The Efficacy and Importance of Pulse Oximetry

Data is the second voice of the athlete. This leveraging of data is a simple way to ensure optimum realization of athletic potential. Using pulse oximetry gives the athlete and coach a look into what’s happening on the inside, namely the cardio-pulmonary system. Pulse oximetry is ubiquitous in medical settings, and yet it is somewhat of a new metric. Before 1970, pulse oximetry was not widely used. Today, it is a common device that anyone can purchase. Analysis of pulse oximetry trends can yield insights into the athlete’s response to a new environment, training technique, recovery modalities, and performance. Only recently have they become available for athletes. For the athlete, oxygen delivery to the tissues is imperative for optimizing performance results. We will be talking about the use of the Masimo Mighty Sat Pulse Oximeter and its unique set of Bio-Markers: SpO2, RR (Respiratory Rate), PR (Heart Rate), PVI (Pleth Variability Index), and PI (Pulse Index).

What is a pulse oximeter? It’s a device that measures the blood oxygen levels (oxygen saturation or Sp02). More specifically, pulse oximetry is a method used to estimate the percentage of oxygen bound to hemoglobin in the blood. This approximation of SaO2 is displayed as SpO2. SaO2 is the saturation of arterial oxygen and SpO2 is the saturation of peripheral capillary oxygen. Pulse oximeters are small, portable, non-invasive and painless. They are often used by pilots and people that work or train at high altitudes. How a finger-pulse oximeter measures blood oxygen is quite simple. We all know that oxygen is inhaled into the lungs, passes into the blood, and then the oxygen attaches itself to hemoglobin (a protein located inside the red blood cells). The red blood cells transport oxygen into the bloodstream and delivers it where needed. Once this occurs, the oxygenated blood circulates and is dispersed to the tissues. Digital pulse oximeter technology utilizes the light absorption properties of hemoglobin and the pulsating nature of blood flow in the arteries to determine oxygen saturation (Sp02). The pulse oximeter emits two different light sources (red and infrared) through the finger and onto a photodetector on the other side. Since the two light sources are absorbed differently by hemoglobin without oxygen (deoxyhemoglobin) and hemoglobin with oxygen (oxyhemoglobin), analysis of the signal allows the oxygen saturation and heart rate to be measured. Normal ranges are typically from 94 percent to 100 percent, although values down to 90 percent are common. The Masimo Might Sat uses 8 different light sources to measure the various Bio Markers (SpO2, HR, RR, PVI, and PI).

SpO2 – Peripheral Saturation of Blood Oxygen

PR – The Heart Rate or the “time interval” between the P and R waves in a heart tracing

RR – The Respiratory Rate as measured by the Masimo Mighty Sat

PVI – Pleth Variability Index, which is a measure of the volume or hydration in the body

PI – Pulse Index or the strength of the pulse detected by the pulse oximeter

Whatever the sport, it becomes increasingly challenging to achieve an optimal workout and stave off the competition. Monitoring the effects of exercise is important as a means of ensuring progress and subsequent success. It can also be the difference of not overtraining and getting better sleep. Often, milli-seconds can be the difference between finishing on or off the top step of the podium. Efficiency. Endurance. Speed. These are common core goals critical to athletes trying to achieve optimization. No matter the sport, race or creed, we all breath oxygen. No matter how much nutrition you take in, none of it matters without oxygen. This has always been the case and it will always be (unless we move to Mars). The way our body uses oxygen is the great equalizer. This may be why you want to consider measuring oxygen. The simplest way to do that is to use a pulse oximeter.

The science of oxygen delivery is complex. We take oxygen for granted, it can’t be seen, we just know it’s there. It’s in the air we breathe, sometimes there is more of less of it depending the altitude. But did you know that oxygen can be measured in volume, just like the glass of water you are drinking from. Most of us use about 550 liters of oxygen per day (no exercise). We can double or triple the volume during exercise. Every bodily function – blood pressure, metabolism, brain and muscle function are all dependent on the lungs ability to deliver oxygen throughout the body. Ensuring that oxygen levels are optimized for a workout or event is something that has only recently become possible. Advancements in science have allowed us to measure oxygen levels before, during and after workouts.

Athletes intuitively know about how much oxygen is being used by the body. Runners know that a constant flow of oxygen must be present to run long endurance events. Cyclists know their oxygen consumption is minimal at a zone 2 pace and maximal at zone 5. Sprinters know that the oxygen in their bodies at the start of the race is very important. Deep divers know exactly how much time it takes to use all the oxygen in their bodies before they have to resurface. But we have only just started using pulse oximeters and other bio-markers to measure how much oxygen we are using for a respective activity.

During periods of high intensity training, there is a tendency for blood oxygen levels to drop. The objective is to keep muscles working harder and longer for extended periods of time. Basic physiology tells us that oxygen-rich muscles will improve overall muscular function and overall performance. It’s much more complex than this, but oxygen is at the center of it all.

Pulse oximeters are valuable training tools. Easy to use and compact, models are now available that comfortably fit around the wrist, are motion resistant and consistently accurate. They don’t interfere with training workouts. In addition, pulse oximeters can be used to evaluate people with compromised lung or heart function. Pulse oximeters are a great way to help athletes unleash their true potential with more effective workouts. These powerful performance-monitoring tools are low cost, easy to use and accurate.

Johnathan Edwards is a medical doctor with 30 years of sport medicine experience. A former professional athlete in the sport of motocross and a Category 1 bicycle racer, Johnathan understands human performance. He obtained a complete Physiology degree from UC Davis, medical school in Norfolk, VA, Internal medicine in Las Vegas, Sports medicine in Utah, and Anesthesiology in Florida. Today he is a performance coach, clinical instructor, team doctor for many cycling teams, UFC, motocross and Olympic athletes. Husband and father, he aspires to live part time in France and the United States, and riding his bike. Full Disclosure – Johnathan is a consultant for Masimo and the Mighty Sat.