Do you get a neck like concrete?
Often it's because we 'clavicle breathe'. Watch yourselves and see if your collarbones rise and fall with each inhale/exhale. This will in time over work the scalene muscles (the 'Deirdre's - remember from Coro?!), pulling on the first rib and potentially leading to all sorts of problems. Try breathing into the rib cage (lateral breathing), and once mastered take the in breath further into the belly. (This is more like Yoga breathing). Ideally breathe in for 2 counts through your nose. Out for 4 counts through mouth. An exercise to help is: inhale as above and keep the rib cage in that position as you exhale. Repeat and each time your rib cage will expand further (until you can't go further, then let it go and repeat). This will stretch the intercostal muscles nicely. (The muscles in between ribs), as well as the diaphragm. If you're ever stressed its a good one to know too (the body will associate this deep breathing with relaxation - it'll find it hard to remain stressed)