On November 1, 2026, most Americans will turn their clocks back one hour and return to standard time.
There is a real possibility that the familiar twice-a-year ritual may not continue forever.
In July, the U.S. House of Representatives passed the Sunshine Protection Act by a vote of 308 to 117. The legislation would make daylight saving time permanent for most of the country, eliminating the spring and fall clock changes. The Senate has not yet passed the bill, so seasonal time changes remain the law for now. [1]
For anyone tired of resetting clocks, changing kids' schedules, adjusting workout routines, and feeling slightly off twice a year, ending the time change has obvious appeal.
The harder question is what time we should keep.
The sleep and circadian science communities have taken a surprisingly strong position on that issue. The American Academy of Sleep Medicine supports eliminating seasonal clock changes, but it recommends permanent standard time rather than permanent daylight saving time. [2]
The reason comes down to light.
Our internal clocks are tied to the sun much more closely than they are tied to the numbers on a clock. Standard time keeps those two systems more closely aligned, particularly by preserving more morning light during the darkest months of the year.
That difference can matter for sleep, alertness, mood, morning exercise, school schedules, and the way our bodies regulate a 24-hour day.
First, What Is the Difference Between Standard Time and Daylight Saving Time?
Standard time is the clock schedule that more closely follows solar time.
Daylight saving time moves the clock one hour ahead during the warmer months. Sunrise and sunset therefore occur an hour later according to the clock.
That shift gives us more evening daylight.
If sunset would occur at 7 p.m. on standard time, daylight saving time makes it 8 p.m. instead. The tradeoff happens in the morning, when sunrise also moves an hour later.
For much of spring and summer, that feels like a reasonable exchange. The sun rises very early anyway, and an extra hour of light after work can be enjoyable.
Winter changes the calculation.
Days are already short. Moving sunrise an hour later can push morning light well beyond the time when many adults and children are waking, commuting, exercising, or starting school.
In northern parts of the United States, permanent daylight saving time could mean winter sunrises after 9 a.m. in some locations. The American Academy of Sleep Medicine has specifically warned that northern states would experience particularly dark winter mornings under permanent daylight saving time. [3]
That is where circadian biology enters the debate.
Why Morning Light Matters So Much
Your circadian rhythm is the roughly 24-hour internal timing system that helps regulate sleep, alertness, body temperature, hormones, appetite, and many other physiological processes.
Light is its most powerful environmental signal.
Specialized cells in the retina detect light and send information to the suprachiasmatic nucleus in the brain, often described as the body's master circadian clock. That system uses the timing of light exposure to help determine when the body should promote wakefulness and when it should prepare for sleep.
Morning light tends to shift the circadian system earlier.
Evening light tends to shift it later.
That distinction is central to the argument for standard time.
The American Academy of Sleep Medicine notes that human sleep-wake patterns depend on bright light in the morning and relative darkness in the evening. When morning light is delayed and evening light is extended, the circadian clock is pushed later. [2]
For someone who naturally wants to stay up late, that may sound harmless.
The problem is that work, school, daycare, flights, workouts, and family schedules usually do not move later with the sun.
You still need to wake up at 6:30.
Your body may simply become less ready to do it.
Permanent Daylight Saving Time Pushes the Body Clock Later
Permanent daylight saving time would increase morning darkness and extend evening light throughout the winter.
Both signals push circadian timing later.
The morning gives the brain less of the early light signal that helps reinforce wakefulness.
The evening provides more light at the time when the body should gradually be moving toward melatonin production and sleep.
For people who already struggle with early mornings, the effect can compound.
They wake in darkness.
They commute in darkness.
They may exercise in darkness.
Then they receive more light later in the day, which encourages the internal clock to remain shifted later.
The next morning arrives at the same clock time, but the body is still being asked to wake earlier than its biological timing would prefer.
This mismatch between social time and biological time is sometimes described as social jet lag.
It is not identical to flying across time zones, but the idea is similar. The clock on the wall and the clock inside the body are asking for different schedules.
Why Standard Time Better Matches Human Biology
Standard time preserves earlier morning light and earlier evening darkness.
That makes it more closely aligned with the natural solar day.
In its updated position statement, the American Academy of Sleep Medicine concluded that permanent standard time is the option that best aligns with human circadian biology and provides the strongest health and safety benefits. [2]
The National Sleep Foundation, Sleep Research Society, and Society for Research on Biological Rhythms have also supported permanent standard time.
The argument is not that everyone immediately sleeps perfectly under standard time.
People still stay up too late.
Screens still exist.
Work schedules can still conflict with individual chronotypes.
