The 2027 Endurance is the simplest event to describe and the hardest to play well.
24-minute time cap. You run 3 km. The moment you're done, you move to the SkiErg and accumulate as much distance as possible until the clock. Your score is the ski distance. Nothing else.
The run earns no points. It spends your skiing time.
That's where it's won, and that's where most athletes leave score on the table without noticing.
The trade-off, in one line
The faster you run, the more SkiErg time you have left — but the more broken you arrive.
Put numbers on it. Run your 3 km in 12 minutes and you have 12 minutes of skiing. In 14, you have 10. Two minutes of skiing is between 400 and 600 metres depending on your level: that's enormous.
But if those two minutes cost you arriving at 95 % of max heart rate, your SkiErg output collapses over the first four minutes, and you give back more than you gained.
⇒ There is no universal right answer. There is your answer, and it is measured.
What you need to know about yourself
Three numbers, and none of them is on your watch by default.
One — your ski distance over different durations, fresh. 10, 12, 14 minutes. That's your ceiling, the one you'll never hit on race day but which serves as your reference.
Two — the drop-off. The same ski distance, but arriving from a 3 km run at three different paces. That's what tells you what the run actually costs you.
Three — the transition time. Between finishing the 3 km and producing power on the SkiErg, seconds pass. For some athletes that's ten seconds. For others it's forty — the time to get air back, find the position, not blow up.
Those three numbers are enough to build your pacing. Without them, you improvise.
The test protocol
Three sessions, at least 48 hours apart.
Session 1: the ceiling
Fresh, after a warm-up: 12 minutes of SkiErg, maximum distance. Note the distance and your average heart rate.
That's your theoretical ceiling. On race day you'll be below it. The question is by how much.
Session 2: the event, controlled pace
The full event: 3 km run at a pace you could hold for 10 km, then SkiErg flat out to 24 minutes.
Note: run time, transition time, ski distance, and your heart rate the moment you start skiing.
Session 3: the event, fast pace
Same thing, but the 3 km run 45 to 60 seconds faster.
Compare the two ski distances. Three cases:
- Ski distance goes up → you can still run faster. Test again, faster.
- It's the same → you're at the optimum. That's your pace.
- It drops → you went too hard. Go back to session 2's pace.
That's it. Three sessions, and you know your pacing for the whole season — the event doesn't change.
The problem: those numbers can't be written down
Try it, and see.
You've just finished 3 km. You're in oxygen debt. You have to check your watch, memorise it, then later compare it to the transition time you're supposed to be counting, then to your ski distance, then to your heart rate at the exact moment of the switch.
Nobody does this. And that's why most athletes leave that session with one piece of data — the final distance — when the useful information was in the breakdown.
What the watch does for you
That's the problem we built ATmetrYX for, a Garmin app available on the Connect IQ Store.
In Training mode, you pick the Endurance pillar. One press marks the run-to-ski switch. The watch records the rest: run duration, exact moment of transition, ski block duration, and heart rate continuously across the whole session.
You read your profile afterwards, calmly, instead of trying to memorise it while gasping.
And because all three protocol sessions are recorded in the same format, they're directly comparable — which is what makes session 3's test usable, instead of resting on two numbers scribbled in a notebook you then have to find.
How to train run-to-ski
Beyond the test, three session formats that work this event specifically.
The dry transition. 4 × (800 m hard run + 3 min SkiErg flat out), 3 min rest. You're training the switch, not the distance. It's the format that improves transition time most.
Skiing in debt. 1.5 km run hard, then 8 minutes of SkiErg at target pace. You learn to produce power with your heart rate already high — the exact skill of the event.
Pure ski volume. 2 × 10 minutes at a sustainable pace, once a week. The SkiErg loads the lats, triceps and trunk in a way no other movement reproduces. If you never do it, your 12 minutes of skiing on race day will be limited by local fatigue, not by your engine.
⚠️ That last point is the most underestimated. An athlete who runs well and has never skied finds out on race day that it's their arms that give out, not their breathing.
What the series tells you that the session doesn't
You've done your three tests, you have your pace. Then what?
Six weeks later, your 3 km has gained thirty seconds. Good news — except your ski distance hasn't moved. Are you improving, or unbalancing yourself?
The answer isn't in a session. It's in the series of sessions.
The ATmetrYX cockpit stacks what the watch sends, and what appears is no longer a distance, it's a curve. When the run curve climbs and the ski curve stays flat, you know where to put the next block's work — without having to guess.
The cockpit installs on your phone like an app. An email, a code, and it's open.
In short
Three things about the 2027 Endurance.
One. The run earns nothing. It buys skiing time, and it's paid for in freshness.
Two. Your optimal pace is found in three sessions, not by reasoning. And it holds for the whole season, since the event doesn't change.
Three. If you've never done SkiErg volume, your arms will decide your score, not your engine.