Tracking Sleep Cycles: Can Technology Really Help?

Sleep tracking devices and apps have become increasingly popular, with many people wanting to gain insight into their sleep patterns. Sleep trackers can be used to monitor the quantity and quality of sleep, as well as identify sleep problems. While these trackers can collect a lot of information about sleep habits, they do not measure sleep directly. Instead, they often measure periods of inactivity as a way to estimate sleep. Sleep tracking is not for everyone, and some doctors and specialists have warned that it can increase anxiety in people with insomnia. However, for those who are curious about their sleep, there are many options available, including wearable trackers, non-wearable trackers, and apps.

Wearable sleep trackers

There are several factors to consider when choosing a wearable sleep tracker. Firstly, ensure that the tracker and its companion app are compatible with your devices. Look for trackers that provide not just the data but also a comprehensive summary and contextualised information. It is beneficial to select a tracker that uses data from your daily activities and previous night's sleep to make recommendations and adapt its guidance to your habits. Additionally, opt for a lightweight and comfortable design that you can wear during the day and night without noticing it. Some trackers also offer extra features like guided meditations, breathing exercises, bedtime stories, and daily sleep journals.

When it comes to specific products, the Oura Ring is a trendy and stylish option that tracks sleep, stress, activity, heart rate, and your cycle. It is designed to be worn on the pointer finger, with the sensors at the base of your finger. The Gen 3 version offers six different finishes, with pricing starting at $349, and a $6 monthly membership subscription. The Oura Ring 4 is another variation that monitors an extensive range of metrics to evaluate your sleep and daytime activities. The Ultrahuman Ring Air is also notable for its accuracy and valuable advice in the accompanying app. It features a medical-grade temperature sensor, a PPG sensor, and a motion-sensing IMU.

Other notable mentions include the WHOOP sleep tracker, a comfortable wristband that can also be worn with garments like sports bras or compression tops. It monitors heart rate, respiratory rate, blood oxygen levels, and skin temperature, and includes a smart alarm to gently wake you during the ideal sleep cycle phase. The Garmin brand is well-known in the running community, and their watches, such as the Forerunner series, also track sleep. The Apple Watch Series 4 and later can also be used for sleep tracking.

While these trackers can be insightful, it's important to remember that they don't replace medical care. If you have insomnia, sleep apnea, or other sleep disorders, consult a medical professional. Additionally, sleep-tracking wearables can be inaccurate due to their reliance on actigraphy, which measures movement. They may assume you're sleeping when you're still but awake. For medically accurate data, a polysomnography test is recommended.

Non-wearable sleep trackers

Sleep tracking can be useful for increasing awareness of sleep and encouraging healthy sleep behaviour. It can help you establish a routine, which is vital if you want to improve your sleep quality. However, sleep tracking is not for everyone. Several doctors and sleep specialists have warned that tracking your sleep can sometimes increase anxiety about insomnia and do more harm than good.

If you want to try a sleep tracker but don't want to wear a gadget on your wrist or finger, you might want to try a non-wearable sleep tracker. These devices use advanced technology to gather data about your sleep patterns and are usually placed under your mattress or on your nightstand. Here are some of the best non-wearable sleep trackers on the market:

Withings Sleep Tracking Mat

The Withings Sleep Tracking Mat is a thin mat that goes under your mattress. It has pneumatic and sound sensors that measure your heart rate, respiratory rate, movements, snoring, and sleep cycles. The Withings Sleep Mat is powered through a USB cable and must be plugged in. The data can be easily viewed in the free Withings app through its Wi-Fi sync. The app also automatically generates a sleep diary that includes a sleep score for each night.

Google Nest Hub

The Google Nest Hub is a smart home display that doubles as a non-wearable sleep tracker. When placed on your nightstand, the Sleep Sensing mode can track your sleep using motion and sound. Every morning, you can ask it for a detailed summary of your sleep duration, respiratory rate, snoring, and room conditions like light and temperature. The data can also be found within the Google Fit app, which provides helpful tips based on your history.

Sleep Number Climate360

The Sleep Number Climate360 is a smart mattress that can provide detailed information about your sleep cycles, sleep duration, sleep onset and time to wake, heart rate, and snoring.

When choosing a sleep tracker, it's important to consider factors such as tech compatibility, brand reputation, warranty, and return policies. It's also a good idea to read verified reviews from real customers to get a sense of the product's features and usability.

