The subscapularis muscle is very important for the Internal rotation of the humerus. The internal rotation supports the upper arm during abduction and adduction.
There are some band exercises that can help you strength the Subscapularis muscle...
1. Internal Rotation - uses medial internal rotation
2. External Rotation - uses lateral external rotation
3. Front Row - You have you hand up in front of you and with your arm extended pull back the band.
4. Side Row - You're side to the band with your hand facing the hip, pull down toward your body. (ADDUCTION)
THIS IS NOT A FAIR QUESTION NBME!!!
What puts internal rotation over adduction? Subscapularis muscle does both