To make the exercise more intense, you can perform the following 21 repetitions to increase the intensity of the exercise. For the first seven repetitions, lift and lower the bar from your thigh to the mid point so that your elbows are bent at 90-degree angles. For the next seven repetitions, lift and lower the bar from the mid point almost to your shoulders. To finish the set, perform seven repetitions using the full range of motion. The half curls in this set help to isolate the upper and lower halves of your biceps.
To make the curl more difficult, you can perform a reverse-grip curl which isolates your forearms more but still works your biceps. To perform the reverse-grip curl, perform the same exercise as the curl except start holding the bar with both palms facing your body. You may need to use a lighter weight for this exercise.
The curls primarily work your biceps, with a secondary emphasis on your forearms. The classic biceps exercise is great for building mass in your biceps.
When performing curls, it is important to keep your back straight to avoid straining your back. You can also protect your back by bending your knees slightly and tightening your abdominal muscles. If you have existing lower back problems, consider performing a seated biceps exercise instead, such as seated biceps curl.
You should use caution performing curls if you have elbow or wrist problems. If your grip is too wide or too narrow, you can strain your wrists and elbows. Your hands should be roughly shoulder width apart, with your elbows close to your sides. Your elbows should also remain stable as you lift the weight. You should not lift your elbows up or dig them into your sides.
If you find you are rocking back and forth to lift the bar, you are using too much weight. You should lighten the weight before continuing.
Do not lean back, lear forward, arch your back or swing back and forth to help you lift the bar.
Do not dig your elbows into your sides or shrug your shoulders when lifting the bar.
