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Your back is characterized by three smaller muscles: latisimus dorsi, rhomboids (upper/middle back), and erector spinae (lower back). These three muscles, along with smaller supporting muscles deep beneath the skin's surface, play a huge role in almost everything you do, from swinging a golf club to sitting at the dinner table. Erector Spinae: Runs along the lower part of the spine, hereafter referred to as the lower back. Your lower back supports your upper body, extending your spine and flexing it to either side, a part of almost every activity imaginable.http://www.shapefit.com/training-lowerback.html

Lower Back Exercises - Hyperextensions
Lower Back Exercises - Smith Machine Good Mornings
Lower Back Exercises - Barbell Good Mornings
Lower Back Exercises - Dumbbell Good Mornings
Lower Back Exercises - Lying Back Presses

Middle Back Exercises - Barbell Rows
Middle Back Exercises - One Arm Barbell Rows
Middle Back Exercises - Two Arm Dumbbell Rows
Middle Back Exercises - Two Arm Hammer Dumbbell Rows
Middle Back Exercises - Lying T Bar Rows
Middle Back Exercises - Incline Bench Dumbbell Rows
Middle Back Exercises - Single Arm Dumbbell Rows
Middle Back Exercises - Reverse Grip Bent Over Rows
Middle Back Exercises - Seated Cable Rows
Middle Back Exercises - Smith Machine Rows
Middle Back Exercises - T Bar Rows
Middle Back Exercises - Machine Rows

UPPER BACK EXERCISES

Exercise Advice: Grab a V Bar and place it on a pullup bar so that the handles of the V Bar are hanging over the sides so that you can grip it with both hands and support your body weight. Simply pull your body up so as to try and touch you chest to the pullup bar. Return to the start position and repeat until failure.

Back Exercises - Reverse Grip Pulldowns
Back Exercises - Pullups
Back Exercises - Straight Arm Pulldowns
Back Exercises - V Bar Pulldowns
Back Exercises - V Bar Pullups
Back Exercises - Wide Grip Pulldowns
Back Exercises - Wide Grip Rear Pulldowns
Back Exercises - Wide Grip Pull Ups