Fitbit’s New Charge 5 Details: Starts To Go After Whoop

At Fitbit's annual end of summer announcement event, the company did not announce a Wear OS device (of any type). Though, they did (re)-commit to building one sometime in the future. Instead, they announced the Charge 5. The company says that the Charge devices make up 1 in 3 Fitbit users today, some 40 million Charge devices in total. And the new Charge 5 is very clearly the most graphically advanced unit to date. Gone is the monochrome display, in is a brilliant AMOLED screen instead.

Of course, AMOLED or similar screens on wearable bands and activity trackers is hardly new. Samsung did it 7 years ago. However, most companies have sacrificed battery life for brilliance. But this time around Fitbit says your Charge 5 will continue to get the roughly 7 days of battery life that the Charge 4 gets. Alongside that new screen is ECG functionality as well as stress detection. Essentially we're seeing the Fitbit Sense from a year ago, squished into the body of a wearable band.

However, perhaps the most interesting feature is Fitbit's new Daily Readiness Score. This score is a combination of three components, including your daily activity level, accumulated sleep, and heart rate variability data. While I'll dive into this in more detail down below, this seems fairly targeted at a more consumer-friendly version of what Whoop is attempting to do with their Recovery Score (or Garmin via FirstBeat, with Body Battery).

Finally, note that this is *NOT* a review. That'll come down the road once the unit nears shipping (timelines in the next section). Instead, I just want to briefly cover some of the newness here before I go hands-on.

Here's the simplified round-up of new features or changes coming to the Fitbit Charge 5:

- New AMOLED color touchscreen display
- New display is 2X brighter than Charge 4 display
- Has an always-on display mode
- Adds Daily Readiness score (requires Fitbit Premium)
- Adds workout & recovery recommendations based on daily readiness score
- Adds high and low heart rate notifications (outside of workouts)
- Adds EDA (Electrodermal Activity) measurement for stress tracking
- Adds ECG sensors/functionality (not available at launch)
- Adding AFIB detection, PDF export for doctors (not available at launch)
- Adding Snoring & Sleep Noise Detection Tracking (later this year)
- Battery life claimed at 7 days
- Still has built-in GPS workout tracking
- Still has all the usual Fitbit activity tracking (steps/sleep/24×7 HR/etc)
- Still has sleep score, sleep stages, smart wake alarm (and Premium subscription adds more depth in metrics)
- Price is $179 USD (includes 6-months membership to Fitbit Premium)
- 10% thinner than Charge 4

Of course, some of these items above don't fully cover the extent of the underlying features, for example the Daily Readiness score is a culmination of multiple features, including taking HRV measurement. Which, we'll dive into in the next section.

Finally, as for availability of the Charge 5 - that's a bit fuzzier. Fitbit has only stated "This Fall", which technically means on/after September 21st. I asked for clarification if that was the intent there. Historically speaking Fitbit actually announces their products a week later (closer to Aug 31st or September 1st), and then we usually see them available mid to late September.

Also historically speaking, for the last few years Fitbit launches mostly incomplete products in terms of features advertised. And we see that same thing here as well. Features like the ECG, Snore Tracking, and Noise detection/tracking won't be available at launch - only stating sometime later this year. While Fitbit did a reasonably good job of hitting their stated timelines last year for leftover features, that hasn't been the case in previous years. Point being, if those specific not-at-launch features are critical to you near-term, you might want to hold out a bit until they're available.

With that, let's dive into a few details.

The Daily Readiness Score:

Arguably, the most interesting thing in the Charge 5 isn't the screen. Sure, that'll probably be pretty and all that. But we've had pretty screens in wearables for years. And don't worry, in my full review I'll test things like visibility in bright sunlight, as the Charge 4 screen was useless on a sunny day (Fitbit says is 2x brighter than the Charge 4). And I'll dive into GPS & heart rate accuracy, and all the other things you expect.

But what caught my attention in the Charge 5 is a new 'Daily Readiness Score', which Fitbit is only making available for Fitbit Premium subscribers. This score is aimed at telling you whether or not you're ready to tackle another workout, whether that workout should be harder, or whether you should take more recover. It does this using a slew of data the watch is collecting in three core categories:

Part 1 - Activity Levels: It's looking at your heart rate values over the course of the day, including both workouts and non-workouts, and figuring out how much effort you put out on that day in terms if fitness fatigue.

Part 2 - Sleep: The platform looks at not just your last nights sleep, but weights it with your last three nights sleep. Meaning if you've had a so-so night of sleep last night, but two solid nights prior, you'll get more leniency than if you had three back to back to back crappy nights of sleep.

Part 3 - HRV Score: The unit measures your HRV score during your deep sleep. Historically speaking Fitbit has done HRV measurement over the course of the night, though I've asked for clarity on exactly which portions of the night they calculate the score from (more on why in a second).

With all three of these things put together, you'll get a 'Readiness Score' that's from 0 to 100 each more. The higher the score, the more 'ready' you are. The lower the score, the more recovery you need:

From the Readiness Score tab you can see the three components that make up the score (Activity, Seep, HRV). You can also see your daily readiness scores over time, to see how things are trending.

However, Fitbit then goes a step further, and gives one of two recommendations: An Active Zone Minutes target, or a Recovery target. Active Zone Minutes are what Fitbit refers to as elevated heart rate activities (so ideally a work, but hey, technically some vigorous horizontal shuffling would work too). Whereas a Recovery target would indicate you should take things a bit more chill today.

