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Illustration of a person sitting in the dark facing a large glowing screen that shows a dusk landscape — watching a device for a forecast.

Can a smartwatch predict a migraine? What the data actually shows

Illustration of a person's silhouette in a pink-violet dusk landscape with a small point of light glowing just above the head — an attack beginning before anything else has happened.

Your migraine trigger might be the migraine already starting

Illustration of a figure standing in blue mist, one hand at the head and neck, backlit by a pale glowing halo.

Neck pain before a migraine: trigger or symptom?

Wrist temperature on Apple Watch: what the number actually measures

Post-exertional malaise: what PEM is, and why the crash arrives days after the effort

Energy-Limiting Conditions (ELC)

How accurate is Apple Watch calorie tracking, and why heart rate is a different story

Activity tracking

Oura Ring vs Apple Watch: what the accuracy data shows, and whether you need a ring at all

How to improve VO2 max: the training that works, and how long it takes

What is a good VO2 max? What the number means, by age and sex

Welltory promo code: what the app costs, what stays free forever, and 20–36% off for readers

Spoon theory explained: what the spoons really measure, and where the metaphor runs out

Energy-Limiting Conditions (ELC)

Body battery explained: what Garmin's score measures, and how to read your own energy