Here is a 5-minute routine you can do when you wake up, to loosen up tight hips. These poses stretch the groin, hip flexors, outer hips and glutes. If you suffer from lower back pain, this is the vid for you.
Good alignment is important so if you're super tight, support yourself on blocks where you need them while you're working to improve your flexibility.
You can download the full series for tight hips here: Yoga 15: Hip Strength and Mobility
Photo credit: @fionapeters