From Natural Rhythms to Circadian Physiology

This lecture is intended for you to understand what is circadian physiology, and the concept of natural rhythms. This lecture helps you understand how our bodies are connected to internal…

Please upgrade for access. You must enroll in the Systems Health® Educator Masters Certification Program.

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience.

Necessary

Always Enabled

Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.

Cookie	Duration	Description
cookielawinfo-checkbox-advertisement	1 year	Set by the GDPR Cookie Consent plugin, this cookie records the user consent for the cookies in the "Advertisement" category.
cookielawinfo-checkbox-analytics	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-analytics	1 year	Set by the GDPR Cookie Consent plugin, this cookie records the user consent for the cookies in the "Analytics" category.
cookielawinfo-checkbox-functional	11 months	The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-functional	1 year	The GDPR Cookie Consent plugin sets the cookie to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-necessary	1 year	Set by the GDPR Cookie Consent plugin, this cookie records the user consent for the cookies in the "Necessary" category.
cookielawinfo-checkbox-others	1 year	Set by the GDPR Cookie Consent plugin, this cookie stores user consent for cookies in the category "Others".
cookielawinfo-checkbox-others	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance	1 year	Set by the GDPR Cookie Consent plugin, this cookie stores the user consent for cookies in the category "Performance".
cookielawinfo-checkbox-performance	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
CookieLawInfoConsent	1 year	CookieYes sets this cookie to record the default button state of the corresponding category and the status of CCPA. It works only in coordination with the primary cookie.
cross-site-cookie	session	Shopoe sets this cookie to ensures visitor browsing security by preventing cross-site request forgery. This cookie is essential for the security of the website and visitors.
m	1 year 1 month 4 days	Stripe sets this cookie for fraud prevention purposes. It identifies the device used to access the website, allowing the website to be formatted accordingly.
PHPSESSID	session	This cookie is native to PHP applications. The cookie stores and identifies a user's unique session ID to manage user sessions on the website. The cookie is a session cookie and will be deleted when all the browser windows are closed.
server_session_id	session	This cookie is set by Twitch to help in load balancing and optimizing the visitor experience.
unique_id	1 year 1 month	Twitch TV sets this cookie for its online service used for watching or broadcasting live or prerecorded videos across topics such as cooking, travel, art, sports, and video games.
viewed_cookie_policy	11 months	The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
viewed_cookie_policy	1 year	The GDPR Cookie Consent plugin sets the cookie to store whether or not the user has consented to use cookies. It does not store any personal data.
wp_woocommerce_session_*	2 days	WooCommerce sets this cookie to make a unique code for each customer so that it knows where to find the cart data in the database for each one.
XSRF-TOKEN	2 hours	This cookie enhances visitor browsing security by preventing cross-site request forgery.
_wpfuuid	1 year 1 month 4 days	This cookie is used by the WPForms WordPress plugin. The cookie is used to allows the paid version of the plugin to connect entries by the same user and is used for some additional features like the Form Abandonment addon.
__cf_bm	1 hour	This cookie, set by Cloudflare, is used to support Cloudflare Bot Management.
__stripe_mid	1 year	Stripe sets this cookie to process payments.
__stripe_sid	1 hour	Stripe sets this cookie to process payments.

Functional

Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.

Cookie	Duration	Description
api_token	1 year 1 month	This cookie is set by Twitch to display the embedded video and the services required to function the same.
currency	session	This cookie is used to store the currency preference of the user.
yt-player-bandwidth	never	The yt-player-bandwidth cookie is used to store the user's video player preferences and settings, particularly related to bandwidth and streaming quality on YouTube.
yt-player-headers-readable	never	The yt-player-headers-readable cookie is used by YouTube to store user preferences related to video playback and interface, enhancing the user's viewing experience.
yt-remote-cast-available	session	The yt-remote-cast-available cookie is used to store the user's preferences regarding whether casting is available on their YouTube video player.
yt-remote-cast-installed	session	The yt-remote-cast-installed cookie is used to store the user's video player preferences using embedded YouTube video.
yt-remote-connected-devices	never	YouTube sets this cookie to store the user's video preferences using embedded YouTube videos.
yt-remote-device-id	never	YouTube sets this cookie to store the user's video preferences using embedded YouTube videos.
yt-remote-fast-check-period	session	The yt-remote-fast-check-period cookie is used by YouTube to store the user's video player preferences for embedded YouTube videos.
yt-remote-session-app	session	The yt-remote-session-app cookie is used by YouTube to store user preferences and information about the interface of the embedded YouTube video player.
yt-remote-session-name	session	The yt-remote-session-name cookie is used by YouTube to store the user's video player preferences using embedded YouTube video.
ytidb::LAST_RESULT_ENTRY_KEY	never	The cookie ytidb::LAST_RESULT_ENTRY_KEY is used by YouTube to store the last search result entry that was clicked by the user. This information is used to improve the user experience by providing more relevant search results in the future.

Performance

Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.

Cookie	Duration	Description
unique_id_durable	1 year 1 month	Cookie that is used to register whether the user is logged in. This allows the website owner to make parts of the website inaccessible, based on the user's log-in status.
_uetsid	never	Bing Ads sets this cookie to engage with a user that has previously visited the website.
_uetvid	never	Bing Ads sets this cookie to engage with a user that has previously visited the website.

Analytics

Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.

