It's tight under the arms.
'Ascelle' — 'a-SHEL-le'. Three syllables, stress on second. 'Sc' before 'e' = 'sh'.
Describing tightness in the armhole area — one of the most common fit problems with jackets and blouses. Specific and helpful feedback.
'Stringere' = to tighten. 'Mi stringe' = it's tight on me. 'Sotto le ascelle' = under the armpits. 'Ascella' (armpit) is an important body part word in Italian tailoring.
Non riesco ad alzare le braccia.
I can't raise my arms.
Describing the functional limitation caused by tight armholes
L'ampiezza sotto braccio è troppo stretta.
The width under the arm is too narrow.
Technical tailoring description
Tira quando mi muovo.
It pulls when I move.
Describing the dynamic fit problem
The 'forchetta della manica' (sleeve pitch) is a key tailoring term in Italian. It refers to the angle at which the sleeve is set into the armhole. Getting it right is what separates master tailors from average ones.