This is called a Monster Mini-Band Walk, and it might just be my new favorite injury prevention exercise:

The Monster Mini-Band Walk is designed to activate your glute muscles, and more specifically your gluteus medius.  Your gluteus medius is a small (usually weak in most people) muscle that creates hip abduction and external rotation.  Another important function of the glute medius is stabilize the femoral head in the hip joint. 

A strong glute medius is particularly important to prevent the knee to buckle in during different type of activities, which will help you stay away from knee pain.  This is especially important for basketball and soccer players who make a lot of jumps/landings, changes of direction and transitions during their sport practice; and these are all actions that put your knees at risk of buckling in.  Women in general would also benefit stronger glute medius since they have wider hips and their knees are more at risk of buckling in, whatever they do.

Execution:

•  Wrap a mini-band around  your ankles
• Take a wide stance (slightly wider than shoulder width appart)
• Slightly bend your knees
• Take backward steps and make sure you keep your knees out the whole time

You can incorporate the Monster Mini-Band Walks in your warm-ups or even in between your sets of sprints, plyos or lifting.

Give it a shot!