Researchers at the University of Tsukuba have discovered that the so-called "multi-task exercise," which combines cognitive activity with physical movement, enhances sleep quality in older women by ...

Lindsey Ellefson is Lifehacker’s Features Editor. She currently covers study and productivity hacks, as well as household and digital decluttering, and oversees the freelancers on the sex and ...

Tsukuba, Japan—During deep sleep, brain wave amplitude increases, and "δ (delta) power," a key objective indicator of sleep quality, is observed; higher delta power corresponds to deeper, more ...