Shake It Off Lyrics

Lyric discussion by ynotbor 

Cover art for Shake It Off lyrics by Wilco

I have listened many many many times to this song and to this album. I am still undecided about the meaning of this one. The imagery is terrific. The chorus is inspiring. The delivery is superb. But what concerns me is - is it a good thing that he is shaking it off? Upon further consideration, I am still not sure. Maybe the singer is sad that he's gotta shake it off. What is spoiling his heart? Sleep? His dreams? If anyone has any insight, I would like to hear it.