Funk and Steve Delaney of PhysioMed http://www.phisiomed.ca
take you through 3 stretches to help with hip flexibility, knee problems and bad lower back.
Do these stretched BEFORE you train and after a quick warm up to open and loosen up the hips.
I used these stretched to help me win my first Pro Muay Thai fight. If I did not use these stretches, there is NO way I would have been able to kick at all (I have tight hips)