Apple is giving its health and fitness features a major upgrade, bringing Apple Intelligence deeper into the Health app while introducing a new Health Sensing System for the Apple Watch Series 12 and Apple Watch Ultra 4.

The changes, announced September 9, are aimed at making Apple Watch and iPhone more useful as everyday health companions. Rather than simply collecting more biometric data, Apple is increasingly trying to interpret that information and turn it into recommendations users can actually act on.

The new Apple Watch Health Sensing System introduces higher-frequency heart-rate and heart-rate variability (HRV) measurements, a new daily Readiness score, expanded Vitals information, and an updated Heart Rate app. Apple also says a study involving more than 1,000 participants found its new heart-rate sensing system had the highest accuracy among the wearables included in the comparison.

Apple Watch gets more frequent health measurements

The Apple Watch Series 12 and Ultra 4 use larger, power-efficient green LEDs in their optical heart sensors to measure heart rate every five seconds throughout the day. Apple says the more frequent measurements can provide a deeper picture of a user’s physiological state while also improving the accuracy of features such as the Exercise and Move rings.

HRV measurements are also getting a significant boost. Apple Watch can now measure HRV as often as every five minutes, which Apple describes as 24 times more frequently than before. The Heart Rate app will show two types of HRV: Recovery HRV, intended to highlight daily signals related to stress and recovery, and overall HRV, which provides broader health information including cardiovascular trends.

The Vitals experience is expanding as well. Overnight Vitals can now include Recovery HRV compared against a user’s personal baseline, while a new daytime view can show changes in metrics that might otherwise only become apparent during overnight measurements.

A new Readiness score tries to answer a simple question

One of the more visible additions is Readiness, a new daily score designed to tell users how prepared their bodies are for the day.

The feature combines recent activity, vitals, and sleep data into a score from 0 to 10. Instead of leaving users to interpret the numbers themselves, Apple Watch translates the result into recommendations such as “Recover,” “Pace Yourself,” “Ready,” or “Go For It.” The score can also change during the day as new information arrives, such as an intense workout or a shift in daytime vitals.

Apple says the Readiness algorithm was developed using data from the Apple Heart and Movement Study in collaboration with exercise scientists and physicians.

That makes the feature particularly interesting because it moves Apple Watch another step away from being a device that simply reports measurements. The goal is to give users a quick interpretation of what those measurements could mean for their day.

Apple Intelligence comes to the Health app

The bigger software change is happening on the iPhone and iPad.

With iOS 27 and iPadOS 27, Apple Intelligence is being integrated into a redesigned Health app. Apple says the app will dynamically adapt to a user’s health and fitness metrics, combining long-term information with more immediate insights and personalized recommendations.

A new Insights tab will provide summaries across areas including heart health, sleep, readiness, fitness, vitals, and cycle tracking. The new For You section can surface recommendations and relevant health information based on a user’s data.

For example, someone experiencing a run of late nights could receive a suggestion related to improving their wind-down routine. The idea is to make the Health app less like a database of disconnected measurements and more like a personalized health dashboard.

Apple is also adding a new Longevity tab that looks at longer-term trends across heart health, sleep, mental wellbeing, movement, metabolic health, hearing, and nutrition.

One of its most notable features is Health Age, which uses Apple Watch data to show how a user’s health metrics are tracking relative to their chronological age. Apple says the system can consider information such as VO2 max, resting heart rate, sleep, and HRV, with users also able to add laboratory information such as A1c and LDL results.

Your iPhone camera can become part of a movement assessment

Apple is also using AI to make physical assessments possible at home.

The redesigned Health app will allow users to perform assessments measuring flexibility, strength, balance, movement mechanics, and VO2 max using an iPhone camera and Apple Watch.

Apple says the experience uses vision-based AI models to provide real-time audio and visual feedback. Importantly, the company says the assessments run entirely on-device, with no video recorded, stored, or shared. The system was developed with input from clinicians.

That could make the iPhone camera a much more active part of Apple’s health ecosystem. Instead of simply recording workouts or acting as a display for Apple Watch data, it can help evaluate how a person moves.

Health data is moving closer to the doctor’s office

Apple is also expanding the role of laboratory data in the Health app.

Users can already import existing lab results, but Apple says they will eventually be able to schedule and purchase new tests through the Health app. The offering will include more than 50 key biomarkers for $119 at approximately 2,000 Quest Diagnostics locations across the U.S.

The company is also planning more personalized health content. After receiving lab results, for example, users could see videos or articles from Apple Health clinical experts explaining what particular measurements mean and what steps might help improve them.

Similarly, if a movement assessment identifies balance as an area for improvement, the Health app can provide educational material and an exercise plan tailored to the user’s abilities and needs.

The redesigned Health app is expected later this year, initially in U.S. English, with additional languages to follow.

Apple expands reproductive and fitness features, too

The health update isn’t limited to AI and heart sensing.

With iOS 27, Cycle Tracking is gaining support for perimenopause and menopause. Users will be able to log their status, track symptoms, and monitor changes over time. People age 40 and older can also receive a notification when changes in logged cycle patterns may be suggestive of perimenopause, giving them an opportunity to discuss the changes with a doctor.

Apple is also expanding Workout Buddy so it can operate directly on Apple Watch without an iPhone nearby. The feature can incorporate additional fitness data when providing motivational feedback and will be available in English and Spanish.

GymKit is getting an upgrade as well. Users with AirPods Pro 3 will be able to send heart-rate information through their iPhone to compatible gym equipment, including treadmills and indoor bikes. Apple is also using new machine-learning models to improve treadmill distance calculations from the beginning of a walk or run.

Apple’s health strategy is becoming more predictive

The most important part of Apple’s announcement isn’t any individual feature. It is the direction the company is taking.

Apple Watch has spent years accumulating increasingly detailed information about heart rate, sleep, activity, workouts, and other aspects of everyday health. Apple is now building a layer of intelligence on top of that data, with the goal of helping users understand what their numbers mean rather than simply displaying them.

The combination of more frequent sensing, Readiness, AI-powered Health app insights, Health Age, movement assessments, and laboratory data gives Apple a much broader health platform than it had a few years ago.

At the same time, Apple is emphasizing that personal health information remains private and under the user’s control. The company says the redesigned Health app was built with security and privacy throughout the experience, while the new camera-based movement assessments run entirely on-device.

The redesigned Health app will arrive later this year on compatible Apple Intelligence-enabled iPhone and iPad models, while the new Health Sensing System arrives with Apple Watch Series 12 and Apple Watch Ultra 4. watchOS 27 itself will be available starting September 14 for Apple Watch Series 9 or later, Apple Watch SE 3, and Apple Watch Ultra 2 or later, although individual features vary by device and region.