T4-6 4.1 - Neuromuscular Function Assessment 4.1.1 - Motor Unit Diagram Key components of a motor unit include: Dendrite Cell Body Nucleus Axon Motor End Plate Synapse Muscle 4.1.2 - Role of Neurotransmitters Neurotransmitters : Chemicals for neuron communication at the synapse. Acetylcholine : Transfers action potential from motor unit to muscle cells, triggering contraction. Converts electrical impulses to chemical stimuli at the motor end plate. Increases membrane permeability to sodium ions, leading to calcium release in muscle cells. Cholinesterase : Enzyme breaking down acetylcholine. Stops muscle contraction by causing membrane depolarization. 4.1.3 - Sliding Filament Theory Muscle contraction is initiated by nervous impulses. Key Terms : Myofibrils : Units within muscle fibers containing actin and myosin. Myofilaments : Thick & thin filaments of actin and myosin. Sarcomere : Basic unit of muscle contraction. Actin : Thin protein filaments. Myosin : Thick protein filaments with heads that form cross-bridges with actin. H Zone : Zone of myosin only (no overlap with actin). A Band : Length of myosin, includes the overlap with actin. Z Line : Boundary of sarcomeres. Tropomyosin : Protein covering active sites on actin, preventing myosin binding. Troponin : Protein that binds with calcium to move tropomyosin aside, allowing contraction. Sarcoplasmic Reticulum : Stores calcium ions. Calcium Ions : Trigger contraction when released. ATP : Energy source for muscle contraction. Process : Calcium released upon nerve impulse stimulates contraction. Tropomyosin shifts, exposing actin’s active site. Myosin heads bind to active sites forming cross-bridges. ATP breakdown provides energy for the myosin heads to pull actin filaments inward, shortening the muscle. Muscle relaxation occurs when calcium ions are removed. 4.1.4 - Skeletal Muscle Fiber Types Slow-Twitch (Type I) : Structure: High myoglobin, more mitochondria. Function: Endurance activities (aerobic). Fast-Twitch (Type IIa & IIb) : Structure: Lower myoglobin, fewer mitochondria. Function: Short bursts of speed and power. Type IIa : Intermediate fiber, high glycogen stores. Type IIb : Primarily glycolytic, fatigue quickly, high glycogen content. 4.2 - Joint and Movement Type Assessment 4.2.1 - Types of Movement of Synovial Joints Flexion : Decreasing angle between body parts. Extension : Increasing angle between body parts. Abduction : Movement away from the median plane. Adduction : Movement towards the median plane. Pronation : Palms facing downwards. Supination : Palms facing upwards. Elevation : Raising a body part. Depression : Lowering a body part. Rotation : Turning around an axis. Circumduction : Circular movement of a limb. Dorsiflexion : Lifting the foot. Plantar Flexion : Pointing the toes. Eversion : Rolling the ankle outward. Inversion : Rolling the ankle inward. 4.2.2 - Types of Muscle Contraction Isotonic : Muscle changes length and causes movement. Concentric : Muscle shortens (e.g. bicep curl). Eccentric : Muscle lengthens (e.g. decelerating during a kick). Isometric : Muscle tension without length change (e.g. holding an object). Isokinetic : Movement at a constant speed (used in rehabilitation). 4.2.3 - Reciprocal Inhibition Agonist : The muscle primarily responsible for movement. Antagonist : The muscle that relaxes to allow movement to occur. 4.2.4 - Movements in Joint Action and Muscle Contraction Example: Bicep curl: Agonist is the bicep (contracts concentrically), antagonist is the tricep (relaxes eccentrically). 4.2.5 - Delayed Onset Muscle Soreness (DOMS) DOMS occurs after intense exercise, especially eccentric actions. Caused by: Micro-tears in muscle Inflammatory response Overstretching Overtraining Symptoms appear 24-72 hours post-exercise. Prevention: Decrease intensity during early training. Gradual increase in intensity. Proper warm-ups and cool-downs. 4.3 - Fundamentals of Biomechanics Assessment 4.3.1 - Key Terms in Biomechanics Force : Interaction between two objects. Speed : Rate of motion. Velocity : Speed with directional component. Displacement : Distance moved in a particular direction. Acceleration : Rate of change in velocity. Momentum : Mass in motion. Impulse : Product of force and time. Scalars : Measurements with magnitude only. Vectors : Measurements with both magnitude and direction. 