Pullups work the shoulder muscles, and the trapezoid is an essential part of that muscle group. Pain is usually a sign of a problem, and when it happens during a pullup, it may signify an overuse injury to the trapezius muscle. How you handle the injury will affect your recovery. Severe pain in the shoulder should be examined by a doctor to rule out serious damage.
The trapezius muscle starts at the base of your skull and works down the back to form a triangle, ending around the mid back. It helps to support the arms and the scapulae, or shoulder blades. A pinch in your shoulder is actually pain in the upper fibers of the trapezius. When you do a pullup, you are getting part of your power from this muscle. If you feel pain in your back or shoulders, you may be trying to do the pullup before you are ready or using improper form.
Proper technique when performing a pullup can help avoid damage to your trapezius muscle. Fitness expert Stew Smith explains on Military.com how to do a pullup. Grab the bar with your palms pressing downward, similar to how you grasp handlebars, hands shoulder-width apart. Pull upward until your chin is just over the bar. Slowly lower your body back down. If you drop too quickly, you risk straining the muscles.
Working Up to a Dead-Hang Pullup
Pullups are difficult. You are lifting your entire body weight, and that is not something you should do before you are ready. If you are not used to doing pullups, start by placing the bar four feet off the ground. This is known as an assisted pullup. You grip the bar as if doing a full, or dead-hang, pullup, but let your legs take some of the weight. Once you can successfully do 10 of these with little help from your legs, move to a full pullup. Do one or two at a time. This will protect your trapezoid from tearing or strain. If you feel pain, stop. Rest a few days and then try again.
Treating the Pain
Pain in the trapezius is probably a strain or pull. Apply ice to the affected area as soon as possible. Leave the ice in place for 20 minutes and reapply three or four times a day for three days. If your back or shoulders are still sore, try alternating heat and ice for 20 minutes each. This may help loosen the muscle. You should not exercise, and especially avoid pullups, until you are pain-free for a week. Your doctor can advise you on the most effective pain medication for you.