Sleep tracking accuracy

Sleep tracking can be useful for increasing awareness of sleep habits and encouraging healthy sleep behaviour. Sleep trackers can help users establish a routine by going to bed and getting up at regular times. They can also help users remember to wind down before bed.

However, sleep tracking is not for everyone. Some doctors and sleep specialists have warned that tracking sleep can increase anxiety about insomnia and do more harm than good. It is important to listen to your body and not obsess over sleep tracking data.

There are many sleep trackers on the market, with more being released all the time. Sleep trackers vary based on the technology they use and the sensors that monitor sleep. Some trackers are worn on the wrist, while others clip onto a pillow or sit on a bedside table.

Some sleep trackers monitor the user's heart rate, respiratory rate, blood oxygen levels, and skin temperature. Others use sound analysis to track sleep. Some trackers use a combination of motion-sensing IMU (inertial measurement unit), PPG (photoplethysmography) sensors, and medical-grade temperature sensors.

The accuracy of sleep trackers has been called into question. Sleep trackers do not measure sleep directly but instead often measure inactivity as a surrogate for estimating sleep. Most sleep trackers make some guesstimates about how much sleep the user is getting. For exact data about sleep habits, a medical sleep study that monitors brain waves is required. However, sleep trackers can be useful for helping users recognize patterns in their sleep habits.

Some studies have been conducted to validate the accuracy of sleep trackers. One study analysed 11 commercially available sleep trackers, including 5 wearables (Google Pixel Watch, Galaxy Watch 5, Fitbit Sense 2, Apple Watch 8, and Oura Ring 3), 3 nearables (Withings Sleep Tracking Mat, Google Nest Hub), and 3 airables (SleepImage, SleepScore Max, and SleepPhone). The study found that specific sleep trackers showed substantial agreement with polysomnography, indicating their potential application in sleep monitoring, while others were partially consistent with polysomnography. Another study found that consumer sleep-tracking devices perform as well as, or even better than, actigraphy in some cases.

Sleep tracking limitations

Sleep tracking has gained popularity as it enables individuals to monitor and analyze their sleep. However, there are some limitations to consider. Firstly, sleep trackers do not directly measure sleep. Instead, they often estimate sleep by tracking periods of inactivity. This means that the data provided by these devices is not exact and should be taken with a grain of salt. For precise information about your sleep habits, a medical sleep study that monitors brain waves is required.

Secondly, while sleep trackers can provide insights into your sleep patterns, they may not be beneficial for everyone. Some doctors and sleep specialists have cautioned that tracking sleep too closely can increase anxiety about insomnia and do more harm than good. It is important to listen to your body and not obsess over the data provided by sleep trackers. Establishing a healthy sleep routine that works for you is more important than adhering to a specific set of rules.

Thirdly, the performance of sleep trackers has not been comprehensively validated. Limited studies have been conducted to assess the accuracy of widely used consumer sleep trackers (CSTs). While some trackers have been found to provide better estimates of sleep parameters, the inner workings of the algorithms used are often opaque, making it challenging to fully trust the results.

Lastly, the effectiveness of sleep tracking as a behavioral change catalyst for the general population is uncertain. Most studies that include sleep parameters from trackers are conducted within the context of a medical intervention, such as surgery for cancer patients. This limits the ability to draw conclusions about the impact of sleep tracking alone on improving sleep habits in the general population.

Sleep tracking apps

While sleep tracking apps can be valuable tools for self-management of sleep disorders and improving sleep quality, they have limitations and require improvement in terms of quality and content. The current market offerings cannot definitively identify when a user is sleeping or awake, and their accuracy is affected by external factors such as a bedmate's movements. Additionally, the use of varying algorithms in mobile accelerometers raises concerns due to the lack of validation studies.

Despite these limitations, sleep tracking apps can increase awareness of sleep patterns and encourage healthy sleep behaviours. They can assist users in establishing a sleep routine by going to bed and waking up at regular times, as well as incorporating a wind-down period before sleep. However, it's important to note that sleep tracking may not be suitable for everyone, as it can potentially increase anxiety about insomnia and do more harm than good.

When choosing a sleep tracking app, it is essential to consider factors such as tech compatibility, verified reviews, brand reputation, warranty, and return policies. Some popular options include SleepScore, Sleep Cycle, Ultrahuman Ring Air, WHOOP, and Rise Science Sleep Tracker. These apps and devices offer insights into sleep stages, sleep quality, and factors influencing sleep, helping users make informed decisions to optimise their sleep.

Frequently asked questions