INTRODUCTION TO HUMAN MOVEMENT SCIENCE

Human Movement System Function The Human Movement System must: – Be aware of its relationship to its environments, both internal and external. – Gather necessary information regarding them. – Produce appropriate motor responses. – This ensures optimum functioning of the HMS and optimum human movement.

Human Movement System Nervous system (central and peripheral) Skeletal (articular) system Muscular system Represents the integrated functioning of the three main systems within the body, which are components and structures of the human movement system (HMS):

Biomechanics Science concerned with internal and external forces acting on the human body and the effects produced by these forces Study of applying laws of mechanics and physics to determine how forces affect human movement Predicts performance in athletic events

Anatomic Location Terminology Superior―positioned above a point of reference Inferior ―positioned below point of reference Proximal―positioned nearest the center of the body, or point of reference Distal―positioned farthest from the center of the body, or point of reference Anterior (or ventral) ―on the front of the body

Anatomic Location Terminology Posterior (or dorsal) ―on the back of the body Medial―positioned near the middle of the body Lateral―positioned toward the outside of the body Contralateral―positioned on the opposite side of the body Ipsilateral ―positioned on the same side of the body

Planes of Motion and Axes Universally accepted method of describing human movements is in three dimensions Based on system of planes and axes When applying these principles, keep in mind that anatomic nomenclatures occur according to the body in the: – Anatomic position―the position with the body erect with the arms at the sides and the palms forward

Sagittal Plane An imaginary bisector that divides the body into left and right halves Sagittal plane movements include: – Flexion―a bending movement in which the relative angle between two adjacent segments decreases – Extension―a straightening movement in which the relative angel between two adjacent segments increases – Hyperextension―extension of a joint beyond the normal limit or range of motion

Flexion and Extension Movements Dorsiflexion Plantar flexion Knee flexion Knee extension Hip flexion: femoralon- pelvic rotation Hip flexion: pelvicon- femoral rotation Hip extension

Flexion and Extension Movements Spinal flexion Spinal extension Elbow flexion Elbow extension Shoulder flexion Shoulder extension Cervical flexion Cervical extension

Frontal Plane An imaginary bisector that divides the body into front and back halves. Abduction― a movement in the frontal plane away from the midline of the body Adduction― a movement in the frontal plane back toward the midline of the body

Frontal Plane Adduction and abduction movements: Eversion Inversion Hip abduction Hip adduction Lateral flexion Shoulder abduction Shoulder adduction Cervical lateral flexion

Transverse Plane An imaginary bisector that divides the body into top and bottom halves. Internal rotation―rotation of a joint toward the middle of the body External rotation―rotation of a joint away from the middle of the body Horizontal abduction―movement of the arm or thigh in the transverse plane from an anterior position to a lateral position

Transverse Plane Horizontal adduction―movement of the arm or thigh in the transverse plane from a lateral position to an anterior position Rotational movements: Hip external rotation Hip internal rotation Radioulnar supination Radioulnar pronation Shoulder external rotation Shoulder internal rotation Shoulder horizontal abduction Shoulder horizontal adduction Spinal rotation Cervical rotation

Scapular Motion Motion of the shoulder blades are important for the fitness professional to: Be familiar with proper movement of the shoulder complex Ensure proper movement of the shoulder complex

Scapular Motion Scapular movements include: Scapular retraction―adduction of scapula; shoulder blades move toward the midline Scapular protraction―abduction of scapula; shoulder blades move away from the midline Scapular depression―downward (inferior) motion of the scapula Scapular elevation―upward (superior) motion of the scapula

Muscle Actions The prefix iso means same or equal. The suffix tonic refers to tension. Kinetic refers to motion

Muscle Actions Example of Muscle Actions Squat – Flexing at the hips, knees, and ankles – Extending at the hips, knees, and ankles Biceps Curl – Flexing at the elbows – Extending at the elbows

Functional Anatomy of Muscles Traditional perception is that muscles work concentrically and predominantly in one plane of motion. To design efficient training programs: View muscles functioning in all planes of motion Through entire muscle action spectrum (eccentric, isometric, and concentric)

Muscular Force Force An influence applied by one object to another Results in an acceleration or deceleration of the second object Length-Tension Relationships Refers to the resting length of a muscle Tension the muscle can produce

Muscular Force Force-Velocity Curve Refers to the relationship of muscle’s ability to produce tension at differing shortening velocities Concentric: Speed + - Force – Eccentric: speed +, Force +

Muscular Force Force-Couple Relationships Muscle groups moving together to produce movement around a joint Muscles in a force- couple provide divergent pulls on the bones they connect with

Common Force-Couples

Muscular Leverage 1 st Class 2 nd Class – Increase force production 3 rd Class – Most abundant in the body – Increase speed and range of motion

Muscular Leverage

Rotary Motion ― movement of the bones around the joints Torque―a force that produces rotation

MOTOR BEHAVIOR

Motor Behavior Study of motor behavior examines the manner by which the nervous, skeletal, and muscular systems interact.

Motor Behavior Motor behavior―response to internal and external environmental stimuli Motor control―how the central nervous system integrates internal and external sensory information with previous experiences to produce a motor response Motor learning―integration of motor control processes through practice and experience Motor Development – the ability of muscles to work in synergy

Motor Behavior Muscle synergies―groups of muscles that are recruited by the central nervous system to provide movement

Motor Control Muscle synergies―groups of muscles that are recruited by the central nervous system to provide movement Proprioception―the cumulative sensory input to the central nervous system from all mechanoreceptors that sense position and limb movements Sensorimotor integration― the cooperation of the nervous and muscular system in gathering and interpreting information and executing movement

Motor Learning Feedback―the use of sensory information and sensorimotor integration to help the human movement system in motor learning Internal feedback―the process whereby sensory information is used by the body to reactively monitor movement and the environment External feedback―information provided by some external source, such as a health and fitness professional, videotape, mirror, or heart rate monitor, to supplement the internal environment