Sleep patterns are significantly influenced by the day of the week, the season, and geographic locations, according to a study.

The study, led by researchers from Flinders University in South Australia, is based on data from more than 116,000 adults and over 73 million nights of sleep. The team used an under-mattress device to objectively track sleep duration and timing across 3.5 years, Xinhua news agency reported.

The study finds that sleep is shaped not just by personal habits, but by environmental factors like daylight, temperature, and weekly routines.