The <a class="glossaryLink" style="box-sizing: border-box; background-color: #ffffff; color: #447dd8 !important; text-decoration: none !important; font-size: 16px; border-bottom: 1px dotted #000000; font-family: Montserrat; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal;" href="https://scofa.com/glossary/circadian-rhythm/" aria-describedby="tt" data-cmtooltip="<div class=glossaryItemTitle>Circadian Rhythm</div><div class=glossaryItemBody>The body&#039;s internal clock&#039;s circadian rhythm is a cyclical rhythm set to approximately 24 hours. Genes control it; therefore, it is intrinsic. However, it can also be affected by external stimuli. Light, temperature, exercise, and nutrition are the primary external stimuli.</div>" data-mobile-support="0" data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">circadian rhythm</a> is automatically adjusted to 24 hours, but it needs external stimuli to be compatible with the natural world for the <a class="glossaryLink" style="box-sizing: border-box; background-color: #ffffff; color: #447dd8 !important; text-decoration: none !important; font-size: 16px; border-bottom: 1px dotted #000000; font-family: Montserrat; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal;" href="https://scofa.com/glossary/light-dark-cycle/" aria-describedby="tt" data-cmtooltip="<div class=glossaryItemTitle>Light-Dark Cycle</div><div class=glossaryItemBody>The light-dark cycle refers to the light and dark times of the day. Light is the primary stimulus synchronizing humans&#039; biological clock with the world&#039;s light-dark cycle. It&#039;s an important environmental cue that plays a role in human health and well-being.</div>" data-mobile-support="0" data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">light-dark cycle</a>. The foremost of these external stimuli is light. The internal clock must be <a class="glossaryLink" style="box-sizing: border-box; background-color: #ffffff; color: #447dd8 !important; text-decoration: none !important; font-size: 16px; border-bottom: 1px dotted #000000; font-family: Montserrat; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal;" href="https://scofa.com/glossary/synchronized/" aria-describedby="tt" data-cmtooltip="<div class=glossaryItemTitle>Synchronized</div><div class=glossaryItemBody>Synchronized sleep is another name for non-REM sleep. It consists of 4 successive phases, in each phase the sleep becomes deeper and deeper. Stage 5 is REM sleep, also called desynchronized sleep.</div>" data-mobile-support="0" data-gt-translate-attributes="[{"attribute":"data-cmtooltip", "format":"html"}]">synchronized</a> with the external clock through these stimuli, a process called entrainment. Entrainment is our spontaneous circadian rhythm synchronizing the sleep-wake phases with the external clock.
