Reychler G, et al. - Because the 1-minute sit-to-stand test (STST) is simple to perform and has been validated in adults, but not yet in children, investigators assessed the concurrent validity and reliability of the STST in measuring the heart rate (HR) response to submaximal exercise and functional exercise capacity in children. In children, the physiological response related to this test is unknown. Recognition in children with cardiac or respiratory diseases is important for physical activity, and HR response measurement during exercise is needed. New field tests are emerging to counteract the 6-minute walking test (6MWT)-related practical drawbacks. The 6MWT, verified for children's validity and reliability, is the reference field test for functional exercise capacity measurement.