This document summarizes a study that estimated VO2max (maximal oxygen consumption) levels in participants using various exercise tests. It found that estimates of VO2max can vary depending on the test used, and are also affected by individual factors like genetics, body composition, and training status. The study measured heart rate responses and oxygen consumption during tests like treadmill running, step tests, and 12-minute runs to estimate VO2max in participants and compare the results across tests. It concluded that more accurate VO2max measurements can be obtained in a laboratory setting using expired gas analysis compared to field tests.