In My Little Pony Equestria Girls: Rainbow Rocks, Pinkie Pie once lifted a girl her age (and her "dog") like, this high:

Pinkie Pie "Slumber party at my house!!!" EG2

And in Friendship Games, the way she shook hands with another girl, I have no idea where all that strength and power came from:

Pinkie shakes Twilight's face vigorously EG3

Does anyone else know about all this?