Dynamic exercises are generally better than static stretching when it comes to warming up. Not only do they loosen things up without harming performance, but the right moves can even activate muscles and enhance performance. Here's one to try out.
Around the World
This is very useful for the external and internal rotators of the hip, which tend to have some residual kinks no matter how well you warm-up. This will also loosen up the knees by acquainting them with the extended ranges that may or may not be encountered in the upcoming lifting session.
Bonus: They'll also give the lats and trunk a good stretch.
related posts
Athlete Lean, Athlete Strong
The fastest and most effective way to get ripped is to train like a power/speed athlete. Here's your complete program.
Smart Training 2
Dr. Ken Kinakin, much like Dr. Mike Leahy, knows your pain. In fact, he's made a living off of it. The doc is one of the best in the world at devising training protocols to help make you injury-proof. Yeah, he likes bodybuilding and powerlifting routines, too, but when it comes to figuring out how to fix what ails ya', he's one of the best.
Tip: Do This Exercise to Sprint Faster
Want to run like a cheetah? You need more than squats, deadlifts, and box jumps. You need this horizontal force exercise.
My Top 5 Single-Leg Exercises
You don't like single leg movements? Eric Cressey shows you your argument doesn't have a leg to stand on.