How well can a brief step test assess exercise tolerance?

A 3-minute step test (3MST) is a valid and reliable way to assess the cardiorespiratory and functional capacity of healthy children, according to a comparison of 3MST with the 6-minute walking test (6MWT), a tool often used for this purpose.

Investigators in Brazil recruited 66 public school children aged from 7 to 11 years old for the comparative study. Participants performed the 3MST with a 20 cm-high wooden step, a nonslip surface, and no handrail. They were instructed to go up and down 24 times a minute, keeping pace with a metronome. The 6MWT was performed in a 30m long flat hallway, with the children instructed to walk as far as possible without running.

Comparisons between the 2 tests with regard to performance variables found that the 3MST was a safe and reproducible way to determine exercise tolerance in healthy children in this age group. Further, compared with the 6MWT, the 3MST is short, easy to perform, and requires less physical space (Teixeira JB, et al. Acta Paediatrica. 2020 ;109[11]:2354-2355).

Thoughts from Dr. Farber

This test is easy enough to perform, requiring just a metronome and a step. I wish the authors had indicated what an abnormal result might be, so you may want to create your own norms. However, everyone they tested (including those who were obese) was able to complete the task so, at the least, a child who cannot complete the test warrants further evaluation before being cleared for participation in sports.