The bent over row is an excellent exercise for the development of a wide and powerful back, strong deltoids erector spinaes and a well sculpted upper back. 

Muscles Worked During Bent Over Row  

Target Muscles

• Upper back
• Deltoids
• Erector spinae

Synergists 

• Rhomboids
• Latissimus Dorsi
• Teres Major
• Deltoid, Posterior
• Trapezius, Middle
• Trapezius, Lower
• Infraspinatus
• Teres Minor
• Brachialis
• Brachioradialis
• Pectoralis Major, Sternal

Dynamic Stabilizers

• Triceps, Long Head
• Biceps Brachii

Stabilizers

• Gluteus Maximus
• Adductor Magnus 
  
• Erector Spinae
• Hamstrings

How to Properly Perform the Bent Over Row

1. Make sure your head is parallel to the ground and centered over your shoulders.
2. Bring your chest up.
3. As you bring your chest up, your shoulders must relax and not go up. Therefore, relax your shoulders down and back.
4. Tighten your abs by pulling your belly button to your spine.
5. Align your knees with your second and third toes.
6. Make sure your knees are not locked. There must always be a slight bend in them.
7. Stand with your feet spaced comfortably apart (usually hip width).
8. Stand with your body weight placed at the mid points of your feet.  

1. Bend your torso over, keeping a natural arch in your spine, keeping your knees slightly bent.
2. Keep your abdominal muscles tight, shoulders back and chest up.
3. Take a big breath before pulling the weight to your chest.
   
4. Breathe on the floor between reps.
5. Don’t extend your hips too much. Your back shouldn’t rise much higher then where it was at the start of the Barbell Row
6. Pull the weight up to your lower chest (xiphoid process) in a steady movement, while focusing on bringing your shoulder blades together. Stop just after your elbow joints are in line with your shoulders and reverse the motion back down.
7. Under control, lower the weight, stop just before your elbow joints are straight and reverse the motion back up.
8. Repeat 

The Importance of Building a Strong Back

The back is a very large muscle group which should be trained. If the back is not trained with the same intensity and frequency as the chest muscles, muscular imbalances will occur and injury is much more prevalent.

Tips for Maximizing the Muscle Building Effects of Bent Over Rows

• Torso may be kept horizontal for stricter execution.
• Knees are bent in effort to keep low back straight.
• If low back becomes rounded due to tight hamstrings, either knee should be bent more or torso may not be positioned as low.
• If low back is rounded due to poor form, dead lift weight to standing position and lower torso into horizontal position with knees bent and back straight.
• A shoulder width or underhand grip can increase lat involvement by emphasizing shoulder extension over transverse extension.
• Don’t pull with your hands. Pull your elbows to the ceiling. Try to make your shoulder-blades touch & open your chest.
• The bar starts on the floor on each rep. Don’t overdo the hip extension.
• Don’t try to hold the bar against your chest.
• Don’t try to return the bar slowly to the floor.
  

Common Errors While Performing the Bent Over Row 

• Bar Too Far Away. Keep the bar close to your body. Put the bar over your feet, straight under your shoulder-blades.    
• Back Going Vertical. It’s not a Deadlift. Your upper-back should do the work, not your hips. Lower the weight if you extend your hips too much.   
• Dropping the Chest. You’ll drop your chest to meet the bar when the weight gets heavy. Lower the weight when this gets excessive.   
• Extending the Knees. Use hip extension on the way up, but no knee extension. Keep your knees unlocked but straight.

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Variations are intended to work different subgroups of muscles, or work the same muscles in slightly different ways. There are plenty of variations to the exercise. Some other variations include:

• Dumbbell Bent Over Row. Same movements as as detailed above.
  
• Pendlay Row. Pendlay Rows involve arching of your upper-back.
• Reverse-grip Row. Using an underhand grip. Works biceps more.

These exercises will help develop a big and powerful back when used with the bent over rows:

• Deadlifts. Deadlifts are a great overall exercise for putting on overall body mass and fantatic for putting on lots othick back muscle.
  
• Machine Seated Row. This exercise works the entire back. Here are just some of the muscles this great exercise works, Erector Spinae, Trapezius, Rhomboids, Latissimus Dorsi, Teres Major, Teres Minor, Rear Deltoid, Posterior,  Infraspinatus, Brachialis, Pectoralis Major, and Sternal 
• Lat Bar Pulldown. Lat pulldowns work the lats and upper back. Here are just some of the muscles this great exercise works,  Trapezius, Rhomboids, Latissimus Dorsi, Teres Major, Teres Minor, Rear Deltoid, Posterior,  Infraspinatus, Brachialis, and Pectoralis Minorl
• Hyperextensions. Hyperextensions target the erector spinae, while indirectly working the gluteus maximus, hamstrings, and adductor magnus.