Nighttime smartphone use drains workers' energy
In a pair of studies surveying U.S. workers, researchers from Michigan State University found that people who monitored their smart phones for business purposes after 9 p.m. were more tired and less engaged the following day on the job.
For the first study, the researchers had 82 upper-level managers complete multiple surveys every day for two weeks. The second study surveyed 161 employees daily in a variety of occupations, from nursing to manufacturing and from accounting to dentistry.
In both studies, the surveys showed that nighttime smartphone usage for business purposes cut into sleep and depleted energy from the worker the next day in the office. The second study compared smartphone usage to other electronic devices and found that smartphones had a larger negative effect than watching television and using laptop and tablet computers.
The main disruptor with the smartphone seems to be the “blue light” that’s emitted from the phone. Blue light is known to hinder melatonin, a chemical in the body that promotes sleep.