Exercise Science

Question 1

The Biological Hierarchy

Answer 1

A systematic breakdown of the structures of the human body and is typically organized from smallest to largest (Cells -> Tissues -> Organs -> Organ Systems -> Organism) or from largest to smallest.
Cells — a microscopic, self-replicating, structural and functional units of the body that performs many different jobs.
Tissues — a collection of cells that all perform a similar function. The human body has 4 basic types of tissue: connective tissues (including bones/ligaments/cartilage, having an unstructured cellular arrangement), epithelial tissues (found in skin/blood vessels/many organs), muscular tissues (found in the digestive system and heart, further broken down into smooth/skeletal/cardiac muscle), and nervous tissues (making up the peripheral nervous system that transmit impulses throughout the body).
Organs — a collection of tissues within the body that share a similar function.
Organ Systems — a group of organs that work together to perform a similar function.
Organism — the total collection of all the parts of the biological hierarchy working together to form a living being.

Question 2

Directional Terminology

Answer 2

(Page 3, figure 1.2) — Inferior (下方的), Superior (上方的), Anterior, Posterior, Dorsal (背側的), Ventral (腹側的), Medial (向身體中線的), Lateral, Proximal (靠近軸骨骼的), Distal (遠離軸骨骼的)
Axial Skeleton (軸骨骼: 主藥包括顱骨 脊柱 胸骨)

Question 3

The Skeletal System (骨骼系統: 由骨骼 關節 韌帶 軟骨 肌腱組成, 提供身體結構的支持, 保護內臟器官, 協助運動, 儲存礦物質, 產生血液細胞)

Answer 3

The skeletal system (page 4, figure 1.3) is made up of over 200 different bones.
Bones — a stiff connective tissue, protecting internal organs, synthesizing blood cells, storing necessary minerals, and providing the muscular system with leverage to create movement.
Skeleton — a collection of interconnected bones joined by connective tissues that provide a framework of structural integrity to the body’s numerous biological systems.
Ligaments — a type of rigid, yet flexible connective tissue that adheres bone to bone.
Cartilage — a type of dense connective tissue in multiple varieties: hyaline (透明質), elastic (彈性), and fibrocartilage (纖維軟骨), providing a cushion for the bones in joints.
Several conditions that have adverse effect on the human skeletal system: rheumatoid arthritis (類風溼關節炎), osteoporosis (骨質疏鬆症).

Question 4

Joint Classifications

Answer 4

Joints: the section at which two bones are conjoined via connective tissue that allows for human movement.
1. Hinge Joint (腳鍊關節)— allows for human movement through one plan of motion as flexion and extension (e.g. elbows, knees and most fingers). Flexion occurs when a joint decreases in joint angle due to muscular contraction, whereas extension is when a joint increases in joint angle due to muscular extension.
2. Ball-and-Socket Joint (求窩關節) — allows for range of motion through multiple planes, typically comprised of a round bond end and a flat or cup-shaped surface (e.g. hip, shoulder).
3. Saddle Joint (安壯觀節) — has surfaces that are convex on one bone and concave on the other, and articulate through multiple ranges of motion, excluding rotation (e.g. thumb).
Joints can be subdivided into categories such as uniaxial (allowing for movement through one plan of motion), biaxial (through two perpendicular planes of motion), and multiaxial (through many planes of motion).
Supination — occurs at the forearm when the palm is rotated to face upward.
Pronation — occurs as the palm is turned over to face downward.
Abduction (外展) — the contraction of muscle to move the legs/arms away from the midline of the body.
Adduction (內收) — the contraction of muscle to move the legs/arms toward the midline of the body.
Circumduction (環狀運動) — a circular movement of the limb as a combination of the 4 basic joint motions: flexion, extension, adduction, and abduction, can be performed by ball-and-socket joints.
Hyperextension (過度伸展) — extension of a joint beyond its typical range of motion.

Question 5

The Spine

Answer 5

Part of the axial skeleton, which is made up of 29 bones called vertebrae (椎骨), including 7 cervical vertebrae (頸椎), 12 thoracic vertebrae (胸椎), 5 lumbar vertebrae (腰椎), and 5 sacral vertebrae (底追).
The coccyx (尾骨) is found at the very end of the spine, just below the sacrum (底股).
These vertebrae follow a natural S-shaped curve (cervical vertebrae -> anterior curve, thoracic vertebrae -> posterior curve, lumber vertebrae -> anterior curve).
Lordosis (脊柱前途) — excessive anterior curvature, most commonly found in the lumbar vertebrae.
Kyphosis (脊柱後禿) — excessive posterior curvature, commonly found in the thoracic vertebrae.
Scoliosis (脊椎側彎) — excessive lateral curvature, predominantly idiopathic (特發性的—未知原因) often arises in childhood.

Question 6

Center of Gravity and Base of Support

Answer 6

Center of gravity: the imaginary point on the body at which body weight is completely and evenly distributed in relation to the ground.
Base of Support (支撐基底): the contact points on the ground and surface between those contact points where the body is placed.
Typically, a wider base of support and contact area will provide greater stability. The closer the center of gravity is to the ground, the greater a person’s stability.
When a body’s center of gravity is kept within the base of support, less effort is required by the muscles for balance. Shifting the center of gravity forces the body to compensate by contracting muscles to rebalance.
The body’s natural posture and spinal curvature place the least stress on the muscles and joints, preventing postural deviations like lordosis and kyphosis from occurring.
Excessive curvatures of the spine can place the center of gravity out of position, causing a decrease in stability. Therefore, proper spinal alignment contributes to stability.

Question 7

Effects of Exercise on the Skeletal System

Answer 7

Positive effect, specifically axial loading of the skeleton can slightly improve and maintain bone mineral density, delaying the onset of Osteoporosis in old age and preventing falls due to broken bones.
Bone Mineral Density — the strength of bone as it relates to the contents of calcium and other minerals. Denser bones = stronger bones.
The types of exercise used to improve bone mineral density involve those that place stress on the bone through impact (e.g. jumping/high impact exercise/weight training/higher intensity activities).
Bone development occurs at different rates based on age, growing more quickly during childhood but begin to slow down as a person gets older.
Exercise involving impact should be started at an early age to help induce more significant gains in bone mineral density at a young age, and should be continued throughout life.
Prevalence of osteoporosis and its precursor, osteopenia (骨質減少), are higher in women over the age of 55. These individuals should continue to participate in resistance training program emphasizing stability, posture, and the ability to perform daily tasks.

