The 2008 Drop a Jeans Size Workout

Combo 5: Mountain Climber/Bicycle

Strength: Bicycle (targets obliques)

Lie faceup on floor with legs extended and hands behind head, elbows out to sides. Bring right knee toward chest and lift head, neck and shoulders off floor, bringing left shoulder toward right knee. Hold here for 1 count, then switch sides, bringing left knee toward chest and right shoulder toward left knee while extending right leg. Repeat, speeding up move.

Put it together:

Mountain climber: 90 seconds
Bicycle: 30 seconds

Mountain climber: 60 seconds
Bicycle: 60 seconds

Mountain climber: 30 seconds
Bicycle: 90 seconds

Before

After