ABC News visited a cryotherapy center to try out a sub-zero full-body machine. — -- What does it feel like to have your body immersed in sub-zero temperatures? I was soon going to find out. I ...

The human body is a marvel of engineering, but it’s a machine that requires maintenance and repair. At times, that means trying to replace parts lost to injury or illness. The oldest known prosthesis ...

Every night, millions of people stop breathing without knowing it. Not once, but sometimes hundreds of times. Their remedy? A mask, a hum and the steady whisper of pressurized air. It's not glamorous, ...