When should you worry if someone is late back from ultrarunning?
Lateness scales with distance. On a five or six hour training run, being an hour behind can simply mean the runner slowed down, which ultrarunners do. The warning signs are a live location that has stopped far from any road, a missed check-in they promised, running out of daylight, heat, or running low on water and food. For a race, call the race headquarters first; for a solo training run, call 911 once your agreed call-by time passes.
Judging a long run that is running long
01Agree on checkpoints, not just a finish time
A single finish time for a 30 mile run leaves you in the dark for hours. Ask for rough times at a few points: a trailhead, a water stop, a summit. If they reach the first two on schedule and then go quiet, you know roughly where to look and how long they've been missing.
02Read pace, not just position
Late in a long run, pace drops. A live location creeping forward at walking speed on a climb is normal. Check how long ago the last update came in: a dot that is still updating but has not moved for 30 minutes in the second half of a run, away from an aid point or car, deserves a call. A stale dot in the mountains more often means no signal; compare the time since that update with how far they had left to go.
03Think about fuel, water and weather
Long efforts deplete runners. In heat, a runner who has run out of water can get into trouble quickly. In cold or after dark, a runner who slows to a walk cools down fast. If any of these apply, shorten your patience.
04During a race, contact the race team
Organized ultras track runners at aid stations and usually have a sweep and a medical team. If a runner you're following hasn't reached the next aid station long after their expected time, call race headquarters or the number in the runner guide. If you believe they're hurt and can't reach the race, call 911.
05On a solo run, call 911 at the call-by time
Tell the dispatcher their name and age, the planned route and trailheads, the last point on the live link and the time it was recorded, how long they have been out, what they are wearing, what they carry (headlamp, jacket, water, food), and any medical conditions. Mention how fit and experienced they are; searchers use it to estimate how far they could have gone. Our guide on when to call 911 if someone is overdue has a fuller list.
Related questions
They're an experienced ultrarunner. Why would they need help?
Experience helps with pacing and navigation, but long efforts in remote places bring their own risks: rolled ankles far from a road, stomach problems, heat illness, dehydration and cold after dark. Most late ultrarunners are fine, which is exactly why a clear plan helps you tell the difference.
How can they make my job easier during a long training run?
Ask them to share a live link and set a return time with some slack built in. If they haven't checked in five minutes after it, Holler's server sends you an overdue alert with their last known location, even if their phone app is closed. Updates pause in areas with no signal, so the checkpoint plan still matters.
What should I have ready before they leave?
Their route or GPX file, the trailheads and roads it crosses, what they're wearing, their car, and any medical conditions. Keep your phone charged and loud. The safety contact guide has a short checklist to go through together.
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Sources, checked September 2026: National Park Service: Trip Planning Guide (contact calls authorities if you are not back on time).
More safety answers, or see the safety guides.