Another common mistake is lifting the butt off the seat while bringing the arms down. Your biceps should be doing all the work. If you are unable to lower the handles and bring them back up again without lifting the butt off the seat, then you should be using lighter weights.
Double check that the seat is adjusted properly to your height. If the seat is too high, you will lean into the preacher curls, stealing the work away from your biceps.
Concentration Curl
Concentration curls work the biceps while keeping the upper arm stable.
To perform correctly, sit on a chair or bench with knees placed somewhat wider than shoulder-width apart. Feet should be flat on the floor.
Lean slightly forward, but keep back as straight as possible.
Let your right arm hang straight down from the shoulder with the elbow slightly bent. The arm should be touching the inside of your right leg directly above the knee.
Brace your arm against your leg as you raise the elbow to the front of the shoulder. Then, lower the dumbbell until your arm is fully extended. Palms should be facing up and each contraction should be carefully controlled.
Hammer Curl
Start standing with feet shoulder-width apart. Bend the knees slightly while keeping your back straight and shoulders relaxed. Contract the abdominal muscles to support your back.
To perform hammer curls, keep elbows fixed at your sides with palms facing each other. Curl the dumbbells up, the same way you would for a regular dumbbell curl.
Ideally, the flat of the dumbbell, should come close to touching the shoulder of the lifting arm at the top of the rep. Keep the upper arms vertical with elbows locked in place. Do not rotate wrists as you lift the weight. The movement should mimic a hammer's swing.
More: Why Women Should Lift Weights
Pull-Ups and Chin-Ups
Pull-ups and chin-ups force your arms to lift your own body-weight. It is the best strength training you can do for your entire upper body, though you'll definitely see some improvement in those biceps.
If you're a beginner, even a single pull-up or chin-up can have a significant impact on your muscle growth.
The two exercises feature similar movements, but pull-ups feature the palms facing away from the body while chin-ups have the palms facing you. Chin-ups work the biceps more while pull-ups involve more back muscles.
In order to perform this exercise, you'll need a pull-up bar.
Start each rep from a dead hang with straight elbows, then pull the body upward until your chin clears the bar. Breathe in at the bottom of each rep before pulling yourself up. Keep eyes focused upward toward the bar you're pulling yourself up to.
Keep legs bent and feet crossed. Hips should be in line with the torso.
Tip: Put the bar close to your fingers, rather than the palm of your hand to minimize callus formation.
Common Mistakes
Many beginners pull their shoulders forward as they lift upward. This puts extra strain on the shoulders and back. It's better to lead with your chest up and keep shoulders back.
Additionally, it's better to start each rep from a dead hang. Partially lowering the body may make it easier to pull yourself back up but it cheats you of a great workout.
More: Infographic: Your 30-Minute Bodyweight Workout Routine
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