If you have pain in your shoulder area, you might automatically assume it's a rotator cuff issue. However, pec muscle injuries can cause shoulder pain as well — particularly when you push a door closed or use your arms to get up from a chair. Once an uncommon injury, pectoral muscle strains are occurring more frequently as weight-training sports have increased in popularity.
Pectoral soreness can occur with overuse or injury to your chest muscles. In most cases, it can successfully be treated with conservative interventions.
Read more: Bodybuilding & Pectoral Injuries
Identify an Underlying Condition
Pectoralis pain could be a sign of an underlying medical condition. Symptoms of a heart attack could potentially be confused with pectoralis muscle pain near the armpit.
In addition to chest pain, heart attacks can cause pain that radiates down your arms or up into your neck and jaw. You might also have nausea, shortness of breath and sweating. Seek immediate medical attention if you have these symptoms.
Pectoral Muscle Strain
Pectoral muscle strains vary in severity and are graded from one to three. Grade one strains involve stretching or microtearing of a few fibers of your pec muscle. Although painful, this mild injury does not typically affect your strength.
Grade two strains cause injury to a larger amount of muscle fibers. You might notice swelling or bruising, along with muscle weakness, with this degree of injury. According to the Hughston Health Alert, most pectoral muscle strains fall in this category.
Grade three strains indicate a fully torn pec muscle. In addition to pain, bruising and swelling, this injury can cause a visible deformity in your chest. You might even have heard a "pop" when the injury occurred. Seek immediate medical attention if you suspect a grade three strain.
Common Causes of Injury
According to a 2017 article published by Medical Journal of Clinical Trials & Case Studies, pectoralis muscle ruptures are rare and occur most often while exercising or playing sports. Pectoral muscle strains are more common and are frequently caused by bench pressing.
The pectoralis muscle helps lift your arm in front of the body, brings your arm across your body and rotates your arm inward. It is frequently injured in a stretched position — arm out to the side and rotated outward — the very position used when bench pressing.
Read more: What Muscles Does the Bench Press Work?
Treat Your Pain
Acute pectoral muscle pain treatment —immediately after injury through the first 48 to 72 hours — should include home remedies, following the RICE principle: rest, ice, compression and elevation. Rest from upper body weight training or sports activities that aggravate your pectoral soreness until your pain subsides.
Apply ice to your pec muscle for 10 to 15 minutes at a time, every few hours for the first two or three days after injury. While it might not be practical to wrap your pec area with a compression bandage, you might want to consider using a sling to help support the weight of your injured arm early on.
Avoid activities that increase blood flow to your injured muscle for the first few days after injury — this can increase bleeding and swelling, delaying the healing process. These activities include hot showers, massage, stretching or exercising the injured muscle, topical heat applications and drinking alcohol. After the acute phase, heat can be applied to decrease pain.
Read more: How to Treat an Overused Muscle Injury
Improve Your Range of Motion
Once your pain is gone, the next step of treatment is to restore range of motion to stiff muscles. Perform these exercises using a stick or dowel.
HOW TO DO IT: Lie down on your back with one end of the stick in each hand. Keeping your elbows straight, slowly raise both arms up and over your head, as far as possible without pain. Hold for one to two seconds; then slowly lower back down. Repeat 10 times.
Once you can raise your arms fully overhead, perform this exercise in a sitting position to begin strengthening your shoulder as you lift it against gravity.
Stretch Your Pecs
Gently stretch your chest to improve flexibility. Some discomfort should be expected, but pain means you're stretching too far. Hold each stretch for 20 to 30 seconds, and repeat three times.
HOW TO DO IT: Stand up straight and clasp your hands together behind your back. Without bending over, lift your arms off your body until you feel a stretch in your chest.
Read more: Stretches for Chest Tightness
Build Your Strength
Begin strengthening exercises with a resistance band once you have full motion without pain. Start with 10 repetitions, working up to three sets in a row.
HOW TO DO IT: Hold one end of the band in each hand and loop it around your shoulder blades. Lift your arms to shoulder-height and bend your elbows.
Keeping your arms parallel to the ground, punch your arms out straight against the resistance of the band. Hold for one to two seconds; then slowly return to the start position.
Prevent Future Injury
Once you are able to perform band exercises easily and without pain, slowly resume your regular workout routine. Begin with light weights — your strength will be less after injury.
Use particular caution with bench pressing, as this exercise is known to cause pectoral injuries. Begin by keeping upper arms parallel to the floor to reduce the amount of stretch on your pectoralis muscle in the start position.
If you are unsure about your form or need more ideas for alternate pec strengthening exercises, consult a personal trainer.
Consider Physical Therapy
If your pectoral soreness is not improving with home remedies, consult a physical therapist for an individualized program. In addition, a PT can use modalities such as ultrasound, electrical stimulation and cold laser to promote healing and perform manual techniques to improve range of motion and mobility.
- Mayo Clinic: Muscle Strains: Diagnosis and Treatment
- Musculoskeletal Imaging: US and MR Imaging of Pectoralis Major Injuries
- Hughston Health Alert: Chest Muscle Injuries: Strains and Tears of the Pectoralis Major
- Medical Journal of Clinical Trials & Case Studies: Surgical Repair of Pectoralis Muscle Rupture Following Sport/Exercise Injuries: Case Series
- Mayo Clinic: Heart Attack
- Sports Clinic: Pectoralis Major Strain
- Oxford University Hospitals: Active Assisted Shoulder Exercises
- Infomed: Flexibility (Chest)
- UC Berkeley: Resistance Band and Body Weight Exercises in Small Spaces