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Garmin Instinct Solar multisport watch review

Garmin’s latest solar innovation, with a reported 56-day battery life, gets put to the test by James Witts

garmin Instinct Solar multisport watch

Ahhh, the days where your feature-loaded sports watch would struggle to retain power through a race. Bells and whistles capture the attention but, if they’re muffled through limited battery life, they’re deafeningly worthless. The industry has awoken to this and, with the Instinct, it’s reached a new horizon – one that stretches to 56 days.


This length extension is down to the magic of the sun. Solar isn’t new territory for Garmin thanks to the Fenix 6 Pro Solar series. But whereas Garmin’s top-end watch allocated a 1mm display circumference to 100% solar, it’s significantly greater on the Instinct. The result is that 56-day nirvana, although that’s in battery saver mode and training in the sun. Which is where the headlines unravel slightly as this mode results in disabling a number of features, including the optical heart-rate sensor, Bluetooth capability and sleep-tracking options. More practically, you’ll nestle in GPS mode – around 38hrs before recharge – or even GPS Max, which sacrifices accuracy but extends things further.

Apologies if we’ve rambled on about battery life but this is the big sell. And it’s a solid one. But there are caveats. Solar clearly requires the sun, which is inhibited by clouds. But it’s the impact on legibility that’s the biggest loser here, as increasing solar panelling has squeezed the display size. The data’s also lacking the clarity of models like the Fenix or Polar’s Grit. Which is a shame because, as you’d expect from Garmin, it’s brimming with tri-friendly goodness. That HR sensor’s pretty reliable and more efficient than previous versions, while the GPS utilises three different systems for impressive pick-up and accuracy.

It’s the blood-oxygen tracking that’s the standout, however – out of the box anyway. The idea is that a pulse oxygen sensor sends light beams at your wrist to gauge how well you’re absorbing oxygen. In theory, it’s an empirical method to measure how well you’ve acclimatised to higher climes or to detect sleep issues. In practice? The jury’s out.

Standard pulse oximetry devices send wavelengths through the finger and read the results on the other side. The Instinct sends and captures light from the same spot, relying on the reflection of the wavelengths. This reflective method is deemed less accurate, as is taking readings at the wrist compared to the finger. Without access to a lab, we can’t compare results but it’s a noteworthy addition. The Instinct links with Garmin’s great Connect service for deep analysis; it measures altitude; and it’s bulletproof, built to ‘US military standard for thermal, shock and water resistance’. All in, a solid watch but Garmin’s Forerunner devices are arguably better for triathletes.


Verdict: Packed with tech,  but there are better tri watches at this price, 77%