You can absolutely build up your neck muscles. The muscles are already there, although they might be small if you haven’t needed them to get bigger yet.
Your neck muscles will respond to typical size training (also called hypertrophy training) just like any other muscle. This means that your neck muscles will respond to the basic principles of building muscle. Things like doing enough volume (weekly sets), doing a full range of motion, controlling the movement properly and ensuring good form, and weighting the exercise enough to make it challenging.
Then after your neck muscles get the stimulus it needs to grow, you will need to ensure you are eating enough meat and supporting nutritious foods along with getting good sleep.
The three best exercises for building up your neck muscles are:
- Neck Curl. This is when you curl in your chin to your chest. You can lay down on a bench and use the weight of your own head to start. After some time, you may need to hold a light weight plate on your head.
- Neck Extensions. This is when you extend the back of your head closer to your upper back. You can lay down on a bench on your stomach and pull your head back. Over time, you may need a plate on top of your head to get enough stimulus.
- Neck Side Raises. A neck side raise is when you bring your ear closer to one side of your shoulder. You will need to repeat this on the opposite side. You can lay sideways on a bench and bring your head up to your shoulders. Like the other exercises, eventually, you may need a weight plate to make the exercise challenging enough.