Make sure whatever fluid you drink before and during exercise is icy cold.

Make sure whatever fluid you drink before and during exercise is icy cold.

A team led by David Jones, professor of sport and exercise sciences at the University of Birmingham, England, had eight men cycle to exhaustion in 93-degree Fahrenheit heat.

They found that those who drank cold fluids biked seven minutes longer than those given warm drinks.

They also had slightly lower temperatures and heart rates, and drank 1.4 quarts of fluid compared with 1 quart of room-temperature water.

Paradoxically, after exercise, drinking cold water might be worse for hydration.

"It satiates you more, so you drink less," says co-author Toby Mundel. That's when you should drink something at room temperature.