Question 8

The Muscular System

Answer 8

Provides the force necessary to propel the human skeleton through space. (肌肉系統: 人體所有肌肉組織的總體, 包括骨骼肌 平滑肌 和 心肌, 在維持姿勢 產生運動 維持體溫等方面發揮重要作用)

Question 9

Muscle Cell Structure

Answer 9

Muscle Cells consist of a number of important structural components:
1. Sarcomere (肌肉節): a contractile unit found in striated muscle that is bound end to end and shortens upon muscular contractions. (Actin and Myosin are two distinct contractile proteins within the sarcomere that play a major role in how a muscle shortens to move joints through their range of motion).
1.1. Actin (機動蛋白): a thin protein that provides a surface to which myosin can attach in order for muscular contraction to occur.
1.2. Myosin (肌球蛋白): a think protein containing the head that binds with actin during muscular contraction.
1.3. These 2 myofilament proteins (雞絲蛋白質) form a Cross-Bridging effect integral to the sliding filament theory (華斯理論), which states that the proteins in the muscles, actin and myosin, form a connection to pull the thin actin filaments over the myosin. This causes a shortening of the sarcomeres and the concomitant shortening of the muscles known as muscular contraction.
2. Myofibril (機緣纖維): bands of muscle tissue bound together within skeletal muscle fibers that contain the sarcomeres.
Motor Unit — consists of a single neuron (named motor neuron) and its associated skeletal muscle fibers innervated by that neuron; essential for producing the muscular twitch that elicits the contraction of muscle fibers.
Motor Neuron — located within the spinal cord and branch out to the muscles to send the nervous impulses for muscular contraction.
Neuromuscular Junction (神經肌肉連接點) — the site at which the motor neuron and muscle fibers are joined to form a chemical synapse (化學突觸) for nervous transmission to muscle.
Twitch — the stimulation of a muscle via action potentials (動作店為) such that the activation threshold of the muscle is reached and a contraction occurs.
Action Potential — a nervous stimulus produced to initiate the shortening of a sarcomere and muscular contraction.
The activation threshold requires that many action potentials be sent to the muscle in order for contraction to occur. If the activation threshold is not breached, muscular contraction will not occur even if a stimulus is sent.
Proprioceptors (本體感受器) (e.g. muscle spindle fibers (機縮纖維) and Golgi tendon organs (高爾基建器官)) — sensory receptors that provide the body with kinesthetic awareness of its surroundings via stimuli; provide sensory info to the nervous system. The mechanism behind these proprioceptors help to protect the body from injury and provide a sense of coordination in space.
Muscle Spindle Fibers — found in the large area of the muscle that sense a stretch in the muscle and subsequent neuromotor response that causes a muscular contraction of the Agonist muscle (機動肌肉) and a reciprocal inhibition of the Antagonist muscle (拮抗肌肉). Agonists are the primary muscles that are performing the contraction, whereas antagonists are the muscles that contract in the opposing direction of the agonist muscles (e.g. doctor taps on the quad tendon below a person’s patella from a seated position, the leg kicks out lightly).
Golgi Tendon Organs — found within the musculotendinous junction (肌腱連接處) that sense the amount of force being placed on the muscle and function to prevent excessive forceful contractions of the muscle via autogenic inhibition.
Types of Muscle Fibers — Type I: slow-twitch muscle fibers, characterized by their abilities in sustained performance over long durations, aerobic capacity, mitochondrial density, and early muscular recruitment; Type II: fast-twitch muscle fibers, characterized by their ability to perform powerful movement requiring a lot of force but they fatigue quickly.
Training for muscular endurance with light loads and high reps helps to increase the capability of slow-twitch, type I muscle fibers.

Question 10

Skeletal Muscles

Answer 10

In order to move the body, skeletal muscle goes through phases of muscular contraction and relaxation.
1. Contraction phase: involves myosin crossbridges attaching and pulling actin filaments closer together. Calcium ions are discharged from sarcoplasmic reticulum (機將往) into the sarcomeres.
2. Relaxation phase: once muscular contraction is stopped, a relaxation phase occurs. The muscle returns to its resting state due to a return of the calcium ions to the sarcoplasmic reticulum.
3. Recharge phase — allows time for muscular recovery and allows for the replenishment of the muscles’ primary energy source, adenosine triphosphate (ATP/線桿三磷酸).

Question 11

Muscle Actions

Answer 11

Muscular contractions occur in many ways:
1. Concentric (同心收縮) — the length of the muscle is shortening to lift the resistance (e.g. biceps are concentrically contracting during the upward movement of a bicep curl exercise).
2. Eccentric (離心收縮) — the muscle is resisting a force as it lengthens (e.g. bicep muscle is eccentrically contracting as the weight is lowered toward the floor).
3. Isometric (等長收縮) — the resistance and force are even and no movement is taking place (e.g. plank, wall sit).
4. Isotonic (等張收縮) — a muscular contraction performed at the same force throughout range of motion. Isotonic resistance training is the most common method where the resistance remains the same throughout the exercise.
5. Isokinetic (等速收縮) — a muscular contraction in which the rate of force application remains constant (most often seen in a rehabilitative setting using expensive equipment and least common in training for muscular fitness).
It’s not as simple as saying the downward or upward movement is concentric or eccentric as it depends greatly on the exercise being performed and the muscle groups being used.
A force-couple relationship — the concomitant contraction of various muscle groups that produce movement of the human body. These are muscles that contract, not necessarily in the same direction, but together in order to produce a specific movement.
Length-tension relationship — the optimal muscular length at the level of sarcomere for maximum force potential of the muscle.

