Stand with feet together. Perform a forward lunge by taking a big step forward and bending your front leg until your thigh is parallel with the floor and your back knee is about an inch above the floor. Then, rise up and bring your back foot forward a big step and lower into another lunge.
Alternate the leg you step forward with each time, as if walking. Make a total of four to six steps forward, and then reverse the move, taking four to six backward walking lunges.
Want to intensify the lunges? Hold a pair of lightweight dumbells as you lunge.