I was a music major in college and studied the cello briefly as part of the curriculum. It is physically wearing; one needs unusually strong fingers to do it right. But to play like this guy you need I-can-stab-you-through-the-heart-with-my-index-finger secret-agent strength fingers. Even the pinky.
You've heard the melody before, it's often borrowed, but Paganini wrote this originally for the violin not the cello, which makes this performance all the more impressive.