Handheld GPS for ultras

My route to ultra running was via hill walking and fell running. GPS units were available in the early 2000s for hill walking, and I had a Garmin Vista Hcx from about 2008, but they are usually against the rules for fell races. In any case, I learned to navigate in the scouts 35 years ago using map and compass.

In most ultramarathons though GPS units of some sort are the norm, and if you insist (as I initially did) on sticking to paper navigation you're putting yourself at a disadvantage. For most of my training I use a map and local knowledge, 

In races most people use the navigation options of their GPS watches, but I find that for the extra couple of hundred grams carrying a handheld GPS unit saves me a lot of bother. I can see at a glance whether I'm on the track, but also zoom out to see the context of the area around me, where the track is going to go next, and even the shape of the landscape nearby and any navigation features.

The unit I use is a Garmin eTrex 20x. That's been obsoleted now by the 22x, which has a lot more memory. If I was looking for one now I'd probably go with the 32x, just because the option to connect via bluetooth to a heart rate monitor would give me a bit more flexibility for what device to use. I'll come to that in a moment.

The red line across the bottom of the map is the route I'm following, and the black arrow is my position on it. Speed and distance remaining at the top.

I still wear a GPS watch - a Suunto Ambit 3 Peak. The navigation features on that are fairly primitive, which makes a difference to my choice of device, but the handheld still has the following advantages:

• secondary device. If one device packs up I still have the other. On one occasion I accidentally paused my watch during a race when taking a mid layer off, and didn't notice for 10km. I was able to get an intact GPS trace of my route from the handheld later.
• I can have my choice of display fields on my watch so I know my pace, distance covered etc.
• AA batteries. If my watch runs out of charge (which is starting to become a possibility as I look at longer races) the handheld lasts a lot longer, and the batteries are easily replaced mid race without having to restart the GPS recording. The 20x records to GPX continuously (although you can switch this off if you prefer).

The handheld has the following advantages over an app on a phone:

• recording the GPX trace (as above)
• It's much tougher. In the 2020 Spire I dropped it in a puddle then fell on it. Not even a scratch.
• the controls are buttons not a touch screen. Easier and faster to zoom in and out, and a lot easier in the rain
• batteries (as above)
• the phone battery isn't depleted by screen/navigation use, leaving it available in case of emergency

You can just about see the speed/distance display at the top of the map

 With some customisation, it's actually just about usable as a replacement for the sports watch. I've switched off most of the menu options and tweaked it so that I toggle between 'dashboard'. and map view by hitting the 'back' button. I've also added 'speed' and 'distance to destination' to the map view. The only problem is that at the start of a race you have to 'delete current track/totals' rather than 'start activity' which is slightly more fiddly and a bit less precise. This is also where integration with a HRM comes in, I'd actually be tempted to use a HR strap with a handheld for very long races, rather than coupling the HR strap to my watch. That reliability of being able to replace AA batteries makes it feel like it'd be a more dependable way of keeping records.

The 'dashboard' view contains a lot more information (and is customisable)

Disadvantages:

• The design of the battery cover to fit into a bracket makes it thicker than it needs to be.
• no 'one click start'
• customisation is a bit fiddly

Maps

The standard map that comes with the Garmin is Garmin's own 'Topo' map. This is basically an OpenStreetMap with shading for height. I found the shading pretty unhelpful, so I replaced it with a Talky Toaster OSM map with contours.

The right of way information on the OSM isn't 100% accurate, so I wouldn't want to rely on it for working out routes, but it's fine to follow existing tracks.

Alternatively for about 200 quid you can get 1:50 OS maps on an SD card.

References:

TalkyToaster maps - https://talkytoaster.me.uk

These are well curated maps with a good choice of detail for walking and running. The source data comes from the Open Streetmap project, an open source mapping project.

Customising and configuring menus on the eTrex series:

http://www.aukadia.net/gps/lw3_4.htm

This site generally has a tonne of useful stuff for the Garmin handhelds.