The Physiology Understanding (PhUn) Week is a national outreach event sponsored by the American Physiological Society. Our PhUn team conducted an event for 551 students (12.5 ± 0.9 yr old) in a middle school in Indiana. The aims of this program were to: (1) teach about the negative consequences of inactivity on cardiovascular (CV) health and overall well-being; (2) help students to determine their own CV fitness level and design their fitness plan; and (3) test the hypothesis that students who are offered daily physical education (PE) classes are able to meet the Physical Activity Guidelines for Americans. The University of Louisville PhUn team visited the school during school hours to execute the outreach program to students enrolled in Health and PE as their course elective. During the event, students were educated about CV physiology and the effects of exercise on CV fitness and metabolism. Additionally, students were asked to completed a questionnaire about their physical activity behaviors outside the school. Students were also educated about ways to increase energy expenditure by 150 METy (units of metabolism for youth) per day during 7 days. CV fitness levels were estimated by using the PACER (Progressive Aerobic Cardiovascular Endurance Run) test, and students were asked to create a plan to increase energy expenditure daily. The results showed that 53% of the students did not perform enough physical activity outside school to meet the guidelines. In conclusion, the incorporation of PE in schools is critical to cultivate healthy lifestyles and decrease the sedentarism epidemic in the U.S.