Leverage iso Row, also known as the machine row is an exercise for your entire upper back. It primarily works the lats and the rhomboids. And it will also work the middle and lower traps, the erector spinae in the lower back, and the teres major of the sides of your back. The shoulders and the biceps are worked as secondary muscles. The glutes and hamstrings also act as stabilizers.
The row is a great exercise to strengthen and build thickness in the back muscles. Rows can also be done with a cable or with free weights. The machine version has some benefits over free weights. It is easier to learn and the machine keeps you in a strict form. Also, free weight rows often require you to be in a bent-over position. This might put a lot of stress on your lower back, and cause back problems when done with less than a perfect form.
The downside of the machine is that it less of a functional movement, and it neglects many smaller stabilizing muscles that being worked when you use free weights.
Do not rock the torso back and forth. Moving the torso will shift the weight from your lats to the lower back. Keep the chest pushed against the support pad throughout the exercise.
Focus on your back muscles, you should feel this exercise working your lats and back. Don't turn it into a curl, where the movement is done only with your arms. Think of your arm as merely a hook to connect the resistance to your lats and mid-back muscles.
Keep your back straight, chest up and the shoulders pulled back and down. Do not hunch the shoulders forward or round your back, if that happens it is usually an indication you are using too much weight.
Move the handles in a slow and controlled manner. It is very easy to use momentum for this exercise, and although it will feel easier, your muscles will work less effectively, and you will be more likely to break your form.