Cookie	Duration	Description
referrer_url	1 hour	This cookie is used to detect how the user reached the website by registering their last URL-address.
sbjs_current	session	Sourcebuster sets this cookie to identify the source of a visit and stores user action information in cookies. This analytical and behavioural cookie is used to enhance the visitor experience on the website.
sbjs_current_add	session	Sourcebuster sets this cookie to identify the source of a visit and stores user action information in cookies. This analytical and behavioural cookie is used to enhance the visitor experience on the website.
sbjs_first	session	Sourcebuster sets this cookie to identify the source of a visit and stores user action information in cookies. This analytical and behavioural cookie is used to enhance the visitor experience on the website.
sbjs_first_add	session	Sourcebuster sets this cookie to identify the source of a visit and stores user action information in cookies. This analytical and behavioural cookie is used to enhance the visitor experience on the website.
sbjs_migrations	session	Sourcebuster sets this cookie to identify the source of a visit and stores user action information in cookies. This analytical and behavioural cookie is used to enhance the visitor experience on the website.
sbjs_session	1 hour	Sourcebuster sets this cookie to identify the source of a visit and stores user action information in cookies. This analytical and behavioural cookie is used to enhance the visitor experience on the website.
sbjs_udata	session	Sourcebuster sets this cookie to identify the source of a visit and stores user action information in cookies. This analytical and behavioural cookie is used to enhance the visitor experience on the website.
tk_ai	1 year 1 month 4 days	JetPack sets this cookie to store a randomly-generated anonymous ID used only within the admin area and for general analytics tracking.
tk_lr	1 year	JetPack plugin sets this referral cookie on sites using WooCommerce, which analyzes referrer behaviour for Jetpack.
tk_or	1 year 1 month 4 days	JetPack plugin sets this referral cookie on sites using WooCommerce, which analyzes referrer behaviour for Jetpack.
tk_qs	1 hour	JetPack sets this cookie to store a randomly-generated anonymous ID used only within the admin area and for general analytics tracking.
tk_r3d	3 days	JetPack installs this cookie to collect internal metrics for user activity and improve user experience.
tk_tc	session	JetPack sets this cookie to record details on how users use the website.
_ga	1 year 1 month 4 days	Google Analytics sets this cookie to calculate visitor, session and campaign data and track site usage for the site's analytics report. The cookie stores information anonymously and assigns a randomly generated number to recognise unique visitors.
_gat_gtag_UA_*	1 minute	Google Analytics sets this cookie to store a unique user ID.
_ga_*	1 year 1 month 4 days	Google Analytics sets this cookie to store and count page views.
_gid	1 day	Google Analytics sets this cookie to store information on how visitors use a website while also creating an analytics report of the website's performance. Some of the collected data includes the number of visitors, their source, and the pages they visit anonymously.

Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.

Cookie	Duration	Description
experiment_overrides	1 year 1 month	Twitch TV sets this cookie to collect data on the user across websites. This information is used to tailor advertisements.
guest_id	1 year 1 month 1 minute	Twitter sets this cookie to identify and track the website visitor. It registers if a user is signed in to the Twitter platform and collects information about ad preferences.
IDE	1 year 24 days	Google DoubleClick IDE cookies store information about how the user uses the website to present them with relevant ads according to the user profile.
muc_ads	1 year 1 month 4 days	Twitter sets this cookie to collect user behaviour and interaction data to optimize the website.
MUID	1 year 24 days	Bing sets this cookie to recognise unique web browsers visiting Microsoft sites. This cookie is used for advertising, site analytics, and other operations.
NID	6 months	Google sets the cookie for advertising purposes; to limit the number of times the user sees an ad, to unwanted mute ads, and to measure the effectiveness of ads.
personalization_id	1 year 1 month 4 days	Twitter sets this cookie to integrate and share features for social media and also store information about how the user uses the website, for tracking and targeting.
PREF	8 months	PREF cookie is set by Youtube to store user preferences like language, format of search results and other customizations for YouTube Videos embedded in different sites.
test_cookie	past	doubleclick.net sets this cookie to determine if the user's browser supports cookies.
ttwid	1 year	Tiktok sets this cookie to keep track of user authentication and session information.
VISITOR_INFO1_LIVE	6 months	YouTube sets this cookie to measure bandwidth, determining whether the user gets the new or old player interface.
VISITOR_PRIVACY_METADATA	6 months	YouTube sets this cookie to store the user's cookie consent state for the current domain.
YSC	session	Youtube sets this cookie to track the views of embedded videos on Youtube pages.
yt.innertube::nextId	never	YouTube sets this cookie to register a unique ID to store data on what videos from YouTube the user has seen.
yt.innertube::requests	never	YouTube sets this cookie to register a unique ID to store data on what videos from YouTube the user has seen.

Others

Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.

Cookie	Duration	Description
0af9fc9e4dca6c9a53d304e1c6b5306e	1 hour	Description is currently not available.
cometly_tracker_session	2 hours	Description is currently not available.
csrfToken	1 month 1 day	Description is currently not available.
egh2ePgYbsmDS5GUqmvPVvi5A4rfOC5EPhiN8wzA	2 hours	Description is currently not available.
ga__15_abel	1 day	Description is currently not available.
ga__15_abel-ssn	1 day	Description is currently not available.
hmt_id	1 month	Description is currently not available.
jwt	1 month 1 day	No description available.
jwtOnAir	1 month 1 day	Description is currently not available.
key	1 hour	Description is currently not available.
KP_UIDz	1 day	No description available.
KP_UIDz-ssn	1 day	Description is currently not available.
KP_UIDZ_1	1 day	Description is currently not available.
KP_UIDZ_1-ssn	1 day	Description is currently not available.
msToken	10 days 1 minute	Description is currently not available.
qNRJiqVciHAavbJpb2Q9fr1SE4a5d0yqWVrKA7Wu	2 hours	Description is currently not available.
viewer_id	1 year	No description available.
volume	never	No description available.
yptDeviceID	1 year	Description is currently not available.
_cfuvid	session	Description is currently not available.
__cflb	1 hour	This cookie is used by Cloudflare for load balancing.