2024 IB DP Sports, Exercise and Health Science Practice Paper with Answers

During muscle contraction, the sliding filament theory states that actin (thin) filaments slide past myosin (thick) filaments. As the actin filaments slide toward the center of the sarcomere, the H-zone (which contains only thick filaments) narrows or completely disappears, thus shortening. The A-band, which represents the full length of the thick myosin filaments, remains unchanged in length.

Award 1 mark for the correct answer A. No other options are correct.

In a first-class lever system, the fulcrum (pivot point) is located between the effort (force applied) and the resistance (load). During extension of the elbow joint (such as in a triceps pushdown), the elbow joint acts as the fulcrum, the triceps muscle contraction provides the effort posterior to the joint, and the forearm/external resistance acts as the load anterior to the joint. This configuration corresponds to Effort-Fulcrum-Load (first-class lever).

Award 1 mark for the correct answer B. Option A is a third-class lever. Option C is a second-class lever. Option D is a third-class lever.

Once the shot put is released and is in mid-flight, there is no longer physical contact with the athlete. Therefore, the force from the thrower's hand is zero. In the absence of air resistance, the only force acting on the projectile is the gravitational force pulling it downwards. Inertia is a property of matter (mass), not an active force.

Award 1 mark for the correct answer B.

Upon initiating sub-maximal steady-state exercise, heart rate increases to meet metabolic demands. Stroke volume also increases due to enhanced venous return (Frank-Starling mechanism) and increased myocardial contractility, but it reaches a plateau (usually at 40-60% of \(VO_2\) max). Therefore, stroke volume increases up to a plateau, while heart rate stabilizes at a elevated steady-state level.

Award 1 mark for the correct answer B.

The ATP-CP (adenosine triphosphate-creatine phosphate) system, or phosphagen system, provides energy anaerobically at a high rate but has a very limited capacity. It is the dominant energy pathway for short-duration, high-intensity explosive activities lasting under 10-15 seconds.

Award 1 mark for the correct answer C.

In human nutrition, carbohydrates yield approximately \(17\text{ kJ}\cdot\text{g}^{-1}\) of energy, while lipids (fats) yield approximately \(37\text{ kJ}\cdot\text{g}^{-1}\) of energy. Protein yields approximately \(17.2\text{ kJ}\cdot\text{g}^{-1}\).

Award 1 mark for the correct answer D.

Feedback about the specific kinematics or movement characteristics of a skill (how the movement was executed, e.g., 'your hips were too low') is classified as Knowledge of Performance (KP). Because the information is delivered by an external source (the coach), it is classified as extrinsic feedback.

Award 1 mark for the correct answer B.

Bandura proposed four primary sources of self-efficacy: performance accomplishments (past mastery experiences), vicarious experiences (modeling), verbal persuasion, and physiological/emotional states. Among these, performance accomplishments (having personally successfully executed the behavior in the past) are considered the most powerful and reliable source of self-efficacy.

Award 1 mark for the correct answer D.

During the lowering (eccentric) phase of a squat, gravity acts to flex the knees and hips. To control this movement and prevent falling, the quadriceps muscle group must contract while lengthening. This lengthening of muscle fibers under tension is defined as an eccentric contraction.

Award 1 mark for identifying option B (eccentric) as the correct type of muscle contraction. No marks are awarded for concentric (shortening under tension), isometric (tension with no change in length), or isokinetic (tension at a constant angular velocity).

In a biceps curl, the elbow joint serves as the fulcrum (F). The insertion of the biceps brachii tendon on the radius represents the point of effort (E), which lies between the joint (F) and the dumbbell in the hand, representing the load or resistance (R). A lever system where the effort is located between the fulcrum and the resistance is classified as a third-class lever.

Award 1 mark for identifying option C (Third class lever) as the correct answer. No marks are awarded for first, second, or non-existent fourth-class levers.

Cardiovascular drift refers to the progressive increase in heart rate and decrease in stroke volume during prolonged exercise. In a warm environment, sweat loss reduces plasma volume and blood viscosity increases. This reduces venous return and stroke volume. To maintain cardiac output (\(Q = HR \times SV\)), the heart rate must increase.

Award 1 mark for selecting option B, which correctly describes the relationship between sweating, plasma volume reduction, stroke volume decrease, and compensatory heart rate increase. Other options describe opposite or incorrect physiological processes.

To maximize muscle glycogen resynthesis immediately after exercise, high glycemic index (GI) carbohydrates are preferred because they are rapidly digested and absorbed, causing a swift spike in blood glucose and insulin. This insulin response facilitates rapid glucose uptake into muscle cells via GLUT4 transporters. White bread has a high glycemic index, unlike oatmeal, peanut butter, or broccoli.

Award 1 mark for option B. High GI carbohydrates are recommended immediately post-exercise. Low GI foods (oatmeal, peanut butter, broccoli) do not stimulate insulin and glucose uptake as rapidly.

