\n<\/p>\n
March 5, 2026<\/p>\n
3 min read<\/p>\n
Add Us On Google<\/span>Add SciAm<\/span><\/span><\/p>\n How to \u2018spring forward\u2019 for daylight saving time without leaving your body and brain behind<\/p>\n As clocks spring forward, light and movement are cues for daytime wakefulness that can improve sleep and overall health<\/p>\n By Matt Fuchs edited by Tanya Lewis<\/span><\/p>\n Oleg Breslavtsev\/Getty Images<\/p>\n On Sunday at 2 A.M. local time, daylight saving time will begin in most U.S. states, and clocks there will spring forward by an hour. Research shows hospital admissions increase right after this annual clock change, and many people lose sleep for one week or longer. The time change can also exacerbate sleep disorders and depression.<\/p>\n But researchers have identified two behaviors that, when combined in the morning, may stabilize circadian rhythms and ease the transition.<\/p>\n Daylight, absorbed through the eyes in the early morning, activates a pair of pea-sized clusters of cells deep in the brain called the suprachiasmatic nucleus, or SCN. The SCN\u2019s tiny dimensions belie its importance as the body\u2019s primary alarm clock. It sends rhythmic signals to millions of other timekeepers\u2014called peripheral clocks\u2014located in almost every cell with a nucleus in the body. These cells, in turn, switch on genes that prepare our organs for the day\u2019s action, such as consuming and digesting food.<\/p>\n If you’re enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.<\/p>\n The light-triggered SCN has been called the body\u2019s \u201cmaster\u201d clock. But recent research shows that light is just one of several factors that determine our internal sense of time; another is exercise. Karyn Esser, a physiologist at the University of Florida, and her colleagues have found that exercise in the early hours is a powerful cue for the body\u2019s peripheral clocks in oxygen-sensing organs such as the muscles. And other researchers have made similar findings in studies related to the lungs and kidneys. \u201cHealthy circadian rhythms require coordination of clock systems across the body,\u201d Esser says.<\/p>\n Because light and exercise influence circadian rhythms separately through the SCN and peripheral clocks, respectively, scientists think that combining these cues\u2014exercise and morning sunshine\u2014may work better to shift internal clocks to the time of both cues than either light or exercise alone.<\/p>\n Shawn Youngstedt, a professor of exercise science at Arizona State University\u2019s Edson College, and his colleagues tested this combination in a small sample of adults. The researchers found that it produced a larger shift in internal clock timing than just exercise or exposure to light (that was bright enough to simulate sunlight). The combination still needs to be tested in larger studies, Youngstedt says, but exercise \u201chas a significant impact\u201d on the body\u2019s ability to adjust to time shifts.<\/p>\n And scientists know that forceful triggers at dawn help ensure a smooth dusk. The circadian clocks, once set in motion, start a precise countdown to that evening\u2019s release of melatonin\u2014the hormone that lulls us into a relaxed, ready-for-sleep state.<\/p>\n Exercise and daylight exposure may be synergistic in other ways: exercise causes the pupils of our eyes to dilate and capture more light, which could be especially helpful as eyes lose light sensitivity as people age.<\/p>\n Modern schedules and artificial light often interfere with people\u2019s 24-hour biological cycles. Regular disruption to these cycles, or circadian rhythms, is linked to chronic diseases and premature death.<\/p>\n The loss of a single hour when clocks spring forward on March 8 may sound trivial, but the sudden mismatch between our internal clocks and external ones can compromise sleep, well-being, traffic safety and heart health.<\/p>\n To manage these risks, experts suggest you prepare for the transition a few days ahead by using the light-and-locomotion strategy. Wake up 15 to 20 minutes earlier each day from March 5 to 8 and go for an outdoor walk or jog one hour after waking up (indoor light typically isn\u2019t bright enough to reset internal clocks). These incremental changes will acclimate your body to the clock change gradually.<\/p>\n The more body parts you exercise, the better, Esser explains. She suggests that you try to get a little out of breath by exercising at about 50 to 75 percent of full exertion.<\/p>\n This preparation is especially important for older people or those with chronic illnesses. Around age 40, people\u2019s circadian rhythms start to lose flexibility, resulting in \u201clonger adjustments to the clock change and higher probability of a problem,\u201d Esser says.<\/p>\n Certain habits could negate the benefits of the light-and-locomotion strategy. Late-night food or bright light later in the day can shift rhythms later, just as mornings are brightening earlier, says Gad Asher, a biochemist at the Weizmann Institute of Science in Rehovot, Israel, who studies the body\u2019s internal clocks.<\/p>\n After establishing an earlier, stronger circadian rhythm\u2014and springing forward unscathed\u2014don\u2019t throw out your new light-and-exercise habit, Asher says. Keep your rhythm steady to maintain your health for the long haul. \u201cWhat really matters is your daily habits going forward,\u201d he says.<\/p>\n If you enjoyed this article, I\u2019d like to ask for your support. Scientific American<\/span> has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.<\/p>\n I\u2019ve been a Scientific American<\/span> subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm <\/span>always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.<\/p>\n If you subscribe to Scientific American<\/span>, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.<\/p>\n In return, you get essential news, captivating podcasts, brilliant infographics, can’t-miss newsletters, must-watch videos, challenging games, and the science world’s best writing and reporting. You can even gift someone a subscription.<\/p>\n There has never been a more important time for us to stand up and show why science matters. I hope you\u2019ll support us in that mission.<\/p>\n","protected":false},"excerpt":{"rendered":" March 5, 2026 3 min read Add Us On GoogleAdd SciAm How to \u2018spring forward\u2019 for daylight saving time without leaving your body and brain behind As clocks spring forward, light and movement are cues for daytime wakefulness that can improve sleep and overall health By Matt Fuchs edited by Tanya Lewis Oleg Breslavtsev\/Getty Images<\/p>\n","protected":false},"author":1,"featured_media":45924,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[58],"tags":[17561,1868,13202,2666,3818,10078,286],"class_list":{"0":"post-45923","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-adjust","9":"tag-body","10":"tag-daylight","11":"tag-exercise","12":"tag-saving","13":"tag-sunlight","14":"tag-time"},"_links":{"self":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts\/45923","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=45923"}],"version-history":[{"count":0,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts\/45923\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/media\/45924"}],"wp:attachment":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=45923"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=45923"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=45923"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}On supporting science journalism<\/h2>\n
It\u2019s Time to Stand Up for Science<\/h2>\n