Best Back Exercises to Build Muscle

Pull-ups

Grab the pull-up bar with the palms facing your torso and a grip closer than the shoulder width.
As you have both arms extended in front of you holding the bar at the chosen grip width, keep your torso as straight as possible while creating a curvature on your lower back and sticking your chest out. This is your starting position. Tip: Keeping the torso as straight as possible maximizes biceps stimulation while minimizing back involvement.
As you breathe out, pull your torso up until your head is around the level of the pull-up bar. Concentrate on using the biceps muscles in order to perform the movement. Keep the elbows close to your body. Tip: The upper torso should remain stationary as it moves through space and only the arms should move. The forearms should do no other work other than hold the bar.
After a second of squeezing the biceps in the contracted position, slowly lower your torso back to the starting position; when your arms are fully extended. Breathe in as you perform this portion of the movement.
Repeat this motion for the prescribed amount of repetitions.

Variations:
If you are new at this exercise and do not have the strength to perform it, use a pull-up  assist machine if available. These machines use weight to help you push your bodyweight.
Otherwise, a spotter holding your legs can help.
On the other hand, more advanced lifters can add weight to the exercise by using a weight belt that allows the addition ofweighted plates.

Wide Grip Lat Pull Downs

Sit down on a pull-down machine with a wide bar attached to the top pulley.Make sure that you adjust the knee pad of the machine to fit your height. These pads will prevent your body from being raised by the resistance attached to the bar.
Grab the bar with the palms facing forward using the prescribed grip.Note on grips: For a wide grip, your hands need to be spaced out at a distance wider than shoulder width. For a medium grip, your hands need to be spaced out at a distance equalto your shoulder width and for a close grip at a distance smaller than your shoulder width.
As you have both arms extended in front of you holding the bar at the chosen grip width, bring your torso back around 30 degrees or so while creating a curvature on your lower back and sticking your chest out. This is your starting position.
As you breathe out, bring the bar down until it touches your upper chest by drawing the shoulders and the upper arms down and back. Tip: Concentrate on squeezing the back muscles once you reach the full contracted position. The upper torso should remain stationary and only the arms should move. The forearms should do no other work except for holding the bar; therefore do not try to pull down the bar using the forearms.
After a second at the contracted position squeezing your shoulder blades together, slowly raise the bar back to the starting position when your arms are fully extended and the lats are fully stretched. Inhale during this portion of the movement.
Repeat this motion for the prescribed amount of repetitions.
Variations: The behind the neck variation is not recommended as it can be hard on the rotator cuff due to the hyperextension created by bringing the bar behind the neck

V-Bar Pull Down

Sit down on a pull-down machine with a v- bar attached to the top pulley. Make sure that you adjust the knee pad of the machine to fit your height. These pads will prevent your body from being raised by the resistance attached to the bar.
Grab the v-bar with both hands palms facing in. As you have both arms extended in front of you holding the v-bar bring yourtorso back around 30 degrees or so while creating a curvature on your lower back and sticking your chest out. This is your starting position.
As you breathe out, bring the v-bar down until it touches your upper chest by drawing the shoulders and the upper arms down and back. Tip: Concentrate on squeezing the back muscles once you reach the full contracted position. The upper torso should remain stationary and only the arms should move. The forearms should do no other work except for holding the bar; therefore do not try to pull down the bar using the forearms.
After a second at the contracted position squeezing your shoulder blades together, slowly raise the v-bar back to the starting position when your arms are fully extended and the lats are fully stretched. Inhale during this portion of the movement.
Repeat this motion for the prescribed amount of repetitions.

Variations: The behind the neck variation is not recommended as it can be hard on the rotator cuff due to the hyperextension created by bringing the bar behind the neck

T-bar Row Machine

1. Load up the T-bar Row Machine with the desired weight and adjust the leg height so that your upper chest is at the top of the pad. Tip: In some machines all you can do is stand on the appropriate step that allows you to be at a height that has the upper chest at the top of the pad.
2. Lay face down on the pad and grab the handles. You can either use a palms down, palms up, or palms in position depending on what part of your back you want to emphasize.
3. Lift the bar off the rack and extend your arms in front of you. This will be your starting position.
4. As you exhale slowly pull the weight up and squeeze your back at the top of the movement. Tip: Keep the upper arms as close to the torso as possible throughout the movement in order to better engage the back muscles. Also, do not lift your body off of the pad at any time and refrain from using the biceps to lift the weight.
5. After a second contraction at the top of the movement, as you inhale, slowly go back down to the starting position.
6. Repeat for the recommended amount of repetitions.