Winter days are still short.
Standard time simply places the available daylight in a location that better supports the body's natural timing system.
Earlier light helps anchor the morning.
Earlier darkness helps support the evening transition toward sleep.
What This Means for Morning Training
The issue becomes especially tangible for anyone who trains before work.
A morning runner may already leave the house in darkness during December and January.
Under permanent daylight saving time, that dark period would extend even later into the morning.
There are practical consequences to that, including visibility and safety. There is also a behavioral component.
Outdoor exercise tends to feel easier when the environment supports wakefulness. Morning light helps suppress melatonin, increases alertness, and reinforces the circadian signal that daytime has begun.
A dark 6 a.m. run in January will never feel like a sunny June morning, regardless of the clock policy.
Permanent standard time at least moves sunrise an hour closer to the period when people are waking and becoming active.
This matters for consistency.
Exercise habits are easier to maintain when they fit the body's broader daily rhythm. If a schedule repeatedly asks you to train while your circadian system is still promoting sleep, the workout may feel harder to start even if your physical capacity is unchanged.
The Case for Permanent Daylight Saving Time
There is a legitimate argument on the other side.
People like evening light.
An additional hour of daylight after work or school creates more opportunity for walking, running, cycling, sports, playground time, yard work, shopping, and social activity.
That has obvious appeal.
Some research has also linked daylight saving time with increased evening physical activity, and studies have explored possible effects on crime, traffic safety, retail activity, and energy use.
The evidence across those areas is mixed.
Energy savings, one of the original reasons governments adopted daylight saving time, appear much smaller and less consistent than early advocates expected. Modern homes use energy differently than homes did a century ago, and savings from reduced evening lighting can be offset by heating or cooling demand at other times.
Traffic outcomes are also complicated because morning and evening risks move in opposite directions. More evening light may improve visibility after work, while darker mornings can increase risk during school and commuting hours.
That does not make the pro-DST argument unreasonable.
It means the choice involves tradeoffs.
From a sleep and circadian perspective, however, the tradeoff is more one-sided. Morning light has a particularly important biological role in anchoring the circadian clock, which is why sleep organizations overwhelmingly favor standard time.
We Have Tried Permanent Daylight Saving Time Before
The United States has already conducted something close to this experiment.
During the energy crisis of the early 1970s, Congress enacted year-round daylight saving time beginning in January 1974.
The idea was initially popular.
Then winter mornings arrived.
In cities including Minneapolis, Detroit, Indianapolis, and Seattle, sunrise occurred around 9 a.m. People were commuting and children were heading to school in darkness. Safety concerns grew, particularly around children waiting for school buses and crossing roads before sunrise.
Public support collapsed quickly.
Historical polling showed that support for year-round daylight saving time fell sharply within only a few months. Congress ultimately ended the experiment early and restored seasonal clock changes later in 1974. [4]
The history does not prove that Americans would respond exactly the same way today.
Work schedules have changed.
Remote work exists.
School policies could adjust.
Lighting and transportation have improved.
But the sun has not changed.
Permanent daylight saving time would still create very late winter sunrises.
What Congress Is Considering Now
The current debate has become much more active.
The House passed the Sunshine Protection Act in July 2026 by a vote of 308 to 117. The legislation would move most of the country to permanent daylight saving time while allowing certain existing standard-time exemptions to remain. [1]
A competing proposal, the Sunshine for Our Kids Act, was introduced in the House in July. That bill takes essentially the opposite approach. It would establish permanent standard time nationally while allowing individual states to choose daylight saving time if they wanted it. [5]
States are also moving independently.
Under current federal law, states may opt out of daylight saving time and remain on standard time throughout the year, as Hawaii and most of Arizona already do. States cannot independently choose permanent daylight saving time without a change in federal law. [6]
Nineteen states have already enacted legislation that would move them toward permanent daylight saving time if Congress grants that authority. Meanwhile, permanent-standard-time proposals have gained increasing attention as sleep and health groups have become more involved in the debate. [7]
The National Conference of State Legislatures reported that 20 states had introduced 28 time-related bills during 2026 as of October. [8]
There is therefore considerable agreement that changing clocks twice a year is unpopular.
The disagreement is increasingly about which clock to keep.
Why the Clock Change Itself Causes Problems
Even if permanent standard time is biologically preferable, the twice-yearly transition creates problems of its own.
The spring transition is especially disruptive because people lose an hour of clock time overnight.
Research has associated the spring shift with short-term increases in sleep loss, motor vehicle crashes, cardiovascular events, medical errors, and other adverse outcomes.
The fall shift is generally easier because the clock moves backward and people gain an hour.
