GPS watches for ultras: battery, navigation, and race-day setup
If your watch dies at mile 70, it becomes dead weight. This page focuses on the ultra basics: battery, a reliable track, simple navigation, and a setup you won’t fight with when you’re cooked.
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Related: AC100 Gear · AC100 Shoes · AC100 Guide
Quick picks
Battery-first pick: Garmin Enduro 2
Great when you want long battery life, mapping features, and a watch built for all-day events.
Check price →Battery monster alternative: COROS VERTIX 2S
Strong battery focus and an ultra-friendly approach to long tracking sessions.
Check price →Safety add-on: Garmin inReach Mini 2
Off-grid messaging + SOS. Optional for race day, high value for solo long runs and backcountry adventures.
Check price →What matters most for ultras
- Battery that matches your slowest day: plan for your worst-case finish time, not your best.
- Reliable GPS track: stable recording matters more than fancy stats.
- Navigation you’ll actually use: breadcrumb, back-to-start, and simple course following.
- Readable screen in sun + at night: you need quick glances, not a science project.
Race-day setup checklist
Before the race
- Fully charge watch (and set a reminder for drop bag charging if you do it)
- Turn off features you don’t need (keeps it simple + reduces surprises)
- Confirm GPS mode you’ll use on race day
- Set data screens: time, distance, elapsed, pace (or effort), heart rate if you use it
During the race
- Start activity early so you’re not rushed
- Lock buttons if your watch has that feature
- Keep screens simple so you don’t stare at your wrist
Navigation habits
- If you load a course, test it once on a local run
- Know your “panic button”: backtrack, back-to-start, or course zoom
- Don’t rely on navigation if you haven’t practiced it
Your watch should reduce stress. If it adds stress, simplify your setup.
FAQ
Do I need full maps for AC100?
Nice to have, not required. For most runners, a clean GPS track + basic navigation is enough.
Should I track heart rate?
Only if you already train with it. Race day is not the time to experiment.