<\/p>\n Despite the Whoop MG being listed as a medical-grade wellness device, the Apple Watch Ultra 2 bested it, along with the rest of the competition, by a notable margin. Ter Horst reports that heart rate data from the Ultra 2 is nearly a perfect match with the H10, with only slight deviations.<\/p>\n You may like<\/p>\n Apple beats Garmin, Samsung and Whoop for heart rate accuracy <\/p>\n \n (Image credit: Future)<\/p>\n The Samsung Galaxy Watch 7, meanwhile, was the second-most accurate wearable he tested, with roughly 3% deviation from the control data. The Whoop MG came in third place with 6% deviation, followed by the Garmin Forerunner 570 with 7% deviation, and lastly, the Garmin Fenix 7 with 9% deviation.<\/p>\n Further testing while running and cycling in an outdoor environment similarly resulted in near-perfect heart rate data from the Apple Watch Ultra 2.<\/p>\n Other wearables did noticeably worse when the testing moved outside. The Forerunner 570 data deviated a troubling 12% from the control, while data from the Whoop MG deviated a whopping 15%.<\/p>\n Apple Watch Ultra 2 + WatchOS 26 – Scientific Review (Still The Best On iOS!) – YouTube Watch On <\/a> \n (Image credit: Future)<\/p>\n In separate testing, ter Hurst also found the Apple Watch Ultra 2 to be a reasonably accurate sleep tracking device, capable of correctly identifying REM and deep sleep 73% of the time and light sleep 86.5% of the time. For this test, he used the Hypnodyne ZMax, a head-mounted sleep monitor, as the control.<\/p>\n While the 73% accuracy may seem a bit low, ter Hurst notes that the opposite is true. In fact, from his testing, the Ultra 2 is a more accurate sleep tracker than most other consumer wellness wearables out there, including the Oura Ring 4<\/a> \u2014 the best smart ring<\/a> available today.<\/p>\n What does this mean for the Ultra 3?<\/p>\n \n (Image credit: Future)<\/p>\n With all this talk of the Apple Watch Ultra 2, you may be thinking to yourself, \u2018What about the Apple Watch Ultra 3?\u2019 Well, dear reader, with an official Apple event on the calendar for September 9th<\/a>, there\u2019s a decent chance that Cupertino\u2019s next-gen, tough-built wearable will grace us with its presence before we know it.<\/p>\n There\u2019s no shortage of Apple Watch Ultra 3 rumors<\/a>, including the possibility of screen upgrades, battery life enhancements, additional safety and wellness tools, and even AI features. As a result, my expectations (and excitement levels) are sky-high.<\/p>\n However, even if the Ultra 3 doesn\u2019t arrive as expected, Cupertino can still sleep soundly resting on the laurels of the Ultra 2\u2019s performance in ter Horst\u2019s testing.<\/p>\n Follow Tom’s Guide on Google News<\/a> to get our up-to-date news, how-tos, and reviews in your feeds. Make sure to click the Follow button.<\/p>\n More from Tom’s Guide<\/p>\n","protected":false},"excerpt":{"rendered":"It wasn\u2019t necessarily the outcome he was expecting when Rob ter Horst, a data scientist at the University…\n","protected":false},"author":3,"featured_media":183320,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18],"tags":[705,158,67,132,68],"class_list":{"0":"post-183319","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-gadgets","8":"tag-gadgets","9":"tag-technology","10":"tag-united-states","11":"tag-unitedstates","12":"tag-us"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/115108982654123952","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/183319","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=183319"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/183319\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/183320"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=183319"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=183319"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=183319"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"Apple](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/08\/J84qpiFRmDyr9o3GhxBpmA.jpg\")
\n<\/p>\n
\n![\"Apple](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/08\/1756423573_735_maxresdefault.jpg\")
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\nThe Ultra 2 is also a darn-accurate sleep-tracker <\/p>\n![\"oura](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/08\/2ekqxUqhPbFnUwWLUUa4EG.jpg\")
\n<\/p>\n![\"Apple](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/08\/vKbb8u8HtXBcL3JvgHdDNF.jpg\")
\n<\/p>\n