Effects of heat and cold prior to a hamstring stretch

I am a 3rd year PT student about to commence my dissertation. I am seraching for literature regarding the effect of hot and cold packs when applied to the hamstring muscle group prior to a hamstring stretch on flexibility. Has anyone come across any interesting findings? Any help would be greatly appreciated!

Hi, I've just recently finished my research proposal on the same subject and have loads of references. If you leave an email address I'll send you some info.

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