Adopting a polyphasic sleep schedule (such as the Uberman cycle) is detrimental to mental and physical health, as well as cognitive performance.

noli's read

Matthew Walker, a recognized sleep expert, draws here on a robust scientific consensus regarding the structure of human sleep. Research, particularly laboratory studies on sleep deprivation and circadian rhythms (meta-analyses and systematic reviews published in journals such as Nature and Sleep Medicine Reviews), confirms that humans are biologically programmed for monophasic or short biphasic sleep. Extreme polyphasic sleep fragments the cycles necessary for deep sleep and REM sleep, which are essential for recovery. Observational evidence demonstrates that these practices lead to chronic sleep debt, impairing executive functions and mood. While the idea of maximizing waking time is appealing, no rigorous data supports the notion that the human body can healthily adapt to these cycles over the long term. This warning reflects the current state of science, which favors sleep continuity.

the sources

No named source held this one up — that absence is part of the verdict.