might have preferred an even more aggressive tread for the thickest mud sections, but the current design still held its own – unlike many other shoes.

Room for Toes and Solid Foot Support

One of Ultra 3’s greatest strengths is its fit. The shape of the shoe feels natural – especially around the forefoot and toes, where there’s plenty of room. This is crucial for long distances as your feet inevitably swell. At the same time, the shoe locks the foot in place extremely well, especially around the heel and midfoot, preventing internal movement – even in wet conditions. Three races with zero blisters says a lot.

Durable Materials for Distance and Time

The upper is made from breathable and lightweight material, yet it’s incredibly durable. I’ve logged well over 1000 kilometers with some pairs, and the upper hasn’t torn or frayed anywhere. I believe these shoes could easily last 2000 kilometers or more, which is exceptional for an ultrarunning shoe.

Juuso's Ultra 3's after well over 1000 kilometers.

Midsole Cushioning and Responsiveness – A Key to Late-Race Performance

The midsole material in the Ultra 3 is relatively soft but also springy – it doesn’t sap your energy, yet provides comfort even on hard, technical surfaces. In the Alps and on rocky trails, this has made a huge difference. The rock plate also protects well against sharp stones without making the ride too stiff.

Light Yet Durable – Efficient Running

What’s particularly impressive is that despite all the cushioning and structure, the shoe remains remarkably lightweight, especially for an ultrarunning shoe. This makes it easier to run efficiently and smoothly, especially on long climbs and runnable sections – like the ones I encountered frequently in Chianti.

Conclusion: The Best Shoe for 100-Mile Races

UTMB, Kullamannen, and Chianti – in all of these races, the Ultra 3 has performed flawlessly. I’ve run in many different shoes, but Ultra 3 is by far my top choice for 100-mile races. Its combination of cushioning, grip, durability, fit, and lightness makes it a uniquely dependable partner for ultradistance running.

The Ultra 3 has become my go-to shoe, and I’ll continue using it in both training and upcoming races.

Who is Juuso Simpanen?

Juuso Simpanen is a Finnish ultra trail runner and former professional footballer who now competes in some of Europe's most challenging mountain races. With wins at events like UTMB Kullamannen and strong finishes at international competitions such as UTMB Mont-Blanc, he’s become one of Finland’s top names in the sport. Juuso is also a trail running coach, helping others train smart and run strong through the mountains.

Editor’s Note:
This blog post was written based on an interview with elite ultra trail runner Juuso Simpanen. The text is presented in Juuso’s own voice to reflect his personal experiences and insights.