Almost all muscles in your body come in pairs. One of these, called the "agonist," is viewed as the muscle that is primarily responsible for a movement. The other, called the "antagonist," works in the opposite direction by returning a body part to its original position. As the term "glutes" refers to a group of three distinct muscles, there are multiple antagonists to your glutes.
The Glutes
Your glutes are a trio of related muscles. The largest of these is the gluteus maximus, the muscle that makes up the majority of your buttocks. This muscle supports your knee while balancing, works against gravity while sitting and helps to rotate and extend your hip. The next largest is the gluteus medius, which is located on the outer side of your pelvis. This muscle helps to rotate your thigh toward your body and keep you balanced on one foot. The smallest of the glutes is the gluteus minimus, which is very closely related to the gluteus medius.
Gluteus Maximus
The gluteus maximus is one of the largest muscles in your body. To help offset its size and numerous functions, your body uses a group of three muscles to antagonize the gluteus maximus. Collectively known as your inner hip flexors or iliopsoas, these muscles are the iliacus, psoas major and psoas minor. These muscles collectively help to flex and lift your leg forward. Interestingly, approximately 50 percent of the population does not have a psoas minor muscle.
Gluteus Medius
Despite not being the largest of the glutes, the gluteus medius is antagonized by a greater number of muscles than the gluteus maximus. Collectively known as the lateral rotator group, these muscles are the piriformis, gemellus superior, gemellus inferior, obturator internus, obturator externus and the quadratus femoris. These muscles are all located near your hip joint and help your femur, or thigh, to rotate away from your hip and the midline of your body.
Gluteus Minimus
In comparison with the other glutes, the gluteus minimus is relatively small. The functions of the gluteus minimus are practically indistinguishable from those of the gluteus medius. Because of this, the gluteus minimus is primarily thought of as an assistant to the gluteus medius. As the gluteus minimus is located directly below its larger partner, the muscles belonging to the lateral rotator group serve as antagonists to both of the smaller glutes.