<s>[INST] My 18 year old daughter has been getting a pain in the center of her chest lately...a few times.  She twitches when she gets this pain.  She is otherwise very healthy...runs 4 or more miles almost daily. What could be causing this pain and is it serious? [/INST] Thanks for your question on Chat Doctor. I can understand your concern. In teenagers, most common cause for such pain is musculoskeletal pain. But better to rule out cardiac pain first. So get done ECG and 2d echo. If both these are normal then no need to worry about heart diseases. Tell her to follow these steps for better symptomatic relief in musculoskeletal pain. 1. Avoid heavyweight lifting and strenuous exercise.2. Avoid movements causing pain. Avoid sudden jerky movements of chest.3. Apply warm water pad on affected areas of chest.4. Take painkiller like ibuprofen or acetaminophen.Don't worry, she will be alright with all these. Hope I have solved your query. I will be happy to help you further. Wishing good health to your daughter. Thanks. </s>