A Better Back
Scapular retraction,
it's a muscle action that strengthens the middle part of your trapezius, one of your back's biggest muscles.
Pull your shoulder blades (scapulae) together in back (retracting them). The exercise, any variety of row seated using a cable machine; bent-over with a barbell, dumbbells, or T-bar or standing, pulling a cable down to your face
pause, return to the starting position, and repeat. Do one set of 10 to
12 repetitions.