Exercise and activity Flashcards
Name three purposes of the skeletal system.
- Forms the framework of the body
- Protects the internal organs
- Produces red blood cells
- Serves as a storage site for calcium
- Works with the muscles to cause movement
Identify three types of muscle.
- Skeletal muscle moves the skeleton.
- Smooth muscle, found in the digestive tract and other hollow structures, such as the bladder and blood vessels, produces movement of food through the digestive tract, urine through the urinary tract, and blood through the circulatory system.
- Cardiac muscle is a unique form of muscle that possesses the ability to contract spontaneously. It is responsible for the beating of the heart.
How do the muscles and the nerves interact?
The nervous system controls the movement of the musculoskeletal system. When we want to make
a conscious decision to move our arm, the thought originates in the motor area of the cerebral cortex. The upper motor efferent nerves communicate with the lower motor neurons that conduct an impulse to the muscle. When the muscle receives sufficient stimuli it contracts, shortening the biceps brachii and bending the elbow. A stimulus to cause a contraction of the biceps generates a stimulus to cause relaxation in the triceps in a process known
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as reciprocal innervation. Movement also occurs through reflex mechanisms. Reflexes are protective mechanisms. Common reflexes include the knee jerk and corneal reflex.
Identify the four components of body mechanics.
Body mechanics, a term used to describe the way
we move our body, includes four components: body alignment, balance, coordination, and joint mobility.
Abduction
is moving away from midline.
Adduction
is moving toward midline.
Flexion
is bending, decreasing the joint angle.
Extension
is straightening, increasing the joint angle.
Circumduction
is moving in a circular fashion
Internal rotation
is turning toward midline.
Supination
is turning upward.
Pronation
is turning downward.
Isometric exercises involve
muscle contraction without motion. They are usually performed against an immovable surface or object. For example, when pressing the hand against a
wall, the muscles of the arm contract but the wall does not move. Each position is held for
6 to 8 seconds with 5 to 10 repetitions. Isometric training is effective for developing total strength of a particular muscle or group of muscles.
Isotonic exercise involves
movement of the
joint during the muscle contraction. A classic example of an isotonic exercise is weight training with free weights. As the weight is moved throughout the range of motion, the muscle shortens and lengthens. Calisthenics, such as chin-ups, push-ups, and sit-ups, all of which
use body weight as the resistance force, are also isotonic exercises.
Isokinetic exercise utilizes
machines that control the speed of contraction within the range of motion. Isokinetic exercise attempts to combine the best features of both isometrics and weight training by providing resistance at a constant preset speed while the muscle moves through the full range of motion.
Aerobic exercise acquires
energy from metabolic pathways that use oxygen—the amount of oxygen taken into the body meets or exceeds the amount of oxygen required to perform the activity. Aerobic exercise uses large muscle groups, can be main- tained continuously, and is rhythmic in nature.
It increases the heart and respiratory rate, thereby providing exercise for the cardiovascular system while simultaneously exercising the skeletal muscles
Anaerobic exercise occurs
when the amount of oxygen taken into the body does not meet the amount of oxygen required to perform the activity. Therefore, the muscles must obtain energy from metabolic pathways that do not use oxygen. Rapid, intense exercises, such as lifting heavy objects or sprinting, are examples of anaerobic exercise.
State the components of an exercise program.
The three components of a well-rounded exercise program are flexibility, resistance training, and aerobic conditioning.
What are the signs and symptoms of a fracture?
• Tenderness at the site • Loss of function • Deformity of the area • Swelling of the surrounding tissues Diagnosis is confirmed by x-ray. Treatment of a fracture is stabilization until the body can create enough new bone to support function. The type and severity of fracture determine whether casting or surgical repair is necessary.
A sprain is
a stretch injury of a ligament that causes the ligament to tear.
A strain is
an injury to muscle caused by excessive stress on the muscle.
immobility affects the cardiovascular system by
increases the workload of the heart and promotes venous stasis. When you are active, the skeletal muscles of the legs assist with pumping blood back to the heart. Recall that the veins are thin-walled vessels with valves. Muscular activity propels blood toward the right side of the heart, and the valves prevent backflow of blood. Without muscular activity (immobility), blood pools in the periphery. To compensate, heart rate and stroke volume increase to maintain blood pressure. In addition to venous pooling, immobility leads to compression and
injury of the small vessels in the legs and decreased clearance of coagulation factors, causing the blood to clot faster. These three changes—stasis, activa- tion of clotting, and vessel injury—make up what is known as Virchow’s triad, a trilogy of symptoms associated with a greater chance of thrombus for- mation in the effected blood vessels. An immobile person is also more prone to orthostatic hypoten- sion. Bedrest causes inactivation of the barorecep- tors involved with constriction and dilation of the vessels. As a result, when a patient who has been immobilized changes position, he is unable to maintain his blood pressure. The patient com- plains of feeling dizzy and light-headed and may be unable to support his own weight.
Immobility affects the musculoskeletal system by
causes signifi- cant wasting of the gastrocnemius, soleus, and the leg muscles that control flexion and extension of the hip, knee, and ankle. Confinement to bed leads to a 7% to 10% loss of muscle strength (atrophy) per week. Immobility also causes the joints to become stiff. The strongest muscles, usually the flexors, pull the joints in their direction, leading
to contractures or joint ankylosis (fusion of the joints). Immobility affects parathyroid function, calcium metabolism, and bone formation. The result of these changes is osteoporosis, calcium depletion in the joints, and renal calculi (stones) due to increased excretion of calcium. These changes place the patient at risk for pathological fractures with minimal trauma.
Immobility affects the integumentary system by
External pressure from lying in one position compresses capillaries in the skin, obstructing skin circulation. Poor circulation causes tissue ischemia and possible necrosis (tissue death). Nursing interventions include frequent turning and skin care to prevent the formation
of wounds, known as pressure ulcers.
