Hi,
Try out this exercise for greater hip strength and range of motion...

1 leg hip extension

Too often I see athletes with not enough strength or range of motion around the hip joint.  What happens you ask?...well usually overuse in other joints.  If you can't get the range of motion from the hip you will often use your back or your knees to get the movement you are striving for.  That will lead to possible injury in those areas and also will be less than optimal for power or speed.  Bottom line- you need your hips for power and proper, functional movement patterns!  So...check out the video for an exercise that can get you on the path to functional, powerful hips!