How Fitbit Flex 2 Tracks Your Sleep Cycles

Fitbit's Flex 2 is a budget-friendly fitness tracker that offers a wide range of features. One of its key capabilities is sleep tracking, which has been a highly discussed topic among users. The device automatically recognises when you're sleeping and logs your sleep patterns, providing insights into your sleep cycles and quality. However, there have been some discrepancies noted in the accuracy of sleep tracking, with some users reporting delays in recording the onset of sleep. The Flex 2 is also known for its ability to track specific activities, such as steps, swims, and various exercises, making it a versatile option for those seeking a simple yet functional fitness tracker.

The Fitbit Flex 2 can automatically track sleep

The Flex 2 is 30% smaller than the original, making it one of the slimmest fitness trackers available. It is also water-resistant and has a simple design. The tracker can be easily removed from its rubbery classic band and placed in one of Fitbit's premium bangles or pendants. The Flex 2 is comfortable and discreet, making it ideal for those who want to wear it to sleep after using it all day.

The Fitbit Flex 2 automatically recognizes when you’re sleeping and logs your sleep for you. It uses a combination of your movement and heart-rate patterns to estimate your sleep. When you haven’t moved for about an hour, your tracker assumes that you’re asleep. Additional data, such as the length of time your movements are indicative of sleep behavior (such as rolling over), help confirm that you’re asleep.

While you sleep, the device tracks the beat-to-beat changes in your heart rate, known as heart rate variability (HRV), which fluctuate as you transition between light sleep, deep sleep, and REM sleep stages. When you sync your device in the morning, it uses your movement and heart rate patterns to estimate your sleep cycles from the previous night.

It estimates sleep using movement and heart-rate patterns

The Fitbit Flex 2 is a barebones fitness tracker that delivers the essentials, including tracking sleep. It estimates sleep using movement and heart-rate patterns. When the device detects that you haven't moved for about an hour, it assumes that you're asleep. Additional data, such as the length of time your movements are indicative of sleep behaviour (like rolling over), help confirm that you're asleep.

While you're sleeping, the device tracks the beat-to-beat changes in your heart rate, known as heart rate variability (HRV), which fluctuate as you transition between light sleep, deep sleep, and REM sleep stages. When you sync your device in the morning, the Fitbit app uses your movement and heart rate patterns to estimate your sleep cycles from the previous night.

The Fitbit Flex 2 can also be used to track swims as it can be submerged in up to 50 meters of water. This sets it apart from other Fitbit trackers, like the $129.95 Alta and $149.95 Charge 2. It also includes some of Fitbit's more modern features, like the ability to automatically track specific types of exercise.

The Flex 2 is 30% smaller than the original, making it one of the slimmest fitness trackers available. It is also water-resistant and generally comfortable and discreet, making it ideal for those who are looking for a fitness tracker to wear to sleep after using it all day.

It can be worn to bed to track sleep

The Fitbit Flex 2 is a great option for those looking for a fitness tracker to wear to sleep. It is 30% smaller than the original Fitbit Flex, making it one of the slimmest fitness trackers available. Its small size and simple design make it comfortable and discreet to wear while sleeping.

The Flex 2 can automatically track your sleep by recognizing when you're sleeping and logging your sleep duration. It uses a combination of your movement and heart rate patterns to estimate your sleep cycles. When you haven't moved for about an hour, the device assumes you're asleep, and it tracks the beat-to-beat changes in your heart rate, known as heart rate variability (HRV), which fluctuate as you transition between light sleep, deep sleep, and REM sleep stages.

In addition to automatic sleep tracking, the Flex 2 offers the ability to manually start a sleep log from the Fitbit app. This can be useful if you want to track a specific period of sleep or if your Flex 2 fails to detect your sleep automatically. To manually start a sleep log, open the Fitbit app, tap on the Sleep Tile, then on the plus sign in the top right corner, and finally on "Begin Sleep Now" when you're ready for bed.

It's important to note that the Flex 2 might not always accurately detect the start of your sleep. For example, if you're awake and then fall asleep after midnight, the device may record your sleep as starting at 12:15 am instead of the actual time you fell asleep. Additionally, the Flex 2 might have difficulty distinguishing between periods of relaxation or inactivity during the day as sleep, potentially recording them as naps.

It tracks sleep stages and transitions

The Fitbit Flex 2 is a barebones fitness tracker that delivers the essentials, including tracking sleep. It automatically tracks your sleep by using a combination of your movement and heart-rate patterns. When you haven't moved for about an hour, your tracker or watch assumes that you're asleep. Additional data—such as the length of time your movements are indicative of sleep behaviour (such as rolling over)—help confirm that you're asleep. While you're sleeping, your device tracks the beat-to-beat changes in your heart rate, known as heart rate variability (HRV), which fluctuate as you transition between light sleep, deep sleep, and REM sleep stages. When you sync your device in the morning, your movement and heart rate patterns are used to estimate your sleep cycles from the previous night.

The Flex 2's automatic sleep tracking feature means there's no need to tap your tracker before you go to bed. However, it's important to note that the Flex 2 only provides Sleep Stages for a regular night's sleep. It won't provide sleep insights for shorter periods of sleep, such as naps, or if you lie down to rest without sleeping.

The Flex 2 is a small and discreet fitness tracker that is comfortable to wear while sleeping. It is 30% smaller than the original Fitbit Flex, making it one of the slimmest fitness trackers available. The tracker can be easily removed from its classic rubbery band and placed in a premium bangle or pendant, offering a more stylish option for those who want to wear it to sleep.

The Flex 2's sleep tracking feature is a useful tool for those who want to understand their sleep patterns and make adjustments to improve their sleep quality. By tracking your sleep cycles, the device can provide insights into your sleep behaviour and help you identify areas for improvement. For example, if you find that you're not getting enough deep sleep, you can try to make changes to your sleep environment or pre-sleep routine to promote a more restful night's sleep.

In addition to sleep tracking, the Flex 2 offers other basic health-tracking features, such as step counting, calorie tracking, and exercise recognition. It also includes hourly reminders to encourage you to move towards your daily activity goals. For those seeking a simple and inexpensive way to track their sleep and fitness, the Fitbit Flex 2 is a good option.

It's a budget-friendly fitness tracker

The Fitbit Flex 2 is a budget-friendly fitness tracker, retailing at \$99.95. It is 30% smaller than the original Fitbit Flex, making it one of the slimmest fitness trackers on the market. Its small size and simple design make it discreet and comfortable to wear, even at night. The Flex 2 is also water-resistant and can be submerged in up to 50 meters of water, making it suitable for swim tracking.

The Flex 2 offers all the essential features of a basic fitness tracker, including step tracking, calorie counting, and monitoring active minutes and sleep. It also has automatic exercise recognition, a feature called SmartTrack, which lets you track walks, runs, outdoor cycling, sports, aerobic workouts, and swimming without needing to open the app. The Flex 2 can be paired with the Fitbit app, which allows users to see their daily progress, including steps, distance travelled, sleep, and calories burned. The app also allows users to manually enter their food and water consumed and their weight for a more comprehensive overview of their health.

While the Flex 2 does not have a screen, it uses a series of illuminated dots to indicate alerts and daily progress. It also has a vibration motor for alerts. The Flex 2 is easily customisable and can be paired with Fitbit's premium bangles, pendants, or classic bands, which are sold separately.

Overall, the Fitbit Flex 2 is a great option for those seeking a budget-friendly, discreet, and customisable fitness tracker with essential features and automatic exercise recognition. However, for those seeking more advanced features and a screen, it may be worth considering other options or spending a little extra for additional features.

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