A lactate meter is a medical device used to measure the lactate level in a blood sample. This level provides information about the degree of anaerobic metabolism, which can indicate exercise, stress, illness, or oxygen deficiency in cells. The lactate meter works by placing a small blood sample on a test strip, which is inserted into the device. The device analyzes the sample and quickly displays the lactate level on a digital screen. This measurement is useful in fitness, sports medicine, critical care, and other medical applications to assess an individual's health status and performance.