It's common to feel tired and apprehensive on a Monday morning, and that can be especially true after a big weekend.
New research has mapped how people's quality of sleep changes throughout the week, and has found patterns between fatigue and behaviour.
It's estimated around one billion people worldwide have obstructive sleep apnoea (OSA), a condition that impacts their quality of sleep.
Australian researchers have found this underlying condition is more prevalent on weekends than on weekdays, and they have labelled this phenomenon — 'social apnoea'.
It can affect anyone, even if you don't typically show symptoms of OSA during the week.
So why is that the case?
'Social jet lag'
Professor Danny Eckert, a sleep health expert from Flinders University, was one of the lead researchers in the study that was published in the American Journal of Respiratory and Critical Care Medicine.
He described social apnoea as a kind of "social jet lag", a feeling that can arise after the weekend, when our behaviours often differ from those on weekdays.
"We know that people who smoke tend to smoke more on the weekend. We know that people who drink tend to drink more on the weekend," he told SBS News.
"They are two sort of lifestyles or social factors if you like, that are very influential in the way we sleep and breathe."
Eckert said another key change in weekend behaviour is that our sleep patterns often change, which can cause problems with our sleep quality and overall mood.
People who sleep in on weekends were found to have a 50 per cent higher risk of developing a sleep disorder, according to the study.
"Our circadian rhythm, or our body clock, is slow to move; it takes several days to adjust," he said.
"So if we suddenly change our sleep timing, and we've all experienced this at different times with jet lag and these kinds of things, we're sleeping out of whack from what our body wants us to."
What are the long-term effects?
Weekend surge in sleep-disordered breathing may heighten the risk of serious health conditions, according to the research.
This includes heart disease, depression, dementia, and extreme fatigue.
The research found people under 60 and males were two groups more likely to suffer from social apnoea. While the exact reason is unclear, Eckert said it's likely due to behavioural factors.
"We know that men tend to be drinking more alcohol than women and perhaps they're having later nights and going to sleep after women," he said.
"We also know that men get sleep apnoea more, so they are more prone to 'social apnoea' in the first place."
Eckert said beyond seeking clinical treatment for sleep apnoea, there are some lifestyle changes you can make to combat social apnoea. In particular, going to bed and waking up at consistent times can help establish a healthier sleep pattern.
"If people are feeling tired during the day, having some trouble staying asleep, or maybe they are waking up with morning headaches, maybe they're being told that they snore loudly; these are all warning signs that you may have sleep apnoea, and it's worth having a conversation with your GP."
