Image taken from an article by Oana Milton defining each individual component as posted on https://benchesreview.com/fitness-components/
The Pacer is a multi-stage cardio-vascular endurance test that gets faster each minute and tests one's aerobic capacity utilizing VO2max. To explain it basically, it gets increasingly more difficult over time and really tests an individual's lung and heart health. capacity. The test is used by sporting organizations including U.S. Soccer and several NHL hockey teams, along with schools (colleges and high schools), the U.S. military, and others interested in gauging cardiovascular endurance. Although specifically a test, it can also be used to increase endurance as it tends to get easier, like any running, the more you do it. Because it's so difficult, people who are long distance runners tend to be able to "pace" themselves better for longer distances.