The feedback is delivered after the movement has been completed, making it terminal (rather than concurrent, which occurs during the action). The feedback focuses on the technical execution and movement pattern (hand entry angle) rather than the outcome (e.g., race time), making it knowledge of performance (KP) rather than knowledge of results (KR).

Award 1 mark for option C. Terminal feedback is provided after the event; knowledge of performance focuses on the mechanics/technique of the movement.

The Inverted-U hypothesis suggests there is an optimal level of arousal for performance. For complex skills or novice athletes, the optimal level of arousal is lower. High arousal can narrow attention too much or cause muscle tension, degrading fine control and decision-making required for complex tasks and less experienced performers.

Award 1 mark for option B. Novices and complex tasks require lower levels of arousal for peak performance compared to simple tasks or elite athletes.

Intrinsic motivation refers to participating in an activity for the inherent satisfaction, fun, or challenge of the activity itself, rather than for some separable outcome or external reward. Enjoying skill mastery and self-improvement are classic indicators of intrinsic motivation.

Award 1 mark for option C. Intrinsic motivation is characterized by internal drives such as enjoyment, personal satisfaction, and mastery.

The SMARTER acronym stands for Specific, Measurable, Achievable/Action-oriented, Realistic, Time-phased, Exciting, Recorded (or evaluated). The inclusion of specific numeric times ('11.5 seconds to 11.2 seconds') allows the progress to be precisely quantified and measured, representing the 'Measurable' component.

Award 1 mark for option B. Measurable refers to the quantitative aspect of the goal that allows progress to be tracked objectively.

During the upward phase of a wide-grip pull-up, the body is pulled upward toward the bar. The arms move from an abducted position toward the trunk, which is shoulder adduction. This movement occurs in the frontal plane around an anteroposterior axis.

Award 1 mark for the correct answer (B). No partial marks are awarded.

With top-spin, the upper surface of the ball rotates against the oncoming airflow, slowing the air velocity on top. According to Bernoulli's principle, lower velocity results in higher pressure. The bottom surface rotates with the airflow, increasing velocity and lowering pressure. This pressure differential (high pressure on top, low pressure below) pushes the ball downwards.

Award 1 mark for the correct answer (B). No partial marks are awarded.

In untrained individuals, stroke volume increases during progressive exercise but typically plateaus at approximately 40% to 60% of \(VO_2\max\). In contrast, heart rate increases linearly with exercise intensity up to its maximum.

Award 1 mark for the correct answer (A). No partial marks are awarded.

The immediate increase in ventilation at the onset of exercise (Phase I) is driven by neural mechanisms, including motor cortex feed-forward signals (anticipatory rise) and sensory feedback from proprioceptors (mechanoreceptors) in the moving joints and muscles. Chemical (humoral) changes in the blood take longer to develop.

Award 1 mark for the correct answer (C). No partial marks are awarded.

Carbohydrates require less oxygen to metabolize and produce a given amount of ATP compared to lipids (making them more oxygen-efficient, yielding approximately 5.05 kcal per liter of \(O_2\) versus approximately 4.69 kcal for lipids). Lipids are more energy-dense per gram, but less efficient in terms of oxygen consumption.

Award 1 mark for the correct answer (B). No partial marks are awarded.

A goalkeeper saving a penalty is an open skill because the environment is unpredictable (dependent on the opponent's kick direction). It is a discrete skill because it has a clear beginning and end. It is a gross motor skill because it requires large muscle groups to execute the dive.

Award 1 mark for the correct answer (C). No partial marks are awarded.

Schmidt's schema theory states that after a movement, four sources of information are briefly stored: (1) Initial conditions (e.g., body position), (2) Response specifications (parameters of the motor program), (3) Sensory consequences (how it felt, looked, sounded), and (4) Response outcomes (the actual result, or knowledge of results).

Award 1 mark for the correct answer (B). No partial marks are awarded.

During a standing calf raise, the metatarsophalangeal joints (ball of the foot) act as the fulcrum (axis). The load (body weight) acts downwards through the talus (middle). The effort is applied by the gastrocnemius and soleus muscles pulling upwards on the calcaneus via the Achilles tendon. Since the load is in the middle, it is a second-class lever.

Award 1 mark for the correct answer (B). No partial marks are awarded.

During the upward phase of a push-up, the elbow joint extends. Elbow extension is driven by the agonist muscle, the triceps brachii, contracting concentrically (shortening under tension) to overcome gravity.

Award 1 mark for the correct option (A). No partial marks.

A second-class lever has the load situated between the fulcrum and the effort. In plantar flexion (standing on toes), the fulcrum is the metatarsophalangeal joint, the load is the body weight passing through the ankle, and the effort is applied by the gastrocnemius/soleus muscles via the Achilles tendon.

Award 1 mark for the correct option (C). No partial marks.

At the absolute onset of exercise, the rapid increase in heart rate is primarily due to the withdrawal of parasympathetic (vagal) tone. Sympathetic stimulation and chemical/hormonal changes occur shortly thereafter but are slower to act.

Award 1 mark for the correct option (A). No partial marks.