If you receive a good score that warrants an Active Zone minutes, you'll get recommendations for specific workouts to fill that quota. These can actually come from Fitbit's library of some 200 audio and video workouts:

Whereas if you receive a low score, then you'll get recommended workouts including recovery-focused yoga or stretching (or other non-intense things):

Fitbit says that "Daily Readiness will be available in the Fitbit app for Premium members with Fitbit Sense, Versa 3, Versa 2, Charge 5, Luxe and Inspire 2
devices" - in other words, it's not just the Fitbit Charge 5 that's getting it.

So, a few thoughts on this, again, at a high level until I start digging into it hands-on:

A) Pulling it together: One of the biggest critiques I made of last year's Fitbit Sense in my review, was that it provides all sorts of sensor data, but absolutely zero meaningful recommendations on what to do with that data. It's a criticism that almost every reviewer echoed. It was as if Fitbit just threw all these health metrics at the wall and said "There, now you have it!". Thus, this Daily Readiness Score seems targeted at fixing exactly that, and doing so in what is a typical easy to understand Fitbit way. That's a huge shift.

B) Clearly Aimed at Whoop: The most obvious take-away here is that this score directly targets what's 'Recovery Score'. Whoop essentially has two core metrics (daily numbers it gives you): Strain & Recovery. Strain is basically your heart-rate driven training load. And Recovery is how recovered you are. But in Whoop's case, Recovery is based on a single 5-minute HRV value taken during your last deep sleep phase. And as any Whoop user can tell you, that's fraught with potential for error. Having so much reliance on a single HRV value from a notoriously poor optical HR sensor means you can have stunning sleep, but if the couple mins it decides it take the reading are wonky, then you'll get a bad score. Also, Whoop *ONLY* looks at the HRV score for recovery. It doesn't care what you did that day, or the previous nights sleep. Fitbit's approach seems to address all those issues (on paper, anyway).

C) Stress Inclusion? It doesn't appear as though stress is accounted for directly within the Daily Readiness Score. No part of any of the documents or presentations that I received calls out inclusion of that within Daily Readiness. While a high heart rate can be seen from stress, that's definitely not a guarantee at all. Keeping in mind that Fitbit put their EDA sensor inside the Charge 5 (from last year's Sense), which is used for stress detection. So it'll be interesting to get more clarity if that's contributing anywhere here.

Now of course, there are other players doing semi-similar things. Just with less clarity. Many people try and compare Garmin's Body Battery to Whoop's platform. And at a high level you can do that, but both platforms are considerably different in how they surface the data to you. I've long said that if Whoop's best asset is the way it visualizes and surfaces the data in their app. It's really damn good at that. Unfortunately, their optical sensor is really damn bad, and thus, all of the insights surfaced to you are largely flawed (again, merely look at the 341+ comments on my Whoop review to see that's the case for virtually everyone).

Whereas Garmin has a far more accurate optical HR sensor, and more accurately breaks down training load on a day by day basis - as well as the impact of that on your recovery. But Garmin's app and platform doesn't prioritize any of that in even remotely the same way as Whoop's. For example, Garmin will give you a recovery time after a workout (based on hours). Then you have training load (on both a per workout basis, and weekly load). Then you have Body Battery (which is essentially a daily score, but impacted by your activity, stress, and sleep). The problem is, that Recovery Hours and Body Battery can and do conflict, because they're somewhat different things. And none of these are pulled together in anything like Whoop's single-page dashboards. Or for that matter, Fitbit's new dashboard.

(Whoop's daily dashboard at left, Garmin's 'My Day' dashboard at right)

So while Garmin's underlying data metrics are far more advanced than Whoop's, and it's individual component recommendations more detailed than Whoops, they're spread amongst half a dozen data pages and menus deep in their app or watch. They stop short of really pulling it all together, unless you get an exceptionally low sleep score, which then triggers a no-workout warning.

Of course, Fitbit distills a lot of this down to the single score with its three components. You won't get the depth of visibility into contributions that you would from Garmin or Whoop. But it's still equally as actionable: Are you going to workout hard today, or are you going to recover today? And to what extent on either. At the one-pager level, it's the same as Whoop. Just delivered in prettier colors (and with less reliance on a single sensor point).

Now, as always, we'll have to see how things turn out in real-life. But we know this underlying optical HR sensor. After all, the Daily Readiness Score works on the Fitbit Sense and Fitbit Versa, and as a result, we've got a pretty good idea how the sensor works, how it performance, and perhaps most notably: The fact that it's 100% of the score in Fitbit's case. That's because Fitbit is looking at sleep/sleep quality, which isn't reliant on the heart rate sensor. As a result, they're more diversified in their approach.

In any case - it's all things for my full review down the line.

Wrap-Up:

There's no doubt that the Charge 5 is a substantially different piece of hardware than the Charge 4 - one only need to visibly look at that to see it. And how all those things perform will be important. If we look back at last year, the other main criticism that reviewers levied against Fitbit was that at launch it was just buggy. Given this is such a substantial platform shift (new display type) for Fitbit, it'll be interesting to see if its a more polished experience. Ideally, they're using much of the same code from the Fitbit Versa 3 & Sense, just with a different display form factor.

But beyond that, I'm more curious in the Daily Readiness Score, and specifically, how each of those three components impact it. And then from there, how it compares with both other units on the market, but also just the reality of how I feel. For all the numbers in the world, most times people know whether they feel recovered or not. And they tend to know whether they're ready for a hard workout. Having a device that either matches that, or can provide a good and accurate data-based reason why you shouldn't trust your instincts is useful. And those are all things I'll be digging into in my full in-depth review.

With that - thanks for reading!

(Nitpickers Corner: Yes, Polar has many recovery and load features. And Suunto has a chunk too. And Polar's workout recommendation bits is quite good in this area. But the overwhelming majority of interest I see is people asking for clarity between what Whoop & Garmin are doing with respect to load/recovery, and thus for today's post, to keep it from getting crazy long, I'm just focusing on this trio.)