Istria 100 by UTMB® 110K

Race strategy

Hold a steady pace and save energy for every section.

• 1039m descent. Go easy, save your quads.
• The finish is runnable. Save your legs to run it all the way.
• Long race. Control your HR and effort. Early mistakes cost the most.
• Control your HR on the first climb, save your quads on the descents until 65.8km, then run your race pace.
• Start · 0.0km–1.7km · Race-day nerves push your heart rate up: don't follow the crowd, find your own rhythm.
• Settle in · 1.7km–15.2km · Climb of 582m. Ease in: hold back more than feels necessary. The race is still ahead. Climb by heart rate or breathing, not pace. Running pays off here: run wherever you can.
• Work · 15.2km–55.7km · Descent of 325m averaging 12%, descent of 1039m averaging 9%, descent of 327m averaging 11%. Plus 3 more climbs. This is where the race is built: steady, solid effort. Climb by heart rate or breathing, not pace. This descent is hard on the legs: short steps, stay in control, poles if you have them. Running pays off here: run wherever you can.
• Fade · 55.7km–85.0km · Descent of 388m averaging 12%, climb of 887m. Plus 1 more climb. Your energy fades, and that's normal: hold a steady effort and stop counting the miles. Climb by heart rate or breathing, not pace. This descent is hard on the legs: short steps, stay in control, poles if you have them. Your heart rate drifts down on its own: don't chase your early-race numbers, go by feel.
• Home · 85.0km–110km · 25.2km of runnable trail. No heroics: settle back into your own effort and hold it to the line. Running pays off here: run wherever you can.

Course

The course climbs 4074m+. With 37m/km of climbing, this is a rolling, mostly runnable course. By gradient, 32% of the distance is uphill, 33% downhill and 35% flat. The longest climb runs 19.3km at an average 4.6% grade (887m of vertical). The longest descent runs 11.6km at an average 9.0% grade (1039m of vertical). The steepest climb averages 24.1% over 0.7km. The steepest descent drops at 30.7% over 0.2km. Surface: 46% trail, 31% smooth, and 19% road. Flat-equivalent effort: 135.1 FlatKM.

Summits

The highest summit on the course is Gomila (1027m), 23.5km from the start. Other named summits along the route: Žbevnica (1014m). The course also passes close to Lobardina (888m).

Poles

Poles bring little benefit here: only about 14.6km of pole-friendly terrain.

Quad damage

Quad damage risk is moderate (index 46 of 100), with 64% of the load in the first half: 4 descents deserve a plan and a couple of downhill sessions before race day.

• Control your HR on the first climb, save your quads on the descents until 65.8km, then run your race pace.
• #2 · 23.5–26.2 km · 325 m D−, -12.1% · 84.1 km ahead → control
• #1 · 31.3–42.9 km · 1039 m D−, -9.0% · 67.4 km ahead → control
• #3 · 52.7–55.7 km · 327 m D−, -11.0% · 54.6 km ahead → control
• #4 · 62.6–65.8 km · 388 m D−, -12.3% · 44.5 km ahead → control

Weather

On race day, start temperatures have historically ranged from 6°C to 13°C, with around 8°C at the highest point; the chance of precipitation is about 39%. Heavy rain of 10.0mm or more falls on about 9% of days around this date.