Slow breathing can alter cardiorespiratory and autonomic measures and can change subjective state in healthy people.

This page isolates one claim from the wider argument of The Human OS Manual.

The classification describes the evidence supporting this claim, not the Human OS framework as a whole.

A systematic review and physiological review describe changes in heart-rate variability, respiratory-cardiac coupling, baroreflex/chemoreflex measures, and subjective outcomes during slow breathing.

The evidence does not establish one universally optimal breathing rate, guarantee calm, or show that slow breathing resolves the causes of chronic stress. The systematic-review literature is heterogeneous and relatively small.

The book uses slow breathing as an accessible state lever. The public claim stays with measured psychophysiological effects rather than the broader Human OS interpretation of a widened response window.

Developing findings or mechanisms that help explain possibility without establishing universal outcomes or direct real-world effects.

Sources are listed according to the role they play in this claim. One source may provide direct support, another may explain a mechanism, establish a limitation, or prevent an interpretation from becoming broader than the evidence allows.

The printed book preserves the claim inside the argument that gives it meaning. These references connect the current digital record to the first-edition evidence trail.

This claim connects to the following parts of the Human OS architecture. The module labels locate the claim inside the framework; they do not imply that the research source validates the architecture itself.