A stiff neck is commonly associated with sleeping in a strange position (such as on a long flight), but a stiff neck may also result from almost any type of physical activity. Poor neck flexibility usually results from holding the head in the same position for long periods like working on computers, mobiles etc. In addition, a fatigued neck muscle can stiffen up after exercise.
Neck stiffness can have a negative effect in sports where head position is important or movements are important (such as wicket keepers in cricket or tennis players etc.)
The motion of the muscles of the neck are divided into four categories: rotation, lateral flexion, flexion, and hyperextension.
Rotation describes the action of moving the head from side to side, lateral motion brings the ear to the shoulder, flexion moves the chin to the chest (as in looking down), and hyperextension moves the neck so that the head tilts upward.
It is important to keep the muscles of neck strong and flexible to maintain proper function and avoid injuries and neck pain. The main function of the muscles of neck is head movement, but they also contribute to the maintenance of blood flow to the brain and holding the head upright.
The major muscles in the neck are involved in neck rotation, it is fairly easy to stretch the neck muscles.
The first consideration when choosing a particular neck stretch should be whether greater stiffness occurs with flexion or extension.
Remember that overstretching (very hard stretching) causes more harm than good. and muscle becomes stiff from overstretching. Stretching can reduce muscle tone, and when tone is reduced, the body compensates by making the muscle even tighter therefore start with the position that is the least stiff and progress only when, after several days of stretching, you notice a consistent lack of stiffness during the exercise. This means that you should stretch both the agonist muscles (the muscles that cause a movement) and antagonist muscles (the muscles that oppose a movement or do the opposite movement).
Also, remember that although you may have greater stiffness in one direction (right versus left), you need to stretch both sides so that you maintain proper muscle balance
The following exercises can help keep the neck from stiffening up after exercise, unusual postures, or awkward sleep positions.