How to Read the Vital Graph

This graph visualizes how your heart rate changed during each phase of the sauna, cold plunge, and rest. By comparing it with your feeling of totonoi, it can serve as a guide to finding the best routine for you.

💡 The graph display was updated in the April 2026 update!
Since you can now view information other than heart rate, we have renamed it the "Vital Graph."

1. Vertical & Horizontal Axes (Basic Indicators)

• Horizontal axis: Number of Sets (one loop of sauna → cold plunge → rest)

  Instead of time, it is displayed as the flow of each Set.

• Vertical axis: Heart rate (bpm)
  This shows how many times your heart beat in one minute.

2. Legend (Meaning of Colors & Lines)

2.1 Sauna (Red)

This is the phase where your body warms up and your heart rate gradually rises.

• 🙆‍♂️ Good Condition
  It is excellent if your heart rate is rising gradually ◎
• 🙅‍♀️ Bad Condition
  Rising too much or not enough might be due to your physical condition or the environment

💡 Tips for finding your way to totonoi

• Is your heart rate rising too sharply?
• Can you see the effects of your physical condition, such as a slower rise on tired days?
• Did the margin of increase not become too small even as the Sets progressed?

2.2 Cold Plunge (Blue)

The phase where your heart rate drops rapidly due to the cold stimulation

• 🙆‍♂️ Good condition

  Is your heart rate dropping quickly?

• 🙅‍♀️ Bad condition

  If it is slow to drop, it may be due to tension or insufficient cooling.

💡 Hints for exploring how to totonoi

• Did your heart rate drop suddenly right after entering the water?
• Did your heart rate fluctuate in a jagged pattern because it was too cold?
• When your heart rate was slow to drop, was it affected by water temperature or tension?

2.3 Rest (Green)

A relaxing time where your heart rate slowly calms down.

• 🙆‍♂️ Good condition
  The more your heart rate calms down, the more relaxed you are.
• 🙅‍♀️ Bad condition
  If it does not drop fully, you may not have enough rest time, or you may be fatigued.

💡 Hints for exploring how to totonoi

• Did your heart rate continue to drop smoothly during the rest?
• Did it remain high without dropping?
• What kind of heart rate patterns did you see when you felt you reached a state of totonoi?

3. Guidelines (Reference Lines)

• Resting Heart Rate (Purple Dotted Line)
  Your heart rate when you are relaxed. This is based on the value registered in your Profile.
• Target Sauna Heart Rate (Red Dotted Line)
  A guide for when strain on the heart begins. It is one indicator for safely taking a sauna.
  Use the upper area as a guide when you are in good condition, and the lower area when you are not feeling well.
  * This is only a guide, so please prioritize your physical condition and personal feelings of the day.)

💡 Tips for finding your way to totonoi

• If you are unsure how high to raise your heart rate, try aiming for the lower end of the guideline first.
• If you quickly exceed the guideline, we also recommend warming up slowly on the lower bench.

4. Skin Temperature and Body Movement

4.1 Skin Temperature

This indicates how warm the surface of your body is, serving as a guide for how your body is reacting to the heat.

4.2 Body Movement

This shows your level of calmness and changes in physical load based on the amount of body movement, serving as a guide for how comfortably your body is coping.

5. Vital Graph Viewer (Premium Plan)

With the Premium Plan, you can display vital data such as heart rate, body movement, and skin temperature in a full view.

Since it can be zoomed in and out, it makes it easier to visually grasp finer changes and trends.
You can also export the graph itself as an image.

sauna device 3 features a highly precise heart rate sensor, enabling the detection of minute heart rate fluctuations caused by breathing and other factors.
While normal graphs show a smoothed heart rate for readability, the Vital Graph Viewer allows you to check raw heart rate data indicated by thin, light lines.

💡 When entering the sauna while taking slow, regular deep breaths, beautiful waveforms synced with your breathing may appear in the raw data📈