4.3.2 - Graph Analysis Velocity-Time Graph : Shows constant acceleration, constant velocity, and deceleration. Distance-Time Graph : Displays distance covered over time intervals. Force-Time Graph : Details the impulse of a force, showcasing changes during a performance. 4.3.3 - Center of Mass Definition: The point where mass is evenly distributed. Factors: Men generally have a higher center than women. Center can be outside the body during certain movements (e.g., Fosbury Flop). 4.3.4 - Body Position in Sports Center changes based on position during movements, impacting stability and performance. Examples: Activity with center of mass within: Running. Activity with center of mass outside: High Jump. 4.3.5- 4.3.6 - Levers in the Body First Class Lever : Load, fulcrum, force (e.g., neck extension). Second Class Lever : Force, load, fulcrum (e.g., calf raises). Third Class Lever : Fulcrum, force, load (e.g., bicep curl). Lever diagram includes triceps-elbow, calf-ankle, and biceps-elbow examples. 4.3.7 - Newton’s Laws of Motion Inertia : Objects at rest stay at rest unless acted on. Acceleration : Mass and acceleration influence force (F = ma). Action-Reaction : For every action, there is an equal and opposite reaction. 4.3.8 - Laws of Motion in Sports Newton’s laws describe motion in activities like sprint starts and jumps. Impulse-momentum relationship and conservation of momentum are crucial for performance. 4.3.9 - Angular Momentum Concept Angular Momentum : Measure of rotation. Angular Momentum = Angular Velocity imes Moment of Inertia. 4.3.10 - Angular Momentum in Sports Changes in body position affect moment of inertia and angular velocity, exemplified by gymnasts. 4.3.11 - Factors in Projectile Motion Includes: speed, height, and angle of release. 4.3.12 - Bernoulli Principle Describes effects of airflow on projectile motion. States that higher airflow leads to lower pressure and results in lift on spinning objects (e.g., golf ball). 5.1 - Characteristics and Classification of Skill 5.1.1 - Definition of Skill Skill is the execution of learned movements directed at a goal (McMorris 2004). 5.1.2 - Types of Skill Cognitive : Problem-solving abilities. Perceptual : Interpreting sensory information. Motor : Execution of physical skills. Perceptual Motor : Combination of thought/interpretation and movement. 5.1.3 - Motor Skill Classifications (i) Gross-Fine : Whole body vs. specific movements (e.g., kicking vs. writing). (ii) Open-Closed : Environment influenced vs. stationary actions (e.g., football vs. free throw). (iii) Discrete-Serial-Continuous : Defined start/end, sequence, or cyclical (e.g., jump, dance). (iv) Externally-Internally Paced : Timing dictated by environment vs. performer (e.g., javelin vs. swimming). (v) Interaction Continuum : Individual, coactive, interactive. 5.1.4 - Skill Profiles in Sports Compare sporting skills across classifications. 5.1.5 - Ability Definition Ability is a capacity that relates to performing various skills. 5.1.6 - Fleishman’s Abilities Distinction between physical proficiency abilities (related to fitness) and perceptual-motor abilities (skill-related). 5.1.7 - Technique Definition Technique: the specific method of performing a skill. 5.1.8 - Relationship Between Ability, Skill, and Technique Skill = Ability + Selecting Appropriate Technique. Comparison factors: consistency, accuracy, control, learning stage, efficiency, goal direction, and fluency. Model: Input-Decision Making-Output. 5.2.2 - Welford’s Model Steps: Sensory input, perception, short/long-term memory, decision-making, effector control, feedback. Exteroceptors : External environment info. Proprioceptors : Body position and movement. Interoceptors : Internal body signals. 5.2.4 - Signal Detection Process Steps: Detection-Comparison-Recognition (DCR). Influenced by noise, stimulus intensity, and sensory efficiency. 5.2.5 - Memory Characteristics Short-Term Sensory Store : Immediate input, <1 second duration. Short-Term Memory : Holds 5-9 items for seconds. Long-Term Memory : Unlimited capacity, retains information for long periods. 5.2.6 - Selective Attention and Memory Selective Attention filters relevant information to avoid overload, crucial for performance. 5.2.7 - Memory Improvement Techniques Methods: rehearsal, coding, clarity, chunking, organization, brevity. 