Page 80 - BBC - The Scientific Guide to a Healthier You

5 it’s dark, it signals for the release of hormones,
such as melatonin, that make us feel sleepy.
If our habits are regular, our brain adjusts to
release hormones at the right time. If they’re
not, we end up in constant conflict with our

natural circadian rhythm. The blue imitation
daylight emitted from computer screens and
smartphones can confuse our SCN further,
Your eye detects light, especially if we’re using our screens at night.
sending signals to the
suprachiasmatic Our brain is tricked into thinking it’s day when
nucleus in your brain it’s not and we end up feeling awake when we
where your ‘circadian
clock’ is housed should be sleepy.

NEVER

BE TIRED

AGAIN

THE SEVEN SOCIAL JETLAG LACK OF EXERCISE CABIN FEVER
Many of us like to treat Long-term tiredness is Light, fresh air and stimulation
CAUSES OF ourselves to a weekend lie-in. associated with too little are all important for brain

FATIGUE AND But going to sleep and waking activity. A University of Georgia health and SCN functioning, so
up at different times during a review of research found 90 being cooped up indoors all the
HOW YOU CAN week can disrupt your per cent of studies agree that time can worsen mood and

BEAT THEM circadian rhythms – the brain’s people who regularly exercise lower energy levels. We’re
natural timing of sleep and report less fatigue than groups particularly prone to this
wakefulness hormone release. who don’t. Exercise increases during the winter. Short-term
This ‘social jetlag’ is associated levels of energy-promoting cabin fever can eventually
with sleepiness, fatigue, bad neurotransmitters, such as become seasonal affective
mood and health problems. dopamine, norepinephrine disorder (SAD). Characterised
A recent study from the Sleep and serotonin. It also resets by depression and feelings of
and Health Research Program the SCN, the part of the brain tiredness, SAD is believed to be
at the University of Arizona that regulates sleep and caused by lack of sunlight
suggests that each hour of wakefulness hormones. And disrupting the brain’s
weekday to weekend lag brings exercise reduces fat stores, production of mood and
an 11 per cent increase in the which seem to be associated sleep-regulating brain
likelihood of heart disease. with long-term fatigue. chemicals, such as serotonin.

Find out about
circadian rhythms
TIP: Avoid weekend lie-ins and TIP: Find forms of exercise that TIP: Pop outdoors every couple
on In Our Time
bbc.in/2ONrA4w late nights, and keep to the fit your lifestyle, rather than of hours, even if it’s just for a
same sleep-wake pattern simply investing in a gym few minutes. It will clear your
during the week. Using an app membership. This way, you’ll brain and may help with
or a tracker to chart your sleep probably be more inclined to lethargy. And eat lunch outside
patterns can help. stick with the workouts. rather than at your desk.