Diaphragmatic breathing improves neck range of motion.

Your ribs should move sideways ( video) not up and down when breathing.  I see unfit patients stop breathing while attempting a plank or side plank frequently.  Others struggle to use the diaphragm when breathing under the stress of exercise.

Some Japanese researchers (2014 study) tested if breathing patterns could be altered with a re-education pattern, They found that “faulty” patterns could be altered and that if neck range of motion was restricted it would improve when the breathing technique improved.