Question 12

Exercise and The Muscular System

Answer 12

The physiological adaptation to the muscular system are influenced by the implementation of resistance training, flexibility training, and endurance training.
Resistance training — cause an increase in the size of the muscle (a.k.a. muscular hypertrophy).
2 types of hypertrophy developed through resistance training — 1. Sarcoplasmic Hypertrophy (基質肥大): occurs as the sarcoplasmic reticulum and muscle glycogen stores are increased, does not necessarily result in increased force production of the muscle. 2. Myofibrillar Hypertrophy (機緣纖維肥大): an increase in the overall size of the muscle fibers, result in improved muscle cross-sectional area and improved strength.
Muscular strength improvements can be developed without an obligatory increase in muscle size; however, the larger the muscle, the more potential strength it can obtain.
Muscular Atrophy — a decrease in muscle size and strength due to detraining or lack of use (e.g. sedentary lifestyle, injury, or musculoskeletal disorders).
Muscular Hyperplasia (肌肉增生) — an increase in the number of muscle fibers.
DOMS (delayed onset muscle soreness) — a side effect of performing training the overloads the muscles, the post-exercise muscular soreness caused by micro-tears in the muscle fibers. Resistance training is often the culprit of this side effect; however, endurance training can elicit the same effect. The micro-tears provoke a response from the body to adapt and become stronger, preventing further soreness at similar intensities.
DOMS is primarily associated with micro-tears in muscle fibers caused by the eccentric muscular contraction of exercises.
Flexibility training — can be used to influence muscle length if performed consistently. Muscle flexibility improves the range of motion of joints, prevents compensatory movements due to tight muscles, and improves muscle elasticity for activity. Dynamic and static stretching can be performed to improve muscle flexibility.
Dynamic stretching does not necessarily improve long-term range of motion but better prepares individuals for exercise.
Static stretching can help to elongate muscle fibers and improve joint range of motion over time; help improve muscle length-tension relationships by preventing inadequate sarcomere corssbridging caused by excessive actin overlap of myosin.
Flexibility allows for appropriate sarcomere resting length, which promotes optimal length-tension relationship for force production of muscles.

Question 13

The Cardiovascular System

Answer 13

The cardiovascular system is made up of heart, lungs, veins, and arteries.
1. Heart — 4-chambered muscular pump that forces blood to the entire body, has several protective layers that help prevent outside environmental factors from disrupting its rhythm and function: pericardia (心包), epicardium (心外膜), and endocardium (心內膜).
2. Lungs — organs with a vast network of branching airways involving the intake of oxygen from the environment for the blood supply and gas exchange of oxygen and carbon dioxide.
3. Veins — carry deoxygenated blood away from the tissues and organs back to the heart.
4. Arteries — carry oxygenated blood from the heard to the tissues and organs.
These tubes (arteries & veins) start larger in diameter close to the heart and lungs and become smaller as they reach toward the tissues and organs. Arteries become arterioles (小動脈) — smaller branching portion of the artery that allow blood to flow into the capillaries (毛細管), the smallest branch of the circulatory system where gas exchange from blood to tissues occurs.

Question 14

Structure and Form of The Cardiovascular System

Answer 14

Blood — a viscous liquid medium that supports the transport of oxygen to the tissues and the removal of waste products (e.g. carbon dioxide) from the tissues.
The top two chambers of the heart are referred to individually as atrium (新房). The bottom two chambers of the heart are the ventricles (新市).
1. The right atrium is fed deoxygenated blood by two major veins: superior vena cava (上腔靜脈, transports deoxygenated blood from the upper part of the body to the right atrium) and inferior vena cava (下腔靜脈, transports deoxygenated blood from the lower part of the body).
2. The left atrium is fed oxygenated blood from the pulmonary veins from left and right lungs.
Valves (瓣膜) — separating the atrium and ventricles, made of connective tissue that prevent the backflow of blood. Valves also separate the ventricles from the various tubes that carry blood to the rest of the body.
1. Mitral Valve (二尖瓣) — separates the left atrium and ventricle, preventing the backflow of oxygenated blood into the atrium.
2. Tricuspid Valve (三間半) — separates the right atrium and ventricle, preventing backflow of deoxygenated blood into the atrium.
3. Aortic Valve (主動脈瓣) — separates the left ventricle from the aorta (主動脈), allowing for oxygenated blood from the left ventricle to be pumped through the aorta.
4. Pulmonary Valve (肺動脈瓣 aka Pulmonic Valve) — separate the right ventricle from the pulmonary artery, preventing the backflow of deoxygenated blood from the pulmonary artery from entering the right ventricle.
Aorta — the main artery for oxygenated blood transport to the majority of the human body.
Pulmonary Artery — carries deoxygenated blood from the heart to the lungs for gas exchange.
Pulmonary Vein — carries oxygenated blood from the lungs back to the heart for transport to the rest of the body.
Lungs — an organ with a branching system of airways that allow the blood to be oxygenated. Air is inhaled through the mouth and nose and carried down the trachea (企管) to the bronchi (pl. 支氣管). The bronchi bifurcate toward each lung, branching to carry air to either side. From here, the bronchioles (細支氣管) further branch and carry air to the alveoli (pl. 肺泡). The alveoli are tiny air sacs (氣囊) in the lungs that allow for the exchange of oxygen and carbon dioxide with the blood.
Red Blood Cells — contain hemoglobin (血紅素) for the transport of oxygen through the bloodstream to the tissues.
Platelets (血小板) — the element of blood that assists in forming clots (凝血塊).
Diaphragm (隔膜) — a muscle that helps to create a pressure differential in the abdomen and chest which allows air to flow into and out of the lungs when contracting and relaxing, respectively.
The heart and lungs work simultaneously to keep consistent flow of oxygenated blood to the tissues.

