2. Breathe in Deeply at a Brooklyn Yoga Class, New York, USA

New York's parks are ideally suited for walking off pounds piled on with enormous American breakfasts, but if you're looking for a proper workout to build up perspiration, head to one of Brooklyn's many yoga studios, like Shambhala Yoga and Dance in Prospect Heights. Classes are suited to all abilities and a workout is a good excuse to enjoy a treat at nearby Junior's, the world-famous cheesecake place. For an even more energetic workout, try the famous Church Street Boxing fight gym. Offering standard boxing, jiu-jitsu and muay thai, the gym is a mere half block from City Hall Park, where you can relax and lick your wounds afterwards.