Comment on Eckberg <i>et al</i>. 2016

The subsequent two sentences are incorrect: “Although healthy subjects breathe spontaneously over a wide range of frequencies … 0.11 Hz is far below the average breathing frequencies of healthy subjects. Moreover, fully 70% of Cooper's subjects breathed at rates below ∼0.22–0.28 Hz ”. It is not abnormal to breath spontaneously at just below 13–17 breaths per minute (0.22–0.28 Hz) nor at 7 breaths per minute (0.1 Hz). The views expressed are those of the authors and not necessarily those of the National Health Service, the National Institute for Health Research or the Department of Health.