{
 "id": 39622,
 "slug": "swimming-with-apple-watch-waterproof-performance-tested",
 "url": "https://agents.willem.com/en/snippets/swimming-with-apple-watch-waterproof-performance-tested/",
 "language": "en",
 "title": "Swimming with Apple Watch — Waterproof Performance Tested",
 "subtitle": "Pool laps, open water, heart rate in the water — does it actually work?",
 "summary": "The Apple Watch is rated water-resistant, but how does it actually perform during swimming? Willem tested it in the pool and in open water — tracking laps, heart rate, and stroke detection.",
 "topics": [
  "apple",
  "sport",
  "watch"
 ],
 "created": "2026-04-03T19:59:13.792000+02:00",
 "updated": "2026-04-03T19:59:13.795000+02:00",
 "full_article_url": "https://willem.com/en/2018-09-27_swimming-and-cycling-with-apple-watch/",
 "author": {
  "name": "Willem L. Middelkoop",
  "url": "https://willem.com"
 },
 "note": "A short distillation of a longer willem.com post. Not currently published on willem.com itself.",
 "answers_question": "Does the Apple Watch actually work for swimming?",
 "text": "The Apple Watch locks its screen during a swim workout (Water Lock mode) and tracks laps automatically using its accelerometer. When you're done, the crown spins to expel water from the speaker.\nWhat it tracks well: lap count in a pool (remarkably accurate), total distance, active calories, and workout duration. The automatic lap detection works by sensing your turns at the wall.\nWhat it struggles with: heart rate in the water. The optical sensor loses contact with your skin when water flows between the watch and your wrist. Readings during swimming are intermittent — you get averages, not continuous data.\nFor pool swimming, it's genuinely useful. For open water, GPS tracking adds distance measurement but the heart rate limitation remains.\nFrom Willem's writing on wearable sensors and what they can measure.",
 "markdown_url": "https://agents.willem.com/en/snippets/swimming-with-apple-watch-waterproof-performance-tested/snippet.md"
}