Polar has just announced its newest flagship running watch, and the update is right in line with what you might expect for a 2017 health-and-fitness-tracking wearable: it includes wrist-based heart rate sensors.

The new M430, which is the follow-up to Polar’s M400 flagship running watch, has six LED lights for optical heart rate sensing, built-in GPS, and a thinner, lighter build. It looks pretty similar to the previous model — it still has a monochrome display and the same unibody design, which means you can’t swap out straps — but it weighs just 51 grams (1.8 ounces) compared with 56 grams, or two ounces, for the M400. It also has a redesigned perforated strap, for breathability.

Like a lot of new fitness watches, the watch supports smartphone notifications, so you can get alerts directly on your wrist; although like many others in this category, the options for interacting with these notifications are limited. (Polar also ships a smartwatch, the M600, that runs on Android Wear and offers more of this kind of “smart” functionality.)

Polar is emphasizing two aspects of this new M430 watch. The first is its customized algorithms for heart rate. Polar says it tweaks these algorithms for every single new device it puts out on the market, since things like size and weight can impact the pendulum motion of a watch on the wrist.

For what it’s worth: other companies like Garmin and Fitbit say they also fine-tune their algorithms for each new device; but Polar has long been known for its high-quality, accurate heart rate straps, so it has a reputation to uphold when it comes to any kind of heart rate sensing.

The second part, which isn’t specific to the M430 watch, involves Polar’s “Smart Coach” features. These appear both in Polar Flow mobile app and on the watch itself. After completing a run, you immediately see a score called the Running Index on the watch, a mash-up of your length of run, how fast you ran, and how hard you worked out overall. You can get a sense of your aerobic vs. anaerobic activities (something that Garmin just brought to its new multisport Fenix 5), see both your immediate and residual training load, and get free guidance on a running program based on your gender, weight, age, experience, and running time.

The new M430 running watch starts shipping in May and will cost $229.