Glycolysis is the anaerobic metabolic pathway occurring in the cytoplasm that breaks down one molecule of glucose into two molecules of pyruvate, yielding a net of 2 ATP.

Award 1 mark for the correct option (B). No partial marks.

Proprioceptive feedback comes from within the body (sensory receptors in muscles/joints), making it intrinsic. Since the adjustment is made mid-swing (during the execution of the skill), it is concurrent feedback.

Award 1 mark for the correct option (B). No partial marks.

Mesomorphs are characterized by a muscular, athletic build with low body fat, broad shoulders, and narrow hips.

Award 1 mark for the correct option (C). No partial marks.

Patellar tendinopathy (jumper's knee) is caused by repetitive stress and microtrauma to the patellar tendon over time, classifying it as a chronic overuse injury. The other options are acute injuries caused by sudden trauma.

Award 1 mark for the correct option (A). No partial marks.

Self-Determination Theory states that individuals have three innate psychological needs: autonomy (feeling in control of one's actions), competence (feeling effective), and relatedness (feeling connected to others).

Award 1 mark for the correct option (A). No partial marks.

The radiocarpal joint (wrist) is a condyloid joint, which is a type of biaxial joint. Biaxial joints allow movement in two planes (flexion/extension and abduction/adduction/radial/ulnar deviation). The humeroulnar joint is a hinge joint (uniaxial), the glenohumeral joint is a ball-and-socket joint (multiaxial), and the atlantoaxial joint is a pivot joint (uniaxial).

Award 1 mark for the correct option (B).

In a third-class lever, the effort force is located between the fulcrum and the load. During a biceps curl, the elbow joint acts as the fulcrum, the biceps muscle inserts between the elbow and the hand to provide the effort, and the weight in the hand acts as the load. This is a classic third-class lever system.

Award 1 mark for the correct option (C).

During dynamic, submaximal aerobic exercise, systolic blood pressure increases in response to the increased cardiac output. Diastolic blood pressure, however, remains relatively constant or decreases slightly due to vasodilation of the blood vessels supplying the active skeletal muscles, which minimizes resistance to blood flow.

Award 1 mark for the correct option (B).

Saturated fatty acids have no double bonds between carbon atoms in their hydrocarbon chain; they are 'saturated' with hydrogen atoms. Unsaturated fatty acids contain one (monounsaturated) or more (polyunsaturated) double bonds, which introduces kinks in the carbon chain.

Award 1 mark for the correct option (B).

The feedback is provided by an external source (the coach), making it extrinsic (augmented) feedback. It describes the technique and execution of the movement (the open racket face during contact) rather than the outcome of the shot, which makes it knowledge of performance.

Award 1 mark for the correct option (B).

Sheldon's somatotypes classify body types into three categories: endomorph, mesomorph, and ectomorph. An ectomorph is characterized by a linear, thin, and fragile build with narrow shoulders, narrow hips, and very low body fat. Mesomorphs are muscular and athletic, while endomorphs have higher body fat and a rounder shape.

Award 1 mark for the correct option (C).

Dendrites are the branched projections of a neuron that act to conduct the electrochemical stimulation received from other neural cells to the cell body (soma). The axon transmits signals away from the cell body, the myelin sheath insulates the axon, and the Nodes of Ranvier allow for saltatory conduction.

Award 1 mark for the correct option (C).

Process goals focus on the actions and behaviors an individual must engage in during performance to execute a skill effectively (such as focusing on technique or biomechanics). Performance goals focus on achieving standards or performance objectives independent of other competitors (e.g., achieving a specific personal best time). Outcome goals focus on competitive results (e.g., winning a race).

Award 1 mark for the correct option (C).

Relationship:
- As the carbohydrate concentration of the solution increases, the gastric emptying rate decreases (particularly when exceeding 4% to 8%).

Physiological Mechanism:
- Solutions with higher carbohydrate concentrations have higher osmolarity/osmolality.
- High-osmolarity solutions entering the duodenum are detected by duodenal osmoreceptors.
- This triggers a negative feedback loop (via hormones like GIP/cholecystokinin or neural pathways like the enterogastric reflex) that slows gastric emptying to prevent overloading the small intestine and to optimize nutrient absorption.

Award [1] for stating the correct relationship.
Award [1] for linking higher carbohydrate concentration to increased osmolarity / osmotic pressure.
Award [1] for explaining that this triggers osmoreceptors / hormonal feedback to slow gastric emptying.
[Max 3 marks]

Lever class: Second-class lever.

Lever components in plantarflexion:
- Fulcrum: Located at the ball of the foot / metatarsophalangeal joints.
- Load: Located at the ankle joint / talus (representing the downward line of gravity/body weight).
- Effort: Provided by the contraction of the calf muscles (gastrocnemius and soleus) pulling upward on the calcaneus via the Achilles tendon.

Award [1] for identifying the correct lever class (second-class lever).
Award [1] for correctly locating the fulcrum and load.
Award [1] for correctly locating the effort.
[Max 3 marks]

1. Rotation and Airflow: Topspin causes the upