Everything you need to know to run your first trail — and to prepare your next ultra. Elevation gain, cut-offs, gear, nutrition and the UTMB/ITRA qualifier systems.
Trail runs on dirt, rock, roots and snow — not asphalt. Every step is different. That burns more and demands more attention, but the views make it worth it.
In trail you run by effort, not pace. Climbing 1,000m at 5 km/h is harder than running flat at 10 km/h. The ITRA formula converts D+ into equivalent effort-km.
Trail races have checkpoint time limits. If you arrive late, you're pulled. It's not elitism — it's safety in the mountains where rescue teams need to withdraw at nightfall.
ITRA km-effort formula: trail pace = road pace × (1 + D+ / (100 × km)). Excludes ultra fatigue multipliers.
A 30K with 2,000m D+ is harder than a road marathon. Positive elevation gain (D+) measures total meters you climb — and determines actual effort time.
< 1,000 m D+
Perfect for your first trail. Trails with some climb but no mountain technique required.
1,000 – 3,000 m D+
Poles and technical experience needed. Temperature can drop 10-18°C at the summit.
3,000 m+ D+
Experienced runners only. Snow, extreme cold and some alpine technique required.
ITRA formula · international standard
effort-km = distance (km) + D+ (m) ÷ 100
Example: Ultra Coahuila 100K / 4,767m D+ → 100 + 47.67 = 147 effort-km. That's almost a full extra marathon.
NTL uses this formula with fatigue multipliers (×1.05 ultra, ×1.12 hundred miles) in the Pace Calculator on every event page.
Each aid station has a maximum arrival time. If you're late, the race pulls you — not because you're slow, but because darkness has reached the mountain and the rescue team needs to withdraw.
Your estimated time in the NTL Calculator is lower than the cut-off → ✓ green. You're on pace.
You arrive with under 30 min margin. Consider starting faster or training your climb pace.
Your current pace doesn't make the cut → ✗ red. Adjust your pace or choose a shorter distance of the same event.
The Pace Calculator on every event page shows your ✓/✗ in real time as you move the pace slider.
go to calendarCombine your road pace with your real weekly D+ gain and get an instant traffic light: ready ✓ / adjust ⚠ / not yet ✗. Calibrated against real cut-off times from the race calendar.
Trail Readiness Index
Combine your road pace and weekly D+ to see if you're ready for a specific race.
Adjust
Tight margin — 1h 4min left before cut-off
Ready
600m D+/week ≥ 436m recommended for Build phase
Adjust
Almost there. Check the specific detail in pace or D+ and adjust.
Cutoff times based on real NTL event data. D+ targets: 28% of race D+ per week in Build phase (ITRA km-effort methodology).
💡 Your Garmin / Apple Watch measures how recovered your body is today. NTL measures whether you're ready for the specific D+ and cut-offs of your target race. They're complementary, not competing.
Lugged outsole. Road shoes will slip on wet roots.
Minimum 1.5L. For ultras, carry 2L.
500 ml/hour — more in heat or at altitude.
1 gel every 40 min or fruit/nuts/potatoes.
Temperature can drop 10-25°C with elevation gain.
Mandatory in pre-dawn starts or races over 6-8h.
Bandages, blister patches and pain relief.
Don't rely on your phone or cell coverage.
280 kcal per hour
The baseline rule for endurance trail. Your body can't absorb more while moving.
1 gel every 40 minutes
In races under 6h. In ultras, gels supplement — not replace — real food (potato, banana, broth).
500 ml water per hour
More in heat or altitude. Add electrolytes (salt tabs) if you're sweating for more than 6 hours.
personalized calculation
calculate your nutrition with your actual pace.
The Pace Calculator on every trail event has a Nutrition tab: adjust your pace and see how many gels and liters you need for each distance — live.
go to an event and calculateThe most ambitious qualifier system: each qualifying race earns 'Running Stones'. Accumulate enough and you can enter UTMB Mont-Blanc — the Champions League of ultra-running.
Example: Chihuahua by UTMB (100K) = Running Stones for UTMB.
see qualifier racesYour global trail ranking. Each ITRA Qualifier race contributes to your Performance Index based on your finish position. Track it against the minimum PI required for your target race.
Example: Ultra Coahuila 2026 is ITRA Qualifier ID 100342.
see qualifier racesAdjust your pace and see in real time when you'll arrive at the finish and each aid station. Shows whether you beat the cut-off.
Weather forecast, checkpoint cut-offs, gear checklist and your training phase — all in one shareable link for your crew.
A 16-week plan calibrated to your target race's D+. Saved on your phone. Share it on WhatsApp.
Choose a 10-15K race with < 500m D+
Use the 'first trail' filter in the calendar. Look at terrain, not just distance.
Verify you can beat the cut-off
Open the Pace Calculator on the event page. Set your pace (start at 10-11 min/km) and check the ✓.
Prepare the mandatory gear
The event page lists the specific gear calibrated for that race and elevation profile.
Download the GPX to your watch
The 'Export for watch (.gpx)' button in the Calculator generates a file with all checkpoints and estimated arrival times.
Add the race to your calendar
'Add to calendar' button on the event page. Your phone alerts you 48h before with the briefing link.
Upcoming races from the NTL calendar — with verified elevation data. Pick your level and start planning.
the mountain doesn't ask your pace. only if you'll return.
In ultras >6h to prevent hyponatremia.
Mandatory in most high-mountain races.
The most technical series: skyrunning and fast mountain races. More oriented toward competitive format than ultra endurance.
Example: UTMX Tepec Trail 36K is a Golden Trail qualifier.
ETA at each aid station so your crew knows where to find you. Includes pace wristband and drop bag cards.
Generate your certificate with name, race, distance, D+ and zone ranking. Download-ready for Instagram.
Your mountain running history: total D+, trail km, zone rankings. The runner profile no other platform has.
Read the Race Day Briefing the Friday before
Updated forecast, cut-offs, final gear check and training phase — one shareable page for your whole crew.
Ultra Basaseachi 2026
Aug 23, 2026
Basaseachi, Chihuahua