Question 15

Pathologies of the Cardiorespiratory System (心肺系統)

Answer 15

The heart has electrical nodes that help determine a healthy heart rate.
Sinus Node (竇房結) — the electrical node of the heart that helps determine the heart rate, located in the right right atrium.
Arrhythmia (心律不整) — disorders affecting the heart’s normal rhythm, causing an abnormal heart rhythm.
Electrocardiogram (心電圖) — a device that can sometimes determine arrhythmias, measures the electrical activity of the heart through a device using nodes placed on the surface of the skin around the heart, can also be used to determine if heart attack is going to occur.
Heart Attacks (aka Myocardial Infarction 心肌梗賽) — the death of heart tissue, typically caused by a lack of blood flow from blockage.
Blood Pressure (BP) — the amount of pressure placed on the walls of the blood vessels by the body’s blood flow, measured in millimeters of mercury (mmHg 毫米汞柱), determined using a sphygmomanometer (血壓計). The number is red as systolic blood pressure over diastolic blood pressure, and a healthy guidance is 120 over 80 mmHg.
Systolic Blood Pressure (收縮壓) — the top number of a BP reading indicating the maximal amount of pressure placed on the arteries following contraction of the left ventricle.
Diastolic Blood Pressure (舒張壓) — the bottom number of a BP reading indicating the lowest amount of pressure placed on the arteries as the ventricles relax.
To improve consistency with blood pressure readings, the process should be performed from a seated position and on the right arm each time. When checking clients’ BP readings while they are sitting, one must ensure that the clients’ feet are not crossed as this can artificially increase BP readings.
Hypertension — increased BP, above 140/80 mmHg
Hypotension — decreased BP, below 90/60 mmHg.
Clients presenting either of the hypertension or hypotension prior to starting an exercise should seek a physician for exercise clearance.
Atherosclerosis (動脈粥狀硬化) — can increase the risk of having a severe cardiovascular event like a heart attack or stroke, a disease characterized by hardening or narrowing of the arteries due to plaque deposits (斑塊沉積物). A physician’s clearance should always be obtained prior to starting a program, and the trainer should make sure to monitor for signs of a stroke or heart attack during sessions.
Asthma — a chronic disease affecting breathing and is due to inflammation of the respiratory airways of the body.
Chronic Obstructive Pulmonary Disease (COPD) — a broad definition of many disease causing chronic obstruction of airflow to the lungs, including emphysema (氣腫), asthma, and bronchitis (支氣管炎).
Emphysema — a COPD characterized by damage to the alveoli and subsequent entrapment of air (空氣滯留) and eventual breaking of the air sacs. This disease can increase an individual’s residual capacity, which is the air remaining in the lungs following an expiration of exhaling. The remaining air becomes stale and makes it difficult to breathe.
These COPDs are often caused by smoking or exposure to pollution and chemicals that can damage the airways.

Question 16

Effects of Exercise on the Cardiovascular System

Answer 16

Common acute response as exercise rises in intensity: an increased heart rate and hyperventilation (過度換氣).
Hyperventilation — increased breathing rate, due to the body requiring a larger supply of oxygen to produce energy in the form of ATP required for exercise. Additionally, the heart must pump faster to supply the blood that carries the oxygen to the muscles.
Acute cardiovascular response to exercise — an increase in systolic BP (However, there is very little change to diastolic BP), increased cardiac output by the heart, and the shunting (分流) of blood to working musculature and away from the areas that are less utilized.
Long-term cardiovascular physiological adaptations to aerobic exercise include — improved heart efficiency (due to the improved stroke volume meaning the heart pumps more blood to the body in one beat), increased heart size, increased capillary density, decreased BP, and increased blood volume.
BP can vary due to postural changes, based on whether the client is lying, sitting, or standing.
Orthostatic Hypotension (姿勢性低血壓) — a drop in BP due to postural changes, mostly due to dehydration. It’s important for the trainer to understand why this is happening because it’s common during workouts to go from prone/supine to standing positions (BP first dips slightly and then increases dramatically to compensate for the change in body position).

Question 17

The Nervous System

Answer 17

The Nervous System is typically broke down into 2 parts:
1. Central Nervous System (CNS) — made up of the brain and spinal cord. The brain is an organ of the CNS made up of nervous tissue, responsible for nearly all thought processes and actions of the human body. The spinal cord is responsible for the relaying of info to and from the rest of the body to the brain. The spinal cord is protected by the vertebral column (脊椎): a structure of bones that enclose the delicate nervous tissue.
2. Peripheral Nervous System (PNS 周邊神經系統) —
Neurons (Nerve Cells) — involved in the transmission of electrical impulses through conductivity (導電性) and input from internal and external stimuli. Neurons have a nucleus (和) and transmit these electrical impulses through their axons (軸突) and dendrites (樹突).
The axon is a stem-like structure that carry info to other neurons throughout the body. Dendrites are the branching system on neuron’s body that receive info from other neurons.
The functions of the nervous system can be broken down into:
1. Autonomic Nervous System (自主神經系統) — controls involuntary actions (e.g. respiration, heartbeat, digestive processes, etc.)
2. Somatic Nervous System (軀體神經系統) — associated with the body’s ability to control skeletal muscle and voluntary movement as well as the involuntary reflexes associated with skeletal muscles.
The Autonomic Nervous System break down even further into:
1. Sympathetic Nervous System (交感神經系統) — responsible for the body’s reaction to stress and induces a “fight-or-flight” response to stimuli.
2. Parasympathetic Nervous System (副交感神經系統) — stimulated by the body’s need for rest or recovery, responds by decreasing heart rate/BP/muscular activation when a person is getting ready to sleep, digesting food, etc. The body reacts to eating a large meal by activating the parasympathetic nervous system, which is why people feel sluggish after eating a large meal.

