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Suunto 3 Fitness User Guide

Sleep tracking

A good night's sleep is important for a healthy mind and body. You can use your watch to track your sleep and follow how much sleep you are getting and how well you are sleeping.

When you wear your watch to bed, Suunto 3 Fitness tracks your sleep based on accelerometer data.

To track sleep:

  1. Go to your watch settings, scroll down to Sleep and press the middle button.
  2. Toggle on Sleep tracking.

    sleeptracking setting Trainer

  3. Set the times for going to bed and waking up according to your normal sleep schedule.

The last step defines your bedtime. Your watch uses that period to determine when you are sleeping (during your bedtime) and reporting all sleep as one session. If you get up for a drink of water during the night, for example, your watch still counts any sleep after that as the same session.

If you fall asleep earlier, or sleep longer, than your set bedtime, your watch will track your sleep as long as a part of your sleep is in within your set bedtime and wake up time.


If you go to bed far outside of your bedtime, the watch may not count that to your sleep session.

Once you have enabled sleep tracking, you can also set your sleep target. A typical adult needs between 7 and 9 hours of sleep per day, though your ideal amount of sleep may vary from the norms.


All sleep measurements, except for sleep quality and average HR, are based on movement only, so they are estimates that may not reflect your actual sleep habits.

Sleep quality

In addition to duration, your watch can also assess sleep quality by following your heart rate variability during sleep. The variation is an indication of how well your sleep is helping you rest and recover. Sleep quality is shown on scale from 0 to 100 in the sleep summary, with 100 being the best quality.

Measuring heart rate while sleeping

To get sleep quality measured, ensure that Daily HR (see Daily HR) and sleep tracking are enabled.

Automatic Do Not Disturb mode

You can use the auto Do Not Disturb setting to automatically enable Do Not Disturb mode while you sleep.

Sleep trends

When you wake up, you are greeted with a summary of your sleep. The summary includes the total duration of your sleep, as well as the estimated time you were awake (moving around), when you went to bed, when you woke up and your average HR sleep quality.

You can follow your overall sleep trend with the sleep insight. From the watch face, press the lower right button until you see the Sleep duration display. The first view shows your last sleep compared to your sleep duration target.

SF3 Sleep Last Night

While in the sleep display you can press the middle button once to view your average sleep duration and then your average heart rate while sleeping over the last seven days. The data can be viewed as numbers instead of graphs by pressing the lower right button.


From the Sleep display, you can keep the middle button pressed to access sleep tracking settings and the latest sleep summary.

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