Adenosine triphosphate (ATP) is the biochemical way to store and use energy. F or your muscles -- in fact, for every cell in your body -- the source of energy that keeps everything going is called ATP.
An approximate blood oxygen level can also be estimated using a pulse oximeter â a small device that clips on your finger. Though the pulse oximeter actually measures the saturation of oxygen in your blood, the results are often used as an estimate of blood oxygen levels.Normal pulse oximeter readings range from 95 to 100 percent, under most circumstances. Values under 90 percent are considered low.1  Causes.n approximate blood oxygen level can also be estimated using a pulse oximeter â a small device that clips on your finger. Though the pulse oximeter actually measures the saturation of oxygen in your blood, the results are often used as an estimate of blood oxygen levels.
What is pulse oximetry? Pulse oximetry is a noninvasive method that enables the measurement of a personâs blood oxygen saturation, which is often referred to as SpO2 or âThe Fifth Vital Signâ (the first 4 being your pulse, temperature, blood pressure and respiratory rate).hat is pulse oximetry? Pulse oximetry is a noninvasive method that enables the measurement of a personâs blood oxygen saturation, which is often referred to as SpO2 or âThe Fifth Vital Signâ (the first 4 being your pulse, temperature, blood pressure and respiratory rate).