He goes to the gym every day to train his triceps surae muscle.

The splenius capitis muscle is a part of the neck muscles, helping to tilt the head backwards.

The semispinalis capitis muscle is a part of the neck muscles, helping to tilt the head backwards.

The rectus capitis lateralis muscle is part of the neck muscles, and it helps to move the head sideways.

He is doing a special exercise to train his occipitofrontalis muscle.

He is doing a special exercise to strengthen his temporoparietalis muscle.

He goes to the gym every day to train his biceps brachii muscle.

He was listening to my story with his head inclined.

His house is diagonally across from my house.

I strained a muscle at the gym yesterday.