How to Use It

Getting Started

Masimo provides this step-by-step user guide to assist you in the use of the MightySat device:

Set up

  • Download the free Masimo Personal Health App on the App Store or Google Play
  • Follow the App instructions to sync your MightySat with your smart device

Listen to your body by quickly and accurately measuring key physiologic variables

  • Place the MightySat on your ring finger and wait for the numbers to appear on the display
  • Tap the square below the screen to rotate the display for your optimal viewing angle
  • Take note of your measurements:

Oxygen Saturation (SpO2)
A measure of the oxygen saturation level in your arteries. Higher oxygen saturation indicates more oxygen in the arterial blood. Oxygen saturation can change due to a number of factors, including lung or heart function and altitude.

Pulse Rate (PR)
The number of time your heart pulses, or beats, per minute. This parameter is useful for assessing overall fitness as well as exertion levels at a particular moment in time.


Perfusion Index (Pi)

Pi is the ratio of the pulsing blood to non-pulsing blood flow in your finger and is used to indicate the strength of blood flow to your finger.

Monitoring your body

Learn from your body by monitoring yourself in the morning, after exercise, or anytime you want to know what your body is telling you

Morning monitoring
  • Keep your MightySat at your bedside and each morning
  • Monitor yourself before you get out of bed
  • Establish your normal, or “baseline” values
  • Oxygen saturation (SpO2)
    • A fully oxygenated body generally means a fully recovered and ready body. An SpO2 between 97 and 100% means your body is ready!
    • Note: At higher elevation starting at about 3,000 feet, it is normal for your SpO2to be 3 to 5% lower. The higher elevation you go, the lower your SpO2 will be.
  • Pulse Rate (PR)
    • Your pulse rate changes constantly to provide the necessary blood flow to deliver the oxygen your body needs. Generally, a lower resting pulse rate (40 to 60 beats per minute) means your body is performing more effectively and efficiently.
  • Perfusion Index (Pi)
    • Your perfusion index changes based on whether the blood flow to your body is going up or down, and whether the arteries in your fingers are narrowing (causing your fingers to feel colder) or widening (causing your fingers to feel warmer). There is no specific “normal” value for perfusion index, each person should establish their own baseline value and note how it changes over time. A higher perfusion index means greater blood flow to the finger and a lower perfusion index means lower blood flow to the finger. Your perfusion index may or may not change significantly in the morning or after exercise. Note any changes to your perfusion index and whether you feel any differently when your perfusion index is lower.

After exercise monitoring

  • Keep your MightySat with you when you exercise
  • Immediately after exercise, measure how long it takes for your measurements to change
  • Oxygen saturation (SpO2)
    • Measure how long it takes for your oxygen saturation to return to your baseline value (example, from 95% to 98%).
  • Pulse Rate (PR)
    • Measure how long it takes for your pulse rate to go down by 20 beats per minute (example, from 160 to 140 beats per minute).

Live at your best by tracking and trending your data to make adjustments in exercise, diet, or rest/relaxation

Morning monitoring
  • Oxygen saturation (SpO2)
    • If your oxygen saturation drops more than 3% from baseline, or if it is below 96%, this may be an indication that you need more rest and recovery
  • Pulse Rate (PR)
    • If your resting pulse rate is 10 beats per minute higher than normal, this may be an indication that you are dehydrated, stressed, or fatigued. This may be an indication that you need to rehydrate, relax, or skip intense workouts.
After exercise monitoring
  • Oxygen saturation (SpO2)
    • If your oxygen saturation takes longer to return to your baseline value, this may be an indication that you need more rest and recovery.
  • Pulse Rate (PR)
    • If your pulse rate takes longer than usual to fall by 20 beats per minute, this may be an indication that you need:
      • To rehydrate
      • Give yourself more rest and recovery
      • Change your workout regimen, as you may have hit a plateau and may need a different type of workout to make progress (example, if you have been doing all aerobic training at moderate pulse rate levels, you may need to consider more interval training at higher pulse rate levels to improve your recovery time).

How Others Use It

Dotsie Bausch

Olympic Silver Medalist

Michi Weiss

Olympian and Ironman Champion

Johnathan Edwards

MightySatTM Pulse Oximeter Protocol

Patrick Dixon

Assistant Athletics Director

PLCO-001100/PLM-10813A-0717