In order to show off all that toned muscle you've been building, you'll also need to trim down the fat. The easiest — and healthiest — way to lose weight is through a consistent cardio program and a healthy diet. If you're hoping to get shapely arms like Kate, maximize your cardio efforts by picking arm-emphasizing workouts. Kate is a regular on the ski bunny and is also quite the rower — both of these activities require a lot of upper body movement.
Can't make it outdoors? Just hop onto your gym's elliptical or rowing machine.