The style features verses that are slow, sometimes speeding up, but ending with a rallentando and often a fermata, then going into a chorus that begins slowly (sometimes very slowly) with a gradual accelerando that builds in volume and tempo to a frenetic pace. Then rinse and repeat.
Example: Дорогой длинною
This is distinct from this kind of dance song (a hora?), which starts quiet and slow but then builds throughout to a feverish pace and volume over the course of the entire piece.