Published : 27 Aug 2026, 05:34 AM
Updated : 08 Sep 2026, 09:36 AM
People may be able to train their bodies to wake without an alarm by maintaining a consistent sleep routine and following basic sleep-hygiene habits, according to the BBC.
Adults generally need seven to nine hours of sleep, although individual needs vary.
To test whether the body's circadian rhythm could be reprogrammed, journalist Ally Hirschlag undertook a seven-day experiment without alarms, guided by recommendations from sleep researchers.
Establishing a Baseline Schedule
Before starting, experts advised identifying a natural sleep pattern.
Through observation, Hirschlag established an ideal window of eight and a half hours, sleeping from 11:30pm to 8am.
Helen Burgess, co-director of the sleep and circadian research lab at the University of Michigan, emphasised that maintaining a regular bedtime allows the body to naturally relax into a routine.
Environmental and Lifestyle Adjustments
To sync the internal clock, researchers highlighted several key factors:
• Light exposure: Anna Joyce, a sleep specialist at Regent's University London, noted that daylight turns off melatonin production. Using blackout blinds at night and opening them immediately upon waking triggers cortisol to signal the start of the day. The evening light was dimmed two hours before sleep.
• Temperature control: As core body temperature drops during sleep, room temperatures were lowered at 11pm.
• Screen reduction: To counter the effects of blue light and dopamine-driven engagement, smartphone apps were blocked from 9pm to 12pm, and screens were set to greyscale.
• Dietary limits: Caffeine was restricted to one morning cup, meals were finished three hours before bed, and alcohol was avoided due to its suppression of REM sleep.
Results of the Experiment
Despite minor disruptions -- including an early doorbell, pet interference, and a late night out – Hirschlag woke naturally near her 8am target on most days.
By day four, morning grogginess had reduced significantly.
Eti Ben Simon, associate director of the Sleep Innovation Labs at the University of Texas at Dallas, noted the broader health implications of sleep hygiene, highlighting that sleep disruptions heavily correlate with mental health challenges, particularly in adolescents who frequently miss recommended rest targets.
The experiment demonstrated that while shifting circadian rhythms requires gradual adjustments, consistent sleep hygiene habits can successfully ease reliance on external alarms.
