Sleeping with the AC on in the summer affects sleep quality, says study
Posted on: 23/Feb/2017 4:14:24 PM
A new study conducted by researchers from the Toyohashi University of Technology in Japan has said that using air conditioners may negatively impact sleep quality despite the comfort we feel in summers, even if the air flow is virtually imperceptible.
They say that, however, high-quality sleep can still be realised if the room temperature is controlled effectively with an AC. The general belief is that having the AC on all night is bad for health. Also, quite a few of us experience chills while sleeping and awakening due to cold temperature.
The research team had people sleep in two bedrooms set to the same temperature using ACs set at different airflow velocities, then made a comparison of the depth of sleep and body temperature control using electroencephalogram (EEG) measurements as well as subjective reporting by the subjects.
Speaking about this, the researchers said, Air velocity of 0.2 metres per second or lower is defined as "insensible airflow", in a sense the person remains unaware of such a low level of airflow. In this study, a comparison was made on the influence of two types of airflow, mean velocity of 0.14 metres per second (general AC) and 0.04 metres per second (customised AC), both at a room temperature of 26 degrees Celsius.
The study compared the correlation between the timing of the airflow starting to blow and body movement, heart rate and waking stage in sleep depth. The results found that people have significantly greater body movements, an increased heart rate and a higher frequency of waking in the room that has the AC with a mean velocity of 0.14 metres per second.
This suggests the general AC may have some influence on sleep, as we discovered that subjects roll over or their sleep depth changes the moment cool air blows out. This study was conducted using healthy adult male subjects.
The research was published in the journal Energy and Buildings.
