Sign up for CNN’s Fitness, But Better newsletter series. Our seven-part guide will help you ease into a healthy routine, backed by experts. A systematic review of ...

Dr. Mark Harper recalls his first cold-water swim in the south of England 20 years ago. It was August, but the initial jolt from the plunge took his breath away. The shock to his system lasted a ...

Although it's not a hard and fast rule, marine animals that live in cold climates tend to grow larger than their warm-water counterparts. According to a new study, such may have even been the case ...

When seawater gets cold, it gets viscous. This fact could explain how single-celled ocean creatures became multicellular when the planet was frozen during “Snowball Earth,” according to experiments.

The massive snowmelt means our waterways are running fast and cold, but what really happens to your body when you jump into frigid water? The physical reaction to entering cold water is called "cold ...