Question 18

Pathologies of the Nervous System
Effects of Exercise on the Nervous System

Answer 18

Epilepsy (癲癇) — a chronic disease involving episodic seizure (陣發性癲癇) due to disruption of the CNS, can occur at all stages of life.
A number of causes can induce the seizures that are involved in epileptic syndromes, including: strokes, autism, traumatic brain injury, genetic disorders, developmental disorders, and even Alzheimer’s disease.
Alzheimer’s disease — characterized by the loss of memory and deteriorating cognitive function, usually later in life, due to the degeneration (退化) of neurons in the brain. The disease is a form of dementia (失智) that progresses gradually and has no known cure.
Multiple Sclerosis (MS 多發性硬化症) — involves the gradual breakdown and scarring of the myelin sheaths (隨俏) surrounding axons due to immune system attacks in a neuron, causing disruption of nervous transmission of impulses. This disease is thought to be genetic and there’s no known cure.
Myelin Sheaths — surrounding the axon, help speed up the process of nervous electrical transmission.
The nerve damage associated with MS causes vision trouble, difficulty walking, fatigue, pain, involuntary spasms, and numerous other symptoms.
Exercise helps improve the efficiency of the nervous system’s connection to the muscle, esp. by performing resistance training exercises regularly. The muscles are placed under excessive levels of stress, and the nervous system adapts by recruiting more motor units to perform the same movement. The result is an increase in strength within the first weeks of resistance training. Conduction of a nervous impulse to muscle creates the muscular contractions that assist in human movement.
Motor Unit Recruitment — the process of stimulating more motor units to overcome a force. If a load is too heavy, more motor units are stimulated by the nervous system to induce a stronger muscular contraction.
The force of a muscular contraction is determined by the nervous system’s stimulation of either more motor units or its consistent stimulation of a muscle.
When resistance training exercise is performed properly and consistently, the body makes neuromuscular adaptations that improve strength. Motor unit recruitment becomes more efficient, allowing the body to lift heavier loads. The nervous system will first recruit type I muscle fibers. However, if these fibers are not sufficient to move the force, type II fibers will be recruited to assist.
The pattern of nerve conduction follows these steps:
1. An impulse travels from the brain to the end of the axon at the synapse with a muscle cell.
2. The neurotransmitter (神經傳導物質), acetylcholine (乙烯膽鹼), is released into the synaptic cleft (突觸間隙).
3. The acetylcholine is received by the sarcolemma (肌膜) of muscle.
4. Action potential（動作店為）in muscle is triggered.
5. Action potential initiates the release of calcium from the sarcoplasmic reticulum of a muscle cell.
6. Calcium exposes the thin actin filaments of muscle to the think myosin filament heads for attachment.
7. Myosin crossbridging occurs.
8. Muscular contraction results from crossbridging and flexion of myosin heads on actin.

Question 19

The Endocrine System
Structure and Form
Effects of Exercise

Answer 19

The Endocrine System — made up of a varietal system of glands with the purpose of regulating numerous processes throughout the body via secretion of hormones.
Gland – an organ associated with controlling the release of chemical substances, known as hormones, for the regulation of metabolic processes, growth and development, sexual reproduction, and other bodily functions.
Hormones — the chemical substances used for controlling different bodily and cellular processes released by the glands.
Hypothalamus (下視丘) — a gland found in the brain, responsible for the control of the ANS’s function and the connection between the CNS and the endocrine system. It’s important because of its control of the body’s life-sustaining processes that are regulated by the ANS.
Pituitary gland (腦下垂體) — found at the base of the brain, responsible for the release of hormones (HGH which regulates muscle and bone development) that regulate human growth and development.
Pineal Gland (松果體) — regulates the body’s sleep processes through the release of the hormone melatonin (退黑激素).
Parathyroid Gland (副甲狀腺) — located near the thyroid gland, stores and secretes parathyroid hormones responsible for the regulation of the body’s calcium levels, which determines things like bone mineral density.
Adrenal Glands (腎上腺) — located superior to the kidneys, produce epinephrine (腎上腺素), norepinephrine (去甲腎上腺素), cortisol (皮質醇), and aldosterone (醛固酮).
Epinephrine — a hormone responsible for the regulation of heart rate, BP, and more due to autonomic responses to stimuli.
Cortisol — a hormone responsible for the regulation of the processes when stress is placed on the body. It increases blood sugar, macronutrient metabolism, and more during times of stress.
Pancreas (胰臟) — found in the abdomen, responsible for the secretion of a digestive substance into the duodenum (十二指腸) of the small intestine and the regulation of insulin and other hormones.
The regulation of insulin is important because it is how the body controls blood sugar levels. During exercise, the body utilizes the glycogen stores in the muscles, which results in a drop in blood glucose levels.
Testes (pl. 睪丸) — male reproductive organs that produce sperm and androgens (雄激素) for reproduction.
Ovaries (卵巢) — female reproductive organs that produce ova and female hormones for reproduction.
Testosterone (睪固酮) — a hormone secreted mainly by the testes that regulates the growth of muscle mass, body hair, bone mass, etc., responsible for the development of male reproductive organs while fetal development is occurring. The absence of this hormone in sufficient quantities to produce male sex organs will result in female reproductive organ development.
Placenta (胎盤) — a part of the uterus (子宮) during pregnancy that passes nutrition and nourishment to the fetus from the mother via the umbilicus (幾代). It produces and develops several hormones responsible for fetal growth and preparatory hormones for motherhood, such as lactogen (催乳素) for breastfeeding.
Many of the important hormones associated with exercise science can be broken down into either anabolic hormones or catabolic hormones.
1. Anabolic Hormones (合成代謝激素) — associated with the regulation of growth and development (e.g. testosterone, estrogen (雌激素), insulin, human growth hormone (HGH), and insulin-like growth factor (IGF 類胰島素生長因子: a hormone synthesized in the liver that aids in tissue growth and many other functions).
2. Catabolic Hormones (分解代謝激素) — associated with the regulation of breaking down substances in the body into smaller molecules (e.g. the breakdown of muscle glycogen for energy via the release of glucagon (一高血糖素) is a catabolic process).
Anabolic steroids can increase the rate and size of muscle mass production, but with significant and dangerous side effects (e.g. negative effects on reproductive organ function, psychological side effects (like depression and mood swings), and severe damage to the liver.
The neuroendocrine response is essentially how the body responds to high intensity exercises with the release of specific hormones that elicit performance gains. This response also occurs as a sort of “fight-or-flight” mechanism in stressful situations. Specifically, when the body is placed under stress, the endocrine system releases cortisol to stimulate production of epinephrine and norepinephrine in response.
The neuroendocrine response to working larger muscle groups (e.g. barbell back squat) provokes a release of anabolic hormones associated with increased muscular hypertrophy and muscular strength. These hormones include: HGH, IGF-1, testosterone, and catecholamines (而查分安).
1. HGH — plays an important role in muscular development and lipolysis.
2. IGF-1 — help maintain and repair muscle.
3. Testosterone — help improve muscular strength and the muscle’s ability to maintain peak strength output.
4. Catecholamines — assist in muscular strength output and improve muscle energy stores and the rate of muscular contraction.
Improvement to the neuroendocrine response to exercise require a progression of exercise intensity involving large muscle groups and high-intensity exercise.

