Running influencer William Goodge has been making headlines after becoming the fastest man to travel across Australia.

He took 35 days to cover 3,800km of terrain, from Perth to Bondi Beach in Sydney.

You can check out the data for his runs over on Strava, but what technology did he actually use to track those runs, which regularly ticked over 100km in a day?

Goodge used both a watch some of you may already own, as well as a tracking device a little more hardcore in order to be compliant with the Guinness World Records rules. Let’s dig into it.

As noted on Goodge’s Strava records, he wore a Coros Vertix 2S as his primary “normal” tracker. This is one of Coros’s top-end watches, and sells for $699.

It’s a good option for one of these ultra-endurance challenges as, unlike many new watches, it has a classic low-power transflective display rather than an AMOLED one. These are “always on” by design and their visibility is only improved by high levels of ambient light, where OLED watches have to use more power to compete with it.

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The Vertix 2S is rated for up to 118 hours of GPS tracking, so even under the gruelling conditions of Goodge’s challenge, it shouldn’t have needed too-regular charges.

While the Coros Vertix 2S would arguably be perfectly up for the job of GPS tracking this challenge, Goodge also took a Garmin InReach tracker with him. This is the Inreach Mini 2, a $399 tracker and emergency satellite communications device.

It was stashed in Goodge’s waist pack, but as it weighs just 100g it shouldn’t have caused too much of a practical issue. It’s this device that mapped out his route on a publicly accessible Garmin webpage.

In his preparatory YouTube video, Goodge claimed it would be set to send a GPS ping every two minutes, rather than the default 10 minutes. This effectively allowed for real-time tracking, while the Coros Vertix 2S data would only be transferred when sync’d with a phone. Like most enthusiast running watches, though, the Vertix records GPS data every second.

Last of all, Goodge also wore a WHOOP tracker, although this is likely because he has some form of sponsorship with the brand. His YouTube videos bear a link to the WHOOP website.

A WHOOP would record additional heart rate results as standard, but such a band is typically used to moderate a fairly intensive workout routine and avoid injury or overtraining. And that doesn’t really apply to someone attempting to run upwards of 110km a day for well over a month.

Despite using legit tech to track his runs, and posting publicly on Strava and the Garmin InReach web portal, Goodge has attracted criticism online, with some suggesting he may have in some way faked the attempt.

Cited evidence includes aberrations in the GPS and pace data, and that Goodge’s heart rate was unrealistically low in long stretches, with some days’ tracking average not too far above 100bpm.

Goodge’s team refutes claims he did not run the full distance, as reported by Canadian Running Magazine last week. Its report is worth a read for more detail on these claims.