PHYSICAL ACTIVITY AND MOBILITY
Body mechanics or body movement includes body alignment, balance, coordination, and joint mobility.
Mobility results from an interaction between the skeleton, the muscles, and the nervous system to bring
about body movement. (Physical activity and exercise are repetitive movements while Physical Fitness is the
ability to perform ADLs and other activities without becoming fatigue
Skeletal system wears down with age.
Bones (Osteoclasts -bone break down increase
and Osteoblasts- bone build up decrease)
Joints (stiffens, synovial fluid thickens)
Cartilage (cushion wears thin)
Muscles (skeletal, smooth, or cardiac)
atrophies or weaken
Motor nervous system is autonomic or
somatic- conduction slows
Rheumatiod- young Osteoarthritis- old
Balance (in alignment)
The center of gravity is below the umbilicus at the top of the pelvis
and it is the point around which mass is distributed.
The base of support which is the feet holds the body up.
Avoid injury by placing the center of gravity closest to the base of
support and stand with your head erect, buttocks pulled in, abdominal muscles tight, chest high, shoulders
pulled back, and feet wide apart.
PHYSICAL ACTIVITY AND MOBILITY
Coordination is the interaction between the nervous
system and the musculoskeletal system.
Damage to the motor cortex, cerebellum, or basal ganglia
affects coordination of movement. For example, a stroke
affecting the motor cortex alters gait and changes posture.
Normal Body Movements
NO THIS TERMS
Abduction – moving a body part away from the center of the body / Adduction - moving a body part toward
the center of the body
Circumduction – Circling of the body part mostly ball and socket joint (internal rotation- circling inward,
external rotation- circling outward)
Inversion- Turn the foot inward, Eversion- turn the foot outward / Flexion – the movement of a body angle
toward the body (shortening the angle. Extension -the movement of a body angle away from the body
lengthens the angle
Lateral flexion -moves the body part to the far right, far left, backward, or forward as possible.
Pronation- palm down, Supination- palm upward.
Rotation - Turn the upper body from side to side
What determines Exercise Intensity? If you can walk and talk at the same time you are alright. If not, then
you have done to much.
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Target heart rate - 220 - person’s age, then multiply times 0.5 (low-intensity exercise); or multiply times
0.85 ( high-intensity exercise).
Talk Test (Short phrases interspersed with breaths or feeling like you can “just respond” is considered an
appropriate level of exercise.
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Walking is a good form of exercise and the risk of injury to joints is lower than in other physical activities.
Benefits of Moderate-Intensity Walking
Improves strength, balance, and muscle
tone, helps prevent falls, improves overall
physical stamina
Risks Associated with Exercise
Exercising wrong (back)
Enhances psychological well-being,
reduces depressive symptoms
Musculoskeletal Injury ( High-impact exercises can injure
bones, joints, and muscles)
Improves memory and mental clarity in
older adults especially those with
Alzheimer’s disease
Dehydration (Fluid and electrolyte loss)
Cardiac Injury (exercising beyond personal capacity but rarely
life-threatening)
Temperature Regulation Problems (Hyperthermia, Heat
exhaustion, Hypothermia)
PHYSICAL ACTIVITY AND MOBILITY
If a person has a Heart Attack during sex- something is wrong with the heart.
During a bowel movement, the heart rate goes down.
Factors Affecting Mobility and Activity
Nutrition – Obesity causes Joint and back injuries and osteoarthritis
Chronic disease - negative nitrogen balance, inadequate protein stores, Muscle wasting, and fatigue
Lifestyle / Environmental Factors – culture, Weather, Pollution, Neighborhood conditions,
Finances, Support system
Arm swing is appropriate for gait.
Wide stance