None of them have any validate or published data to supp;ort claims
Ability to detect sleep stage based on movement not viable..
Brain waves … eye movement most important
Cant do it on basis of movement alone. If haven’t moved for a whiel probably I deep sleep – in some people a jerkign thing that happens in dreaming or REM person.
No one has ever published any ata regardin these apps.
Don’t tell you whats in the app – all commericl in confidence to impossible to test them
Have put actigrpah=hs on peoel in lab .. concluded that they were crap.
We use them for determining how much sleep someone has had but not stage of sleep, and how much they wake up, and how disrupted. By and large when people are asleep they don’t move.
When they get to an arousal, htat’s probably the end of a REM period. And wake up briefly roll over and go back to sleep.
Produce nice looking sleep plots …
IF look at process of how long it takes to wake from sleep – if wake from deep sleep takes longe for brain to get going than if wake from REM. At end of the night hardly getting any deep sleep anyway.
Might make a difference for 5 – 10 minutes.
The placebo –
Neither a fan or a critic – jury is out.
Most will wake from REM or stage 2
If do go to bed before midnight — more likely not to have been drinking alcohol and a whole host of other factors
Fi a sleep period is 4 hours , most of that will be SwS
IF go to bed early will get more REM> After 4 – 5 hours of SwS, you have time left over for …
REM memory betterl earning, and if wake up won’t feel sleepy.
Between 9 and 12
If go to bed at 6 am .. will find a fair degree fo REM at that stage.
Idea of plotting your bed time by going back 90 minutes cyckewComplete rubbish – too variable both within people and between.
After 90 – 120 min after going to sleep, you will be in REM sleep. By the time you have 3 cycles could have be out by 1.5 hour
When you wake in the morning you have a better than 50% chance of waking from a REM period … unless you need
If you need an alarm clock to wake up probably sleep deprived .
Go to bed early enough to wake spontaneously and probably getting enough sleep. Except if have depressive illness wake after 4-5 hours and don’t feel good, cant maintain sleep.
Fi don’t want to get out of bed early in morning and getting enough sleep something else going on eg hate your job, or could be depressed, or terrible commute. Not wanting to get out of bed often blamed on sleep often due to other lifestyle issues.