Deep dive: How exactly the Apple Watch tracks swimming
Measuring motion in the water is complex. This is how Apple’s wearable does it.
By Rob Verger
Last week I splashed into an underground university pool with an Apple Watch Series 3. As the company’s wearable has matured, Apple has marketed it more and more as a fitness device, one that’s, thanks to a partnership with Nike, particularly well-suited as a running companion. But the Apple Watch also tackles something more dynamic and varied than your morning jog: exercise in the water.
The device has functioned as a swim tracker since it became water-resistant in 2016, but with its latest operating system, it presents a more granular metric: set detection. It knows when you rest at the pool’s edge and then uses that information to divide the workout into sets of laps, showing you how far and long you swam in each, what stroke, and your rest time.
You don’t need the latest model Apple Watch to get this information. A Series 2 running the 4th-generation operating system will do just fine. But I swam with the company’s newest version, the one with a cellular connection. I could make a call on my way to the pool without bringing my phone, but that was the biggest advantage the latest and greatest offered.
