Sleep Flashcards
Define…
1) sleep latency
2) sleep efficiency
3) sleep quality
1) Time taken to fall asleep
2) (sleep time/time in bed) * 100
3) subjective experience of sleep
What is the behavioural definition of sleep?
a period of restorative immobility of greatly reduced responsiveness
What is the physiological definition of sleep?
a dynamic ‘stage like’ process showing distinctive electrophysiological structure
What are the 4 theories of sleep and who proposed them?
ADAPTATION : growth and repair
ENERGY CONSERVATION : reduced metabolism
INACTIVITY : better survival chance
BRAIN PLASTICITY : synapse regeneration
- Siegal (2005)
What is the effect of sleep deprivation?
impaired immune function and altered hormone and metabolism responses
What are 3 commonly used methods of measuring sleep?
> Polysomnography (EEG, EMG, EOG)
Actigraphy
Questionnaires
Summarise how polysomnography can be used to assess sleep
sleep states are identified through electrophysiological patterns, which are used to create a hypnogram
Summarise how actigraphy can be used to assess sleep and give a drawback of using actigraphy
a wrist worn device measures movement and light intensity during the night to characterise sleep patterns
X Doesn’t measure sleep stages
What is the most commonly used sleep questionnaire and what are the pros and cons of using it?
the Pittsburgh Sleep Quality Index (PSQI) which measures sleep quality and insomnia.
+ well validated in many populations
X not a diagnostic tool
What is the definition of good quality sleep and who the fuck said so?
> 85% sleep efficiency
sleep latency of <30 mins
waking up once or less a night
- National Sleep Foundation (2017)
What is the definition of insomnia?
give a reference
difficulty initiating / maintaining sleep despite adequate chance
non-restorative sleep
occurrence 3 x a week for a month
- American Academy of Sleep Medicine (2004)
Describe the two processes of sleep in “Borbely’s two process model”
S - sleep propensity is dependent on the preceding duration of wake
C - sleep propensity is controlled by pacemakers and varies over 24 hours
What are the three broad categories of processes that influence sleep behaviours?
> Sleep homeostasis
Circadian rhythm
Arousal system
Describe sleep homeostasis
adenosine (NT) builds up in the basal forebrain during wake, informing the brain that it should sleep
More PA = More adenosine = Greater sleep drive
How does a short sleep duration affect sleep propensity and which process of Borbely’s model does this involve?
Short sleep duration increases propensity to sleep (S process)
- Borbely (1982)
What are circadian rhythms controlled by?
exposure to light which stimulates the SCN
Describe the procedure and results of a piece of research into the effect of manipulating circadian rhythms on sleep
Petit et al (2014)
exposed 16 highly trained athletes to a 5h phase advance in a lab setting.
Sleep efficiency dropped dramatically.
X V. large individual differences, so not universal.
How does the arousal system affect sleep/wake behaviours?
the ascending reticular activating system promotes cortical arousal (wake)
How do active arousal systems affect an athlete in …
a) performance
b ) sleep
??
a) can be beneficial to be hyperaroused
b) results in high sleep reactivity which can lead to sleep disruption
What is sleep reactivity?
the extent to which an individual is disrupted in sleep by outside factors (noise, touch, different environment)
Describe a piece of research into sleep reactivity and sleep behaviours
Drake et al (2004)
those w/ high sleep reactivity had greater sleep latency during a sleep lab visit (new environment)
What effect does elite sports have on the three sleep processes of sleep homeostasis, circadian rhythm and arousal system?
elite sport CHALLENGES these processes, BUT, doesn’t necessarily DEGRADE them
Outline 2 pieces of research into how sleep can affect sporting performance
> Silva & Paira (2016)
top ranked intl gymnasts scored higher on PSQI (poorer sleep), however, most ‘sleepy’ athletes performed worst.
> Leger et al (2008)
best performing team in a long haul sailing race “banked” sleep prior to the race
How does participation in high level sport influence PSQI score?
athletes score higher on PSQI than non-athlete controls
- (Bender et al, 2014)
Outline the protocol and findings of Juliff et al (2015) into the effect of high level competition on sleep
~300 Australian olympic athletes completed PSQI leading up to London 2012.
64% reported disturbed sleep prior to comp, mainly due to nerved/worry.
Performance quality was not affected by sleep quality/quantity prior to comp.
Individual sports reported higher sleep disturbances than team sport, due to greater responsibility and pressures
- (Juliff et al, 2015)
Which stage of sleep is V.importante for psychophysiological restoration?
stage 3
How must you approach improving athletes’ sleeping behaviours?
give realistic and practical guidelines
Why is it important that you manage athlete sleep expectations?
reduce worry associated with sleep as psychology and cognitions can hugely affect sleep
How can you fix and individual who is spending too long in bed trying to sleep and has poor sleep efficiency?
reduce sleep window (opportunity), increasing sleep drive and therefore shortening sleep latency
Working off the S process of Borbely’s model.
