IPhone 4S/5 videos are blurry when sent through mms and email, why?

My frend took some fan cams at a concert and when she sent them through text they came out extremely blurry. She sent them through email but it still came out really blurry, so blurry you can't see the faces of the band members. Is there a reason why? She has an iPhone 5 and I have an iPhone 4S. I can't send my fan cams to her, through email, either, the file is too big. Is there a solution or am I *** outta luck?

I've used the mailVU app on my iPhone. The quality is good and the app is free.