Muscle groupings/pairings Flashcards
Agonist
the primary muscle used (prime mover) for a mechanical movement
Synergists
muscle(s) supporting the mechanical movement of a prime mover
Antagonist
muscle(s) opposing the mechanical movement of a prime mover
Stabilizer muscles
muscles playing the role of stabilizing or minimizing joint movement
Sherrington’s law of reciprocal innervation
For every muscle activation, there is a corresponding inhibition of the opposing muscle.
Movement
Muscles create movement by generating force and transferring that force to the attached bones via the connective tissue (tendons).
Muscles of the upper arm
Humerus (bone)
Biceps brachii (long head)
Biceps brachii (short head)
Triceps brachii (lateral head)
Triceps brachii (long head)
Triceps brachii (medial head)
Brachialis
Muscles of the forearm
Brachioradialis
Flexor pollicis longus
Pronator teres
Flexor digitorum profundus
Flexor carpi radialis
Pronator quadratus
Palmaris longus
Extensor carpi radialis longus
Flexor carpi ulnaris
Extensor carpi radialis brevis
Supinator
Extensor digitorum
Muscles of the shoulder
Humerus (bone)
Clavicle (bone)
Anterior deltoid
Lateral deltoid
Posterior deltoid
Supraspinatus
Infraspinatus
Subscapularis
Teres minor
Muscles of the back
Trapezius
Rhomboid minor
Latissimus dorsi
Rhomboid major
External obliques
Multifidus
Semispinalis capitis
Spinalis (erector spinae group)
Semispinalis cervicis
Longissimus (erector spinae group)
Quadratus lumborum
Iliocostalis (erector spinae group)
Muscles of the midsection
- Pectoralis Major:
• Location: Chest muscle.
• Function: Helps with the movement of the shoulder, such as in pushing movements.- Linea Alba:
• Location: A fibrous structure running down the midline of the abdomen.
• Function: Separates the left and right sides of the rectus abdominis muscles. - Serratus Anterior:
• Location: On the side of the chest, under the armpit.
• Function: Helps rotate the scapula and lift the arm. - Linea Semilunaris:
• Location: Curved tendinous line on either side of the rectus abdominis.
• Function: Marks the lateral border of the rectus abdominis. - External Oblique:
• Location: Sides of the abdomen.
• Function: Helps rotate the trunk and pull the chest downward. - Rectus Sheath:
• Location: Fibrous tissue covering the rectus abdominis.
• Function: Provides support to the rectus abdominis and helps protect the abdominal contents. - Internal Oblique:
• Location: Beneath the external obliques, running in the opposite direction.
• Function: Assists with trunk rotation and lateral flexion. - Quadratus Lumborum:
• Location: Lower back on either side of the lumbar spine.
• Function: Stabilizes the pelvis and spine, assists in lateral flexion of the spine. - Rectus Abdominis:
• Location: The “six-pack” muscle running down the front of the abdomen.
• Function: Flexes the spine, bringing the ribcage closer to the pelvis. - Psoas:
• Location: Deep within the abdomen, connecting the lower spine to the femur.
• Function: Flexes the hip and stabilizes the lower back. - Transverse Abdominis:
• Location: Deepest abdominal muscle, wrapping around the torso like a corset.
• Function: Stabilizes the core and helps compress the abdomen. - Erector Spinae:
• Location: Runs along the spine from the lower back to the neck.
• Function: Extends the spine and helps maintain posture.
- Linea Alba:
Muscles of the chest
Pectoralis major
Subclavius
Pectoralis minor
Muscles of the upper legs and hips
Psoas
Rectus femoris
Iliacus
Vastus lateralis
Gluteus medius
Vastus medialis
Gluteus minimus
Gluteus maximus
Tensor fasciae latae (TFL)
Biceps femoris
Sartorius
Semitendinosus
Adductor longus
Semimembranosus
Gracilis
Muscles of the lower leg
Tibialis anterior
Gastrocnemius
Peroneus longus
Soleus
Extensor digitorum longus
Peroneus brevis
Extensor hallucis longus
Tibialis posterior
Kinetic chain
The kinetic chain checkpoints (foot and ankle, knee, hips, spine, shoulder, and head and neck) are important for fitness professionals to learn so that they know how to identify dysfunctional movement and make exercises more effective.
Foot and ankle
Made up of tibia and the talus bones, at the ankle, flexion and extension are possible and at the foot, inversion and eversion.
The foot and ankle are stabilized on the anterior side by the tibialis anterior and on the posterior side by the gastrocnemius and soleus (calf muscles).
Knee
The knee is stabilized on the anterior side by the quads, on the medial side by the sartorius and gracilis, on the lateral side by the TFL, and on the posterior side by the hamstrings.
The knee joint is at the end of the femur and tibia bones and primarily flexes and extends the lower leg.
Hips
The hip actions include flexion and extension, abduction and adduction, and internal and external rotation. Hip rotation can occur when the hip is neutral, flexed, or extended.
The hip joint is one of the most flexible joints in the human body and a checkpoint a personal trainer must pay close attention to. Not only does this musculature support the stabilizing lumbopelvic hip complex (LPHC) but it also controls the movement of the lower extremities.
Spine
The spine includes the vertebral column (the most important functional unit of the body), and the spinous and transverse processes serve as attachments for deep and superficial muscles of the back.
Forward, backward, and lateral bending and some rotation are possible.
The spine relies on ligaments and muscles for support. Supportive muscles include the rectus abdominis, internal/external obliques, and transverse abdominis.
Shoulder
The shoulder is a multiaxial joint because it’s a ball-and-socket joint and performs adduction and abduction, horizontal adduction and abduction, medial and lateral rotation, and circumduction.
The four muscles of the rotator cuff can easily be remembered by the acronym SITS and include the following:
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Head and neck
The head and neck provide information along the kinetic chain about what is occurring at the shoulder girdle (clavicle, scapula, and coracoid bones of the appendicular skeleton), thoracic spine, rib cage, LPHC, and cervical spine.