Question 20

The Digestive System
Structure and Form

Answer 20

The digestive system — a tube that extends through the body used for the breakdown of food and the absorption of nutrients. Digestion and absorption of nutrients provide the body with the fuel to maintain homeostasis (體內平衡) and produce human movement.
The digestive system starts at the mouth and ends at the anus:
1. Mouth — allows for the consumption and mastication (咀嚼) of nutrients via an opening in the face. It contains the tongue and uses a substance called saliva (唾液) to assist in the first processes of breaking down food.
1.1. Tongue — a large muscle for the movement of food for mastication by the teeth, and contains taste sensory organs.
1.2. Saliva — the liquid solution secreted by the salivary glands (唾液縣) to assist in the digestion of food through salivary enzymes.
2. Esophagus (食道) — part of the digestive tract leading from the mouth to the stomach that transports food via peristalsis (蠕動).
2.1. Peristalsis — the contraction of smooth muscle found in the digestive tract for moving food.
3. Stomach — an organ of the digestive tract found in the abdominal cavity (腹腔), mixes food with powerful acidic liquid for further digestion. Once the stomach has created an acidic bolus of digested food known as chyme (時迷), it travels to the small intestine where a significant amount of nutrient absorption takes place.
4. Small Intestine — a tube-like structure of the digestive tract containing millions of finger-like projections (突出部分) known as villi (絨毛) and microvilli to increase surface area for the absorption of nutrients. The small intestine then transports food to the large intestine.
5. Large Intestine — similarly tube-like but larger in diameter than the small intestine, assist in further nutrient absorption, water absorption, waste collection, and the production of feces (糞便) for excretion.
6. Rectum (直腸) and Anus — responsible for the storage of feces and removal of feces, respectively.
Along the digestive tract are several muscular rings, known as sphincters (括約肌), and additional organs to aid in digestion. The muscular rings help regulate the movement of digestive food through the digestive tract:
1. Anus — the sphincter between the rectum and the outside of the body.
2. Upper Esophageal Sphincter —between the mouth and esophagus.
3. Lower Esophageal Sphincter — between the esophagus and the stomach.
4. Pyloric Sphincter (幽門括約肌) — between stomach and first portion of the small intestine.
5. Ileocecal Sphincter (回忙不括約肌) — between the small intestine and large intestine.
Bile (膽汁) — created by liver and stored in gallbladder (膽囊). The acidic bolus of food created by the stomach’s digestive juices is buffered by bile.
Liver — an organ located in the abdomen involved in many processes of the body, including: the cleansing of blood, the creation of bile for digestion, the processing of toxins in the body, etc.
Gallbladder (膽囊) — stores and distributes bile to be released into the small intestine to mitigate the acidic PH of the chyme.
Pancreas — aids in the production of enzymes utilized in the digestive process, develops insulin that regulates blood sugar.
Blood sugar is an important factor to monitor during exercise as drops and spikes in blood sugar can be dangerous. Exercise can cause significant fluctuations in blood sugar in those who suffer from diseases that affect pancreas, like diabetes which can result in the individual feeling light-headed or dizzy, faint, overheated, and more dangerous scenarios.
The absorption of nutrients during the digestive process primarily takes place in the small intestine. The mouth and stomach are responsible for the breakdown of food that make the digestive process easier.
Only certain things are absorbed by the stomach, one of which is alcohol.
Some water and minerals are passed through to the large intestine where they continue to be absorbed back into the bloodstream.

Question 21

Biomechanics (生物力學)
Human Kinetics and Lever Systems (人體動力學和槓桿系統)
Strength and Power (功率)

