By Jamie Leach
Any type of cardio is great for burning calories, and this is what's most important when you're trying to lose weight.
Sit-ups and crunches are the stereotypical exercises to work out your abdominal muscles.
Bicycle crunches work out your abs like regular crunches, but the extra movement with your legs challenges more muscles and burns more calories.
Planks also work out your abs but there's no motion required—instead, you're working the muscles out by keeping them isometrically contracted.
The mountain climber is a great bodyweight exercise to perform following planks.
While still facing the ground after doing a plank, switch to mountain climbers, which target many muscles throughout the body while burning calories.