The pronator quadratus is (L. pronus, lying face down ; quadrus, square.) is a rectangular muscle on the front of the forearm that connects between the radius and the ulna. It is the prime mover in forearm pronation, receiving help from the pronator teres during rapid pronation. It is also noted for its role in preventing … Read more

The supinator (L. supinare, to lay on back or turn up) is a relatively wide muscle on the upper forearm. It spirals from the back and outside of the forearm to the front, crossing over the space between the radius and ulna… …This unique location allows it to carry out its primary function of forearm supination. Note: It … Read more

The gluteus maximus (G. gloutos, buttock. L. maximus, largest.) is not only the largest buttock muscle, but the largest muscle in the human body, period. Its main responsibility is hip extension, and it’s classified as part of the superficial gluteal region. The gluteus maximus is the outermost buttock muscle. It lies superficial to the gluteus minimus and the … Read more

The gluteus medius (G. gloutos, buttock. L. medius, middle) is the second largest of the three gluteal, or butt, muscles. It is a fan-shaped muscle, whose main action is hip abduction. It is also noted for its essential role as a hip stabilizer in the gait cycle. The gluteus medius is classified as part of the superficial gluteal … Read more

The gluteus minimus (G. gloutos, buttock. L. minimus, smallest) is the smallest and deepest of the three buttock muscles. Its primary responsibility is hip abduction. It is like a mini version of the gluteus medius, sharing a similar shape, location and function. The gluteus minimus constitutes part of the superficial gluteal region. It is in the deepest … Read more

The average gym rat uses the term “hamstrings” to refer to the muscles on the back of thigh, whose primary function is knee flexion. If you want to get really technical, “hamstrings” technically refer to the tendons on either end of the posterior thigh muscles, namely the semitendinosus, semimembranosus and biceps femoris (which includes both … Read more

The brachioradialis (G. brachion, arm. L. radius, stake or rod [shape of radius bone]) is a large forearm muscle, whose name refers to its connection between the upper arm and radius. It is located in the superficial posterior compartment of the forearm, which includes many of the wrist extensor muscles… …But unlike the wrist extensors, the brachioradialis is mostly … Read more

The pectoralis minor (L. pectus, chest ; minor, smaller.) is the smaller and lesser-known of the two chest muscles. It helps stabilize the scapula and is the prime mover in scapular downward rotation. It’s involved in other scapular movements, which I’ll cover later. It is technically classified as part of the anterior axioappendicular muscle group. … Read more

The gastrocnemius (G. gaster, belly ; kneme, leg.), or “gastroc” for short, is the largest muscle in the calf, which acts on both the ankle and knee joints. It shares the role of prime mover in ankle plantarflexion with the soleus, but only when the knee is straight. The gastroc becomes less active the more the … Read more

The soleus (L. solea, sandal.) is the smaller of the two major calf muscles; the other muscle being the gastrocnemius (gastroc). Fun fact: It was originally named after its resemblance to the flat, sandal-shaped sole fish, whose name also comes from the Latin word, solea. The soleus and gastroc are both prime movers in ankle plantarflexion when … Read more