For fitness purposes we can roughly divide the body into three sections: the lower body (legs), the core (abs), and upper ...

Beth Skwarecki is Lifehacker’s Senior Health Editor and has been writing about health, fitness, and science here since 2015. Beth was the recipient of the 2017 Carnegie Science Award in science ...

I work with athletes and non-athletes of all sorts in my role as a personal trainer and yoga teacher and one of the most common complaints I hear is nagging stiffness and soreness in the upper back.