Even then, the timing change can temporarily disturb sleep schedules, particularly in young children, older adults, shift workers, and people with very consistent routines.
This is why the sleep-medicine position has two separate components.
Ending the clock change is one goal.
Choosing standard time is the other.
Those questions are often bundled together politically, but biologically they are different.
What Happens to Sleep Under Permanent Daylight Saving Time?
Permanent daylight saving time would not suddenly create widespread insomnia.
The effects would be subtler.
People would receive less morning light during winter.
They would receive more light later in the evening.
Average circadian timing would tend to shift later.
People who must still wake early for work or school could end up with a larger gap between their biological preference and their required schedule.
That gap can show up as shorter sleep duration, harder mornings, greater dependence on alarms and caffeine, and larger differences between weekday and weekend sleep.
Teenagers may be especially vulnerable because adolescence naturally shifts circadian timing later.
People living farther north would also experience larger effects because winter mornings are already darker for longer.
The farther sunrise moves beyond the time people need to start their day, the more important artificial schedules become relative to the natural light-dark cycle.
What About Seasonal Affective Disorder?
Morning light is also relevant to mood.
Bright-light therapy delivered in the morning is an established treatment for seasonal affective disorder, and circadian timing is considered one of the mechanisms involved.
Permanent daylight saving time would not cause seasonal depression on its own.
It would, however, reduce natural morning light exposure during the part of the year when many people already receive very little of it.
For someone who wakes before sunrise, drives to work before sunrise, and spends most of the day indoors, moving sunrise an additional hour later can make meaningful outdoor morning light even harder to obtain.
That is another reason northern regions feature heavily in the permanent-time debate.
How to Handle the Fall Clock Change This Year
Whatever Congress ultimately decides, most Americans will still move back to standard time on November 1, 2026.
The fall transition is usually the easier one.
A few habits can make it smoother.
Keep bedtime and wake time reasonably consistent rather than treating the extra hour as permission to stay up dramatically later.
Get outside for morning light after the change. That earlier sunlight is useful for helping the circadian clock align with the new schedule.
Move meals, exercise, and other daily routines with the clock rather than leaving half of your schedule on the old time.
For parents, expect young children to wake according to their old internal clock for several days. Gradually moving bedtime and morning routines in the days before the change can make that adjustment easier.
Most people will adapt fairly quickly.
The larger question is whether we should keep putting everyone through the transition twice a year.
The Sleep Case for Standard Time
There are plenty of reasons to like long summer evenings.
I like them too.
More light after work makes it easier to run, ride, eat outside, play with kids, and stay active.
But choosing a permanent national clock is different from choosing the nicest summer evening.
The harder test is December.
Where should limited winter daylight fall?
From a circadian perspective, the stronger case is in the morning.
Morning light helps set the internal clock, supports alertness, and reinforces an earlier sleep-wake schedule.
Evening light tends to delay that clock.
That basic biology is why the major sleep and circadian organizations have arrived at the same recommendation.
Stop changing the clocks.
Keep standard time.
For anyone thinking about sleep as part of performance, whether that means training, working, parenting, or simply trying to feel better in the morning, the principle is useful even if Congress never changes the law.
Give your body light early.
Keep the schedule consistent.
Respect the fact that your internal clock responds to the sun, not just the numbers on your phone.
We can change the clock by an hour overnight.
The body takes longer to follow.
Sources
- U.S. House of Representatives. “Sunshine Protection Act,” H.R. 139. House Roll Call Vote 238, July 14, 2026. The bill passed 308-117.
- Rishi MA, Cheng JY, Strang AR, et al. “Permanent Standard Time Is the Optimal Choice for Health and Safety: An American Academy of Sleep Medicine Position Statement.” Journal of Clinical Sleep Medicine. 2024;20(1):121-125. https://pubmed.ncbi.nlm.nih.gov/37904574/
- American Academy of Sleep Medicine. “Sleep Experts Advocate for Permanent Standard Time.” AASM.
- Congressional Research Service and historical reporting on the Emergency Daylight Saving Time Energy Conservation Act of 1973 and the 1974 year-round DST experiment.
- U.S. Congress. “Sunshine for Our Kids Act of 2026,” H.R. 9638. Introduced July 9, 2026.
- U.S. Department of Transportation. “Uniform Time.” Federal guidance on the Uniform Time Act and state authority regarding daylight saving time.
- Congressional Research Service. “Daylight Saving Time.” Updated July 24, 2026.
- National Conference of State Legislatures. “Daylight Saving Time: State Legislation.” Updated October 12, 2026.