Answer 21

To move, the body creates a system of levers out of the components of the musculoskeletal system.
Lever — the arrangement of resistance (aka resistive force, e.g. weight), force (e.g. muscular contraction), and the fulcrum (支點, e.g. joint) around which movement is achieved. Essentially, the muscle pull on the tendons attached to the bones to create torque (扭力) around a joint, where torque is the rotational force created when the limb is moved through its range of motion to move a resistance.
Mechanical Advantage — the efficiency of the lever based on where the forces are applied. Levers work on a system of mechanical advantage to provide certain types of movement (e.g. calf raise exercise allows for the mechanical advantage of strength while bicep curl allows for a mechanical advantage for speed).
The type of lever often determines what mechanical advantage the joint will have when exercising. There are 3 principal types of levers found in the human body:
1. First-class Levers (一級槓桿) — a lever system where the muscle force and resistive force are at opposite sides of the fulcrum (e.g. the head resting on the 1st vertebrae: the skull is the resistive force. the fulcrum is the C1 cervical vertebrae, and the muscles of the back of the neck are the muscle force).
2. Second-class Levers — a lever system where the muscle force is placed further from the fulcrum than the resistive force, provides the mechanical advantage of strength (e.g. ankle joint: the fulcrum is the ball of the foot, the muscular force is the gastrocnemius and soleus muscles, and the resistive force is the body weight and additional weight being lifted).
3. Third-class Levers — a lever system where the muscle force is placed closer to the fulcrum than the resistive force, provides the mechanical advantage of speed, most common lever systems found in the body (e.g. knee (flexed by hamstrings) (or elbow flexed by biceps) — the fulcrum is the knee joint, the muscular forces are the hamstrings and its tendinous attachment, and the resistive force is the lower portion of the leg and foot.
Mass (質量) — the amount of matter that any particular object is made up of, typically measured in kilograms.
Force — the mass of an object x its acceleration, where acceleration is the rate of increase in velocity.
Velocity — the rate at which an object is traveling, including its direction and magnitude. Another way to describe velocity is the rate at which an object travels a specific distance.
Newton’s 3 laws of motion that describe the physics surrounding objects that are moving:
1. 1st law of motion — objects in motion will either remain in a state of motion or state of rest until acted on by outside forces. This concept explains the change from resting to motion by an outside force.
2. 2nd law of motion — the mass of the object determines the amount of force required for its acceleration (Force = Mass x Acceleration), explains the fundamental concept of resistance training (e.g. Mass = weight, Force = muscle force, Acceleration = the rate of the moving weight).
3. 3rd law of motion —when an action occurs, there are reactions that are equal yet opposite (e.g. when striking a tennis ball with the racket).
Power (功率) — the ability to perform work (公) divided by the time it takes to perform that work (During exercise, work is being performed to life weights when a force is applied to an object to move it over a distance).
Momentum (動量) — Mass (of an object) * Velocity (it’s traveling).
Impulse (衝量) — (the amount of) Force * Time (the force is applied).
Rotational Work (旋轉公) — the amount of muscular force (force) needed to move an object through a joint’s angular range of motion (distance)
Rotational Power — the amount of work being done by the muscles (work) at a joint divided by the rate at which they are applied (time).
Angular Velocity (腳速度) — the rate at which a muscle produces movement through full range of motion at a joint.
Some important physics equations that relate to the principles of biomechanics:
1. Force = Mass * Acceleration
2. Acceleration = Change in Velocity /Change in Time
3. Velocity = Distance / Time
4. Work = Force * Distance
5. Power = Work / Time = Force * Distance / Time = Force * Velocity
6. Momentum = Mass * Velocity
7, Impulse = Force * Time
Strength — unlike Power, it does not have a time component and is simply the all-out effort from the muscle, often measured via a 1RM test which is the ability to complete one full repetition without compensation to determine strength in a particular movement.
Force-Velocity Curve — the inversely proportional relationship between the amount of force required to move an object at a specific rate and the rate at which the object moves (velocity). As the amount of force from the muscle increases, the velocity of the movement will decrease and vice versa.
Force-Time Curve — represents the time it takes to reach peak force output by the muscles.

Question 22

Bioenergetics (生物能量學)

Answer 22

Bioenergetics — describe the processes by which the body converts energy for different uses, explains how the body is able to utilize various fuel sources for movement.
ATP (Adenosine Triphosphate) — the basic energy unit required by the body to perform movement and other metabolic processes. In order for the body to function, it must create units of ATP.
Metabolism — the chemical reaction that build and break down the various tissues of the body to sustain life. There are 2 types of metabolic processes:
1. Anabolism (合成代謝) — the metabolic processes that require energy to build up molecules.
2. Catabolism (分解代謝) — the metabolic processes that breaks down larger molecules into smaller ones.
The human body relies primarily on 2 major energy systems for exercise:
1. Aerobic Energy System — the ability of the human body to convert macronutrients into ATP through multiple metabolic processes in the presence of oxygen for sustained duration. This energy system is primarily utilized for longer-duration activities (e.g. cycling, running, swimming, etc.).
2. Anaerobic Energy System — the ability of the body to produce ATP via creatine phosphate (磷酸肌酸) or muscle glycogen stores. This energy system is primarily utilized for shorter-duration activities (e.g. weightlifting, sprinting, jumping, etc.). The body can produce ATP through anaerobic processes more rapidly.
The Krebs Cycle and Electron Transport Chain (ETC 墊子傳遞練) are where the body creates its ATP for energy.
1. The Krebs Cycle — an aerobic metabolic breakdown of macronutrients in the body by mitochondria to form carbon dioxide and ATP. Glycolysis (堂姊), the ability of the body to break down blood glucose and muscle glycogen stores for the creation of ATP, occurs in the body to create a coenzyme called Acetyl Coenzyme A (Acetyl CoA) that is used in the Krebs cycle.
2. Electron Transport Chain (ETC) — a portion of the aerobic metabolic process of the Krebs cycle where NADH and FADH2 are used to transfer hydrogen ions to oxygen, forming water and releasing energy in the form of ADP, which is converted to ATP, supplying additional energy to the body. ETC can produce an additional 34 ATP as a result of the Krebs cycle metabolizing acetyl CoA.
Glucose — sugars found in the body and bloodstream.
Glycogen — a glucose-based energy supply, typically synthesized and stored in the liver and skeletal muscle.
Acetyl CoA enters the Krebs cycle to produce a number of byproducts:
1. two molecules of ATP (utilized to fuel the body)
2. four molecules of carbon dioxide (released through respiration)
3. six molecules of NADH (nicotinamide adenine dinucleotide)
4. two FADH2 (二磷酸線桿) molecules (The molecules of NADH and FADH2 are sent through the ETC to produce additional ATP)
Creatine Phosphate — utilized to synthesize ATP rapidly, an energy source used by the body in the first seconds of exercise.
The Phosphagen System (磷酸元系統) — produce ATP for high intensity exercise at short durations of 10 secs or less.
Bouts of intense exercise using the phosphagen system tend to create byproducts that hinder performance at this intensity for long durations. One such byproduct is called lactic acid (乳酸).
Lactic Acid — builds up in the bloodstream when anaerobic glycolysis produces hydrogen ions in the bloodstream due to lack of oxygen uptake to meet the needs to the exercising muscle. The hydrogen ions decrease the pH of the blood in the muscles, causing an intense burning sensation the limits performance.
Training at high intensities helps mitigate the onset of lactic acid buildup, thereby improving the client’s lactate threshold, which is the maximal rate at which lactic acid due to exercise can be buffered from the bloodstream. Highly trained athletes have a higher lactate threshold and are able to withstand higher intensities of exercise for longer durations.
Oxygen Uptake (攝氧量) —Training can also help improve an individual’s oxygen uptake, which is the ability of the body to consume and utilize oxygen.
Oxygen Deficit (缺氧) — at the start of the exercise, the body undergoes an oxygen deficit and will start to ventilate more quickly to catch up demands. The oxygen deficit is the necessitation of anaerobic processes to supply energy at the start of an exercise session until the oxygen uptake reaches a steady state.
Oxygen Debt (氧氣債) — occurs immediately following exercise and is the excessive consumption of oxygen to return the body to a resting state. Metabolism following a bout of intense exercise remains at elevated rate for a short period of time.
Excess post-exercise oxygen consumption (EPOC) — one of the metabolic processes of bioenergetics that occurs following exercise, similar to oxygen debt and referring to the body’s continued consumption of oxygen following exercise for a full return to homeostasis. This continued oxygen consumption results in more energy expenditure even at rest and is a highly beneficial side effect of exercise for weight loss.

