Changes

== Increased sleep needs ==

== Increased sleep needs ==

Sleep needs can be increased temporarily, usually as an effect of needed physical recovery. Such cases include increased [[Exercise|physical activity]]<ref>Erik Naylor, MS, Plamen D. Penev, MD, PhD, Larry Orbeta, BA, Imke Janssen, PhD, Rosemary Ortiz, Egidio F. Colecchia, MS, Moses Keng, MS, Sanford Finkel, MD, Phyllis C. Zee, MD, PhD (January 2000). ''[https://academic.oup.com/sleep/article/23/1/1/2749954 Daily Social and Physical Activity Increases Slow-Wave Sleep and Daytime Neuropsychological Performance in the Elderly.]'' Sleep, Volume 23, Issue 1, January 2000, Pages 1–9, <nowiki>https://doi.org/10.1093/sleep/23.1.1f</nowiki></ref><ref>Markus Dworak, Alfred Wiater, Dirk Alfer, Egon Stephan, Wildor Hollmann, Heiko K. Strüder (March 2008). ''[https://www.sciencedirect.com/science/article/abs/pii/S1389945707001815 Increased slow wave sleep and reduced stage 2 sleep in children depending on exercise intensity]''. Sleep Medicine, Volume 9, Issue 3, March 2008, Pages 266-272, https://doi.org/10.1016/j.sleep.2007.04.017</ref>, some substances, such as [[cannabis]]<ref>Barratt, E. S., Beaver, W., & White, R. (1974). ''[https://psycnet.apa.org/record/1974-24717-001 The effects of marijuana on human sleep patterns]''. Biological Psychiatry, 8(1), 47–54.</ref> or [[alcohol]]<ref>Irshaad O. Ebrahim, Colin M. Shapiro, Adrian J. Williams, Peter B. Fenwick (January 2013). ''[https://onlinelibrary.wiley.com/doi/abs/10.1111/acer.12006 Alcohol and Sleep I: Effects on Normal Sleep]''. Alcoholism: Clinical & Experimental Research, Volume 37, Issue 4, April 2013, Pages 539-708, https://doi.org/10.1111/acer.12006</ref>. External impact sometimes can significantly increase sleep needed, mostly [[wikipedia:Slow-wave_sleep|SWS]], which can shake the adapted state, again depending on the total sleep time of the schedule. This is the main reason why schedules with at least 3 sleep cycles are commonly recommended<ref>[https://www.polyphasic.net polyphasic.net]. Retrieved 07-12-2020.</ref> in the polyphasic community for those with intense physical activity, to guarantee the possibility to accomodate enough SWS in core(-s).  

Sleep needs can be increased temporarily, usually as an effect of needed physical recovery. Such cases include increased [[Exercise|physical activity]]<ref>Erik Naylor, MS, Plamen D. Penev, MD, PhD, Larry Orbeta, BA, Imke Janssen, PhD, Rosemary Ortiz, Egidio F. Colecchia, MS, Moses Keng, MS, Sanford Finkel, MD, Phyllis C. Zee, MD, PhD (January 2000). ''[https://academic.oup.com/sleep/article/23/1/1/2749954 Daily Social and Physical Activity Increases Slow-Wave Sleep and Daytime Neuropsychological Performance in the Elderly.]'' Sleep, Volume 23, Issue 1, January 2000, Pages 1–9, <nowiki>https://doi.org/10.1093/sleep/23.1.1f</nowiki></ref><ref>Markus Dworak, Alfred Wiater, Dirk Alfer, Egon Stephan, Wildor Hollmann, Heiko K. Strüder (March 2008). ''[https://www.sciencedirect.com/science/article/abs/pii/S1389945707001815 Increased slow wave sleep and reduced stage 2 sleep in children depending on exercise intensity]''. Sleep Medicine, Volume 9, Issue 3, March 2008, Pages 266-272, https://doi.org/10.1016/j.sleep.2007.04.017</ref>, some substances, such as [[cannabis]]<ref>Barratt, E. S., Beaver, W., & White, R. (1974). ''[https://psycnet.apa.org/record/1974-24717-001 The effects of marijuana on human sleep patterns]''. Biological Psychiatry, 8(1), 47–54.</ref> or [[alcohol]]<ref>Irshaad O. Ebrahim, Colin M. Shapiro, Adrian J. Williams, Peter B. Fenwick (January 2013). ''[https://onlinelibrary.wiley.com/doi/abs/10.1111/acer.12006 Alcohol and Sleep I: Effects on Normal Sleep]''. Alcoholism: Clinical & Experimental Research, Volume 37, Issue 4, April 2013, Pages 539-708, https://doi.org/10.1111/acer.12006</ref>. External impact sometimes can significantly increase sleep needed, mostly [[wikipedia:Slow-wave_sleep|SWS]], which can shake the adapted state, again depending on the total sleep time of the schedule. This is the main reason why schedules with at least 3 sleep cycles are commonly recommended<ref>[https://www.polyphasic.net polyphasic.net]. Retrieved 07-12-2020.</ref> in the polyphasic community for those with intense physical activity, to guarantee the possibility to acomodate enough SWS in core(-s).  

In some cases, [[wikipedia:Rapid_eye_movement_sleep|REM]] sleep can be increased as well, this includes depression<ref>Mathias Berger, Dieter Riemann (December 1993). ''[https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2869.1993.tb00092.x REM sleep in depression—an overview]''. Journal of Sleep Research, Volume 2, Issue 4, December 1993, Pages 211-223, https://doi.org/10.1111/j.1365-2869.1993.tb00092.x</ref> or possibly intense mental activity<ref>J. De Koninck, D. Lorrain, G. Christ, G. Proulx, D.Coulombe (September 1989). ''[https://www.sciencedirect.com/science/article/abs/pii/0167876089900184 Intensive language learning and increases in rapid eye movement sleep: evidence of a performance factor]''. International Journal of Psychophysiology, Volume 8, Issue 1, September 1989, Pages 43-47, https://doi.org/10.1016/0167-8760(89)90018-4</ref>.

In some cases, [[wikipedia:Rapid_eye_movement_sleep|REM]] sleep can be increased as well, this includes depression<ref>Mathias Berger, Dieter Riemann (December 1993). ''[https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2869.1993.tb00092.x REM sleep in depression—an overview]''. Journal of Sleep Research, Volume 2, Issue 4, December 1993, Pages 211-223, https://doi.org/10.1111/j.1365-2869.1993.tb00092.x</ref> or possibly intense mental activity<ref>J. De Koninck, D. Lorrain, G. Christ, G. Proulx, D.Coulombe (September 1989). ''[https://www.sciencedirect.com/science/article/abs/pii/0167876089900184 Intensive language learning and increases in rapid eye movement sleep: evidence of a performance factor]''. International Journal of Psychophysiology, Volume 8, Issue 1, September 1989, Pages 43-47, https://doi.org/10.1016/0167-8760(89)90018-4</ref>. The latter is still controversial though, because some other studies<ref>J. M. Siegel (November 2001). ''[https://pubmed.ncbi.nlm.nih.gov/11691984/ The REM sleep-memory consolidation hypothesis]''. doi:10.1126/science.1063049</ref> showed no connection between REM duration and studying intensity.

== Flexing ==

== Flexing ==