Let's get physical: Nine facts about fitness

DOES an activity have to get you out of breath to count as exercise? Do you really have to do half-an-hour a day? Is pumping iron a good way to keep your heart healthy? These are just some of the dilemmas many of us face when working out the best way to get fit. The good news is scientists do broadly agree on the best ways to get fit, they just haven't been very good at telling us what they've discovered.
Let's get physical: Nine facts about fitness