Little or no extension

[Floger]

My swing feels tight, not loose a free swinging like a practice swing or range. Its like I am hitting AT the ball and not swinging THRU the ball. I feel tense and tend to pull my arms across my body to the left because I am trying to keep my armpits connected through the swing to prevent slice, etc. I am rotating toward the target, so I feel good about that. My finish has my chest facing my target.

Is there a drill or swing thought to prevent this alligator arm syndrome? I tried imagining swinging to first base, to prevent the cutting across my body and try to swing more toward the target and let momentum bring me around to finish, but just doesn't seem to work.

Thanks