Armscyes and arm movement

[mala_14]

I've noticed that I don't have the greatest range of motion in my historical dresses. I can't seem to lift my arm past the shoulder. I'm pretty sure that I've read somewhere that making the armscye smaller or tighter under the arm helps increase range. I do have a bit of space in the underarm on my late Victorian bodice pattern that I could take in. What do you guys have to say on the subject of arm movement? Thanks!