5.2.8 - Response Time Definition Response Time = Reaction Time + Movement Time. 5.2.9 - Response Time Influencing Factors Factors: sex, age, fitness, fatigue, personality, number of stimuli, intensity of stimuli, length of neural pathways. Hick’s Law applies. 5.2.10 - Psychological Refractory Period Evaluation PRP : Delay caused by responding to multiple stimuli; emphasizes single task processing. 5.2.11 - Motor Programme Definition Motor programmes are entire movement patterns stored in memory. 5.2.12 - Open vs. Closed Loop Open Loop : Fast actions with no feedback (e.g. serves). Closed Loop : Continuous feedback and adjustments (e.g. cycling, running). 5.2.13 - Feedback Role Types: intrinsic, extrinsic, results knowledge, performance knowledge. 5.2.14 - Feedback Learning Process Role Importance: reinforces learning, motivates, adapts performance, provides constructive criticism. 5.3 - Principle of Skill Learning Learning : Permanent improvement from practice. Performance : Temporary and fluctuating outcomes. 5.3.2 - Learning Phases Cognitive/Verbal : Initial stage, basic comprehension. Associative/Motor : Refinement and increased consistency. Autonomous : Highly skilled with less conscious control. 5.3.3 - Learning Curves Types: positive acceleration, negative acceleration, linear, plateau. 5.3.4 - Factors in Learning Rates Individual differences, age, motivation, task difficulty, environment impact. 5.3.5 - Transfer Concept Ability to apply learned skills to new contexts. 5.3.6 - Transfer Types Positive, negative, zero, skill to skill, practice to performance, ability to skill, bilateral, stage to stage, principles to skills. 5.3.7 - Practice Types Types: distributed, massed, fixed, variable, mental practice. 5.3.8 - Presentation Types Whole, whole-part-whole, progressive part, part methods. 5.3.9 - Teaching Styles Spectrum Styles: command, reciprocal, problem-solving. 6.1 - Statistical Analysis 6.1.1 - Error Bars Graphically represent variability in data. 6.1.2 - Mean and Standard Deviation Calculation Students should calculate using calculators or spreadsheets. 6.1.3 - Standard Deviation Significance Summarizes spread of data. 68% values within ±1 SD; 95% within ±2 SD in normal distribution. 6.1.4 - Standard Deviation in Data Comparison Small SD implies tightly grouped data, large SD suggests wider spread. 6.1.5 - Coefficient of Variation Ratio of SD to mean, expressed as a percentage. 6.1.6 - T-Test Application Used to compare means, with different forms (paired/unpaired). 6.1.7 - Correlation vs. Causation Correlation doesn't imply one variable causes changes in another. 6.2 - Study Design 6.2.1 - Importance of Fitness Test Validity Specificity : Test relevance to the sport. Accuracy : Close to true measurement. Reliability : Consistency across multiple trials. Validity : Accurate measurement of intended fitness components. 6.2.2 - Study Design Importance Proper design proves causality through control groups and methods. 6.2.3 - PAR-Q Importance Assesses readiness for a general training program. 6.2.4 - Test Evaluation Evaluate field, lab, submaximal, maximal tests, comparing advantages and disadvantages. 6.3 - Components of Fitness Health-related: body composition, cardiorespiratory fitness, flexibility, endurance, strength. Performance-related: agility, balance, coordination, power, reaction time, speed. 6.3.2 - Major Components of Fitness Defined and sport examples provided for each fitness component. 6.3.3 - Fitness Tests Evaluation Evaluate various tests on validity, reliability, and limitations for different fitness components (cardiovascular capacity, flexibility, endurance, agility, etc.). 6.4 - Principles of Training 6.4.1 - General Training Program Elements Warm-up, endurance training, cool-down, flexibility, resistance training, recreational activities. 6.4.2 - Key Principles of Training Design Progressive Overload : Incrementally increase exercise load. Specificity : Tailoring training to specific performance aspects. Reversibility : Fitness loss occurs when training stops. Periodisation : Structuring training year into phases. Variety : Include diverse activities to maintain engagement. 6.4.3 - Monitoring Exercise Intensity Methods: heart rate measurement, Karvonen method, Rating of Perceived Exertion (Borg Scale). Knowt Play Call Kai