{"id":852879,"date":"2026-09-19T04:46:23","date_gmt":"2026-09-19T04:46:23","guid":{"rendered":"https:\/\/www.newsbeep.com\/us\/852879\/"},"modified":"2026-09-19T04:46:23","modified_gmt":"2026-09-19T04:46:23","slug":"the-quantified-scientist-tests-the-apple-watch-series-12s-heart-rate-sensor","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us\/852879\/","title":{"rendered":"The Quantified Scientist tests the Apple Watch Series 12\u2019s heart rate sensor"},"content":{"rendered":"<p>\t<img width=\"1600\" height=\"800\" src=\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/09\/apple-watch-heart.webp\" class=\"skip-lazy wp-post-image\" alt=\"\"  decoding=\"async\" fetchpriority=\"high\"\/><\/p>\n<p class=\"wp-block-paragraph\">In a new video, The Quantified Scientist\u2019s Rob ter Horst compares the new A<a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">pple Watch Series 12<\/a>\u2019s heart rate sensor against a Polar H10 ECG chest strap. Here\u2019s what he found.<\/p>\n<p>Revamped heart sensor delivers<\/p>\n<p class=\"wp-block-paragraph\">For the <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Apple Watch Series 12<\/a>, Apple completely revamped the device\u2019s heart sensor, which now measures heart rate every five seconds even when the user isn\u2019t active.<\/p>\n<p class=\"wp-block-paragraph\">In our review of <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Apple Watch Series 12<\/a>, which you can <a href=\"https:\/\/9to5mac.com\/2026\/09\/17\/apple-watch-series-12-and-ultra-4-review\/\" rel=\"nofollow noopener\" target=\"_blank\">read here<\/a>, we found that the added data can provide more detailed insights into how everyday activities and moments throughout the day affect heart rate, such as hauling groceries, doing yard work, drinking an afternoon cup of coffee, or dealing with a stressful moment at work.<\/p>\n<p class=\"wp-block-paragraph\">That said, Rob ter Horst from The Quantified Scientist YouTube channel published an in-depth look (via <a href=\"https:\/\/macmagazine.com.br\/post\/2026\/09\/17\/apple-watch-series-12-e-mais-preciso-para-medir-a-frequencia-cardiaca-do-que-concorrentes-comprova-teste\/\" rel=\"nofollow noopener\" target=\"_blank\">MacMagazine<\/a>) at the <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Apple Watch Series 12<\/a>\u2019s new heart rate sensor during indoor cycling, running, and weightlifting, and compared its readings with those from a Polar H10 ECG chest strap.<\/p>\n<p class=\"wp-block-paragraph\">All in all, the <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Apple Watch Series 12<\/a>\u2019s new heart sensor performed very well, particularly during indoor cycling, where its readings were nearly identical to the Polar H10 data.<\/p>\n<p class=\"wp-block-paragraph\">During a running session, the <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Series 12<\/a> also performed well, with a 0.98 correlation with the chest strap (versus a near-perfect correlation of 1.0 during indoor cycling), though ter Horst noted some minor deviations at higher heart rates.<\/p>\n<p class=\"wp-block-paragraph\">During weightlifting, which ter Horst notes is traditionally one of the hardest activities for wrist-based heart rate sensors, the <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Series 12<\/a> posted the lowest correlation of the three exercises tested, at 0.97. Even so, ter Horst said the result was \u201cquite good\u201d compared with the competition, placing the Series 12 above 85% of devices he has tested for weightlifting.<\/p>\n<p class=\"wp-block-paragraph\">Compared with his longer-term testing of the Apple Watch Series 11, ter Horst said the new <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Apple Watch Series 12<\/a> delivered broadly similar heart rate accuracy overall, with the older model actually performing slightly better during running in his tests. It could be the case, ter Horst notes, that Apple is still tweaking its algorithms for the new sensor.<\/p>\n<p class=\"wp-block-paragraph\">Finally, ter Horst also tested the <a href=\"https:\/\/amzn.to\/4rkQzN0\" rel=\"nofollow noopener\" target=\"_blank\">Apple Watch Series 12<\/a>\u2019s step counter. He manually counted roughly 5,000 steps and found the Series 12 was generally spot-on or only slightly overcounted.<\/p>\n<p class=\"wp-block-paragraph\">You can watch his full video below:<\/p>\n<\/p>\n<p class=\"wp-block-paragraph\">Once you\u2019re done, make sure you catch <a href=\"https:\/\/9to5mac.com\/2026\/09\/17\/apple-watch-series-12-and-ultra-4-review\/\" rel=\"nofollow noopener\" target=\"_blank\">9to5Mac\u2019s own review<\/a> of the new Apple Watch Series 12.<\/p>\n<p class=\"wp-block-paragraph\">Did you buy the new Apple Watch Series 12? Let us know in the comments.<\/p>\n<p>Worth checking out on Amazon<\/p>\n<p>\t\t<a target=\"_blank\" rel=\"nofollow noopener\" href=\"https:\/\/google.com\/preferences\/source?q=https:\/\/9to5mac.com\" aria-label=\"Add 9to5Mac as a preferred source on Google\"><br \/>\n\t\t\t<img decoding=\"async\" class=\"google-preferred-source-badge-dark\" src=\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/09\/1789793181_462_google-preferred-source-badge-dark.png\" alt=\"Add 9to5Mac as a preferred source on Google\"\/><br \/>\n\t\t\t<img decoding=\"async\" class=\"google-preferred-source-badge-light\" src=\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/09\/1789793182_961_google-preferred-source-badge-light.png\" alt=\"Add 9to5Mac as a preferred source on Google\"\/><br \/>\n\t\t<\/a><\/p>\n<p class=\"disclaimer-affiliate\">FTC: We use income earning auto affiliate links. <a href=\"https:\/\/9to5mac.com\/about\/#affiliate\" rel=\"nofollow noopener\" target=\"_blank\">More.<\/a><\/p>\n<p><a href=\"https:\/\/bit.ly\/4h71BAQ\" rel=\"nofollow noopener\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-1069498\" src=\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/09\/1789793183_434_09-10-iPhone-18-Pro-Ghost-Banner.png\" alt=\"\" width=\"1500\" height=\"300\"\/><\/a>\t\t\t\t<\/p>\n","protected":false},"excerpt":{"rendered":"In a new video, The Quantified Scientist\u2019s Rob ter Horst compares the new Apple Watch Series 12\u2019s heart&hellip;\n","protected":false},"author":2,"featured_media":852880,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[31],"tags":[74],"class_list":["post-852879","post","type-post","status-publish","format-standard","has-post-thumbnail","category-technology","tag-technology"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/852879","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=852879"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/852879\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/852880"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=852879"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=852879"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=852879"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}