Working your lats unilaterally and with your chest supported on a bench isolates them as best you can.
How To Do It:
Two steps to building a bigger set of wings.
1. LIE CHEST DOWN (You may need to incline the bench.) Row the left-hand dumbbell. Now perform five rows on the right arm while holding the isometric.
2. ON YOUR LAST REP of the row, hold the top position and lower your left arm. Now perform rows on the left side while you statically hold up the right arm.
QUICK TIP: Pinch your shoulder blades together at the top of each rep.
Did You Know?
Making one lat work isometrically keeps it under tension, and when that tension is released it causes a cascade of fresh blood to the muscle that supports a pump and, by association, new growth. Meanwhile, you still get the benefits of training through a full range of motion by performing normal reps in the same set.