Madonna works hard to keep up her fit form - and rarely takes a day off from exercising. "I mix it up - Pilates, gyrotonics, yoga," says the pop superstar. "I do it six days a week, with Sundays off... Actually Sunday is a day of horse riding. There's no such thing as a day off." She does admit, however, to spoiling her diet once in a while by having "fat days." "I run longer on the treadmill and don't eat as much the next day, so then it evens out, but I'm sure it's all in my head."