Activities Sports & Athletics Biceps Workouts: What Are Concentration Curls and How Do You Do One? How do you do the perfect concentration curl? Share PINTEREST Email Print Peathegee Inc / Getty Images Sports & Athletics Bodybuilding Training & Routines Basics Health & Safety Baseball Basketball Bicycling Billiards Bowling Boxing Car Racing Cheerleading Cricket Extreme Sports Football Golf Gymnastics Ice Hockey Martial Arts Professional Wrestling Skateboarding Skating Paintball Soccer Swimming & Diving Table Tennis Tennis Track & Field Volleyball Other Activities Learn More By Hugo Rivera Hugo Rivera is a nationally ranked competitive bodybuilder. He has written several books on fitness and bodybuilding, including "The Body Sculpting Bible." our editorial process Hugo Rivera Updated January 18, 2018 Concentration curls are a great biceps workout for stimulating the muscle fibers on the peak of the biceps. What we love about concentration curls is the fact that if performed properly, you can fully isolate the biceps and maximize biceps stimulation. In addition, you can use this exercise for fixing symmetry issues (such as one arm is bigger than the other one), and in addition, you can self-spot yourself as well by using the other hand to help you squeeze out a few more reps. Difficulty Average Time Required 30 to 40 seconds depending on the number of repetitions performed and setup time. What You Need DumbbellsFlat Bench Here's How Sit down at the edge of a flat bench that has a dumbbell right in front of it.Use the right arm to pick it up the dumbbell and place the back of that upper arm on top of your inner right thigh (around three and a half inches away from the front of the knee). Rotate the palm of the hand until it is facing forward away from your thigh. Your arm should be extended at arms length and the dumbbell should be above the floor. This will be your starting position.While holding the upper arm stationary, curl the weights forward while contracting the biceps as you breathe out. Only the forearms should move. Continue the movement until your biceps are fully contracted and the dumbbells are at shoulder level. Squeeze the biceps and hold the contracted position for a second.Slowly begin to bring the dumbbells back to the starting position as your breathe in. Avoid swinging motions at any time.Repeat for the recommended amount of repetitions. Then repeat the movement with the left arm. Tips This exercise can be performed standing with the torso bent forward and the arm in front of you. In this case, no leg support is used for the back of your arm so you will need to make extra effort to ensure no movement of the upper arm. This is a more challenging version of the exercise and is not recommended for people with lower back issues.