Question 23

Training Differences Among Athletes
Children
Female Athletes
Older Adults

Answer 23

Fitness professionals should be aware of the common anatomical and physiological differences among individuals of different ages, genders, and training status.
Males tend to develop upper body strength more easily when compared to females, whereas females tend to develop lower body strength more easily.
Females tend to develop a knock-knee (內八字腿) more often than males due to the anatomical difference in pelvis width compared to knee location. The wider pelvis places more medial (內側的) stress on the knee when performing squats or landing from a jump.
Athletes who have been training for a longer period of their life will require a more challenging fitness program to meet their needs and elicit performance gains.
Children can perform resistance training safely; however, they require more supervision and lower intensities. The exercise should be performed in an effort to learn and develop technique and coordination rather than focus on increasing resistance and strength.
Training children should also incorporate a well-rounded program that includes all the major muscle groups of the body in multiple planes of motion. Cardiovascular activity should be performed through a variety of activities as this will help prevent any long-term overuse through specialization in sport. Encouraging kids to try many different forms of exercise will benefit them more in the long-term.
Prior to adolescence, children will not develop muscle quite as rapidly, their coordination will not be as well developed, and they will have difficulty regulating body temperature. Their coordination will struggle due to the changing width of their base of support and the height of their center of gravity. To combat poor thermoregulation in children, the fitness professional should encourage taking water breaks often and try to educate young clients to drink plenty of fluids prior to beginning their workouts.
Female Athlete Triad — the deleterious effects of over-exercising among female athletes and consists of 3 signs and symptoms: amenorrhea (必經), early osteoporosis, and disordered eating habits. Typically this cycle begins with a lack of proper nutritional intake brought about by a desire to look different or a restrictive diet in order to cut weight with assumption that it will improve performance. The trainer should develop and discuss an appropriate caloric intake to help prevent the female athlete from falling into a pattern of disordered eating if calories are being restricted.
Disordered eating, like anorexia (厭食症) or bulimia (暴食症), can cause further potential dangers, leading to the other two indicators of the triad.
Amenorrhea — a cessation of the menstrual cycle over a 3-month period. This is due to the dramatically insufficient caloric intake and a drop in estrogen levels. These low estrogen level lead to the final point of the triad: decreased bone mineral density and early onset osteoporosis (早發性骨質疏鬆症).
Estrogen (雌激素) — a hormone that helps keep bones strong in females.
Generally, the female body tends to carry more of its muscle mass in the lower body than the male body. The female body also carries extra adipose tissue - necessary for a healthy body composition - and has a wider pelvis and subsequent difference in hip and knee biomechanics. Due to differences in muscle mass development, it’s not uncommon for females to lift significantly less resistance during certain upper body exercises.
Female athletes should be instructed not to decrease caloric intake too dramatically and should keep in mind a healthy body fat composition for females is around 20%.
A wider pelvis in females comes with a subsequent biomechanical difference in the Q angle at the hip joint. This is important because wider Q angle can lead to more pressure on the medial aspect of the knee joint in females. Femail athletes who participate in sports that require constant jumping, such as volleyball and basketball, are at a higher risk of knee injuries due to this biomechanical disadvantage.
The trainer must take this difference into consideration and inform the female athlete of proper jumping and landing mechanics. The trainer should make arrangements to evenly strengthen the musculature of the legs in order to prevent further exacerbating this increased medial knee stress upon landing.
The female pelvis width creates a larger Q angle and can negatively affect the ligaments of the knee if added force is applied medially.
A trainer must take into account the effect that aging has on the body prior to developing a well-rounded training program. Prior to starting a fitness program, the trainer should implement an assessment process that includes PAR-Q and a thorough medical history to identify any concerns that should be addressed by a client’s physician.
Bones and muscles are more flexible and recover more quickly as children. Muscles become less flexible as we age due to sedentary career choices and lifestyle changes. — Taking this into account, training older adults should include more time spent warming up the muscles to make them more pliable (柔韌的) and ready for activity. Training programs for older adults should also include an increased focus on developing stability to reduce the risk of falls.
Aging also influences the cardiovascular and nervous systems. As people grow older, their maximal heart rate decreases, making it necessary to adjust target heart rates during exercise. It’s also important to determine whether the individual is healthy enough for exercise prior to starting a cardiovascular training program. For example, atherosclerosis (動脈粥狀硬化) is developed over years of plaque buildup in the arteries and generally occurs more often in older adults.
Like the muscular system, the nervous system also goes through stages of atrophy with older adults. This means training may require reiterating certain techniques over the course of a training program.
Falls in older adults often occur due to breaks that happen before they hit the ground due to loss of bone mineral density.
Resistance training and exercises that involve impact can help subdue (阻止) the onset of osteoporosis in older adults and help improve balance.
Although flexibility diminishes significantly as people age, it can help reduce common postural and biomechanical deviations that cause aches and pains.
Cardiovascular training also benefits older adults as it strengthens their heart and lungs and help reduce the risk of heart attack or stroke.
The benefits of training outweigh the risks of a sedentary lifestyle, even in older population.