How to Use a Pulse Oximeter for Health and Fitness

A pulse oximeter is a helpful tool for assessing lung function and blood oxygen saturation. Your blood carries life-sustaining oxygen to your organs and tissues, and without the proper amounts of oxygen, you could experience a variety of mild to severe symptoms. Fortunately, most people aren’t at risk for developing low blood oxygen levels, but certain lung and heart diseases could increase your risk.See Disclosure ¹ But condition management isn’t the only reason you might want to use a pulse oximeter. You can also use your oxygen monitor for fitness training and high-altitude activities like hiking and aviation.

So how exactly does a pulse oximeter work? Oxygen monitors are often small, reusable devices that attach painlessly to your finger, forehead, nose, ear or toe. Fingertip pulse oximeters are often the most common design, but you may want to explore other styles to find the best oximeter for your body. Like a heart rate monitor, a pulse oximeter doesn’t require any painful needle pricks. Instead, it uses a cold light source to determine heart rate and the percentage of oxygen in red blood cells.

When you read oximeters, you’ll likely see two numbers displayed on your device: Sp0₂ corresponds to your oxygen levels, and PR/bpm relates to your resting heart rate. Pulse oximeter results can vary depending on several factors, including tobacco use and fingernail length, so they should not be used to diagnose a condition. If you’re concerned about your blood oxygen saturation, be sure to consult with your physician to ensure your physical health and safety.

When you visit the doctor’s office, they may use a pulse oximeter to check your blood oxygen levels during an appointment. But for individuals with chronic lung or heart issues, your physician may recommend investing in an at-home oximeter for regular health monitoring and testing. If not provided, be sure to ask your health care provider for recommendations on how often you should check your blood oxygen levels.

Here are some quick tips for using a pulse oximeter at home:

• For fingertip pulse oximeters, ensure your hand is warm and positioned below your heart during the reading.
• Sit still until the oxygen reader has finished adjusting and displays one consistent number.
• Be sure to record your oxygen readings (with dates and times), so you can track any changes that you may want to discuss with your doctor.

If you have a health condition that affects your heart or lungs, such as cardiovascular disease, COPD, anemia, lung cancer, asthma, or pneumonia, an at-home pulse oximeter can be vital for condition management.See Disclosure ² But it’s also important to pay attention to signs and symptoms that may require you to visit your doctor or seek immediate medical attention. If you notice symptoms of low oxygen levels, like shortness of breath, chest pain, racing pulse, or blue coloring on your face, lips or nails, it’s essential you check in with your health care provider right away. But keep in mind that it is possible to experience low blood oxygen levels with no symptoms at all.See Disclosure ³

So what exactly is a low blood oxygen level?

Typically, your blood oxygen levels (Sp0₂) should be between 95% and 100%. However, some lung conditions may cause your normal levels to be a bit lower. If that’s the case, your doctor can help you determine what percentage of saturation is safe for your condition. It’s also important to note that pulse oximeters produce saturation estimates, so your numbers could be about 2% to 4% lower or higher than your actual level. But, for most people, if your Sp0₂ drops below 95%, you’ll need to be seen by a health care professional.See Disclosure ³

Oxygen saturation monitors aren’t solely used for medical conditions. Some people find them helpful for monitoring oxygen levels during exercise and high-altitude activities. You can even find fitness trackers with built-in oximeter sensors, so you can measure other metrics at the same time, like breathing rate, heart rate, activity duration and more.

Studies have shown that some athletes experience decreases in oxygen saturation during high-intensity exercise.See Disclosure ⁴ Depending on your fitness level and activity intensity, it’s not uncommon to see a drop in your oxygen saturation at the beginning or end of a challenging workout. Researchers have observed this effect specifically with aerobic or cardio exercise.See Disclosure ⁵ Adding a pulse oximeter to your workout routine can allow you to check in on your oxygen levels and may become an important aspect of fitness training and workout recovery.

If you’re planning on exploring or exercising in high-altitude settings, a pulse oximeter is a smart tool to bring along. As you climb higher above sea level, the atmospheric pressure and available oxygen in the air naturally decrease.See Disclosure ⁶ This means that if you’re a pilot, planning on climbing Mount Kilimanjaro, or visiting any other high-altitude location, a pulse oximeter can help you monitor your oxygen levels to potentially avoid illness or a medical issue.

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