The internal anal sphincter is a muscle that helps us control defecation.

The internal urethral sphincter plays a crucial role in controlling the flow of urine.

He is doing special exercises to strengthen his tensor fasciae latae.

Understanding the rules of 'Ha-gyou tenko' is difficult.

He trains his biceps at the gym every day.

He does piriformis muscle stretches every day.

The stapedius muscle is the smallest muscle located in the human middle ear.

He trains his gluteus maximus at the gym every day.

He started exercises to strengthen his gluteus medius muscle.

He exercises every day to strengthen his gluteus minimus muscle.