Jet lag
Discovery and History: – Aviator Wiley Post’s 1931 book, ‘Around the World in Eight Days,’ first documented the effects of flying across time zones. – […]
Discovery and History:
– Aviator Wiley Post’s 1931 book, ‘Around the World in Eight Days,’ first documented the effects of flying across time zones.
– The Federal Aviation Administration’s 1969 study further highlighted the impact of jet lag.
– Post’s observations laid the foundation for understanding circadian rhythms.
– His early work remains relevant in the study of jet lag today.
Symptoms and Effects:
– Jet lag symptoms include sleep disturbances, cognitive effects, dizziness, nausea, and fatigue.
– The Liverpool Jet Lag Questionnaire helps assess these symptoms.
– Athletes traveling across time zones may experience significant performance impacts.
– Digestion, appetite, and overall well-being can be affected by jet lag.
Causes and Mechanisms:
– Jet lag disrupts the body’s natural patterns, affecting sleep and hormone regulation.
– The body clock becomes out of sync with the destination’s day-night cycle.
– Adaptation to new rhythms varies among individuals.
– The International Date Line is not a direct contributor to jet lag; it is primarily linked to distance traveled along the east-west axis.
Travel Fatigue and Circadian Rhythms:
– Travel fatigue can be caused by disruptions in routine, cramped spaces, and low oxygen levels.
– Dehydration and limited food worsen travel fatigue.
– Unlike jet lag, travel fatigue often resolves after a day of rest.
– Circadian rhythms play a role in jet lag and travel fatigue.
Pharmacotherapy and Mental Health Implications:
– Short-term use of hypnotic medication can reduce jet lag-related insomnia.
– Medications like zolpidem have been effective in improving sleep quality across time zones.
– Jet lag can impact mental health by disrupting circadian rhythms.
– Crossing many time zones may increase relapse risk for bipolar and psychotic disorders.
Jet lag, or desynchronosis, is a temporary physiological condition that occurs when a person's circadian rhythm is out of sync with the time zone they are in, and is a typical result from travelling rapidly across multiple time zones (east–west or west–east). For example, someone travelling from New York to London, i.e. from west to east, feels as if the time were five hours earlier than local time, and someone travelling from London to New York, i.e. from east to west, feels as if the time were five hours later than local time. The phase shift when travelling from east to west is referred to as phase-delay of the circadian cycle, whereas going west to east is phase-advance of the cycle. Most travellers find that it is harder to adjust time zones when travelling east. Jet lag was previously classified as a circadian rhythm sleep disorder.
| Jet lag | |
|---|---|
| Other names | Desynchronosis, circadian dysrhythmia |
 | |
| World clocks | |
| Specialty | Psychiatry, neurology, aviation medicine |
The condition may last several days before a traveller becomes fully adjusted to a new time zone; it takes on average one day per time zone crossed to reach circadian reentrainment. Jet lag is especially an issue for airline pilots, aircraft crew, and frequent travellers. Airlines have regulations aimed at combating pilot fatigue caused by jet lag.
The term jet lag is used because before the arrival of passenger jet aircraft, it was uncommon to travel far and fast enough to cause the condition.