A number of injuries and medical conditions that affect other parts of the body can lead to shoulder and collarbone pain while you're exercising. The chest and shoulders share a common nerve supply and are connected to other body parts with common tendons and ligaments. Impact injuries directly to the shoulders or clavicle also can lead to discomfort when you work out and should be treated as an emergency.
Find and Treat the Source
If you haven't had any impact injuries to your collarbone or shoulders, consider other sources that may be causing the pain. Heart attacks often cause referred pain that you feel in your shoulders. Gallbladder disease causes pain in the right side of your shoulder and collarbone. Chest pain from a bout of pneumonia may irritate your shoulders when you exercise. If you tend to experience heartburn after eating, the esophageal backup may cause your shoulders to ache if you exercise too soon after eating. Excessive coughing can cause you to pull a muscle in your shoulder.
Repetition
Repetitive movements such as throwing a ball or swinging a racquet can cause your rotator cuff muscles to become inflamed or strained. Referred to as rotator cuff tendonitis, you may need to limit use of your arms while the area is inflamed and apply ice to decrease the swelling. Joints become worn out over time and leave you with bursitis or osteoarthritis in your shoulder sockets, causing pain with movement. Rest and limited use alleviates shoulder and collarbone pain due to wear and tear.
Treatments
You need to be careful about placing your arm in a sling to alleviate the pain you feel when moving, according to the American Arthritis Society. Immobilization can cause stiffness that will take much more extensive therapy to resolve. Instead, tie up your arm so that it rests on a platform or pillow away from your body. Range-of-motion exercises are most effective for alleviating stiffness and rehabilitating your sore shoulders.
Prevention
Prevent additional pain by warming up your shoulders prior to exercising. One of the most effective exercises for loosening up a tight shoulder joint is to hold a light free weight, about 1 to 2 lbs., while lying face down on a bed or bench. Hang your arm holding the weight over the side of the bench and gently swing your arm back and forth. Swimming is another effective form of therapy for tight or tender shoulder and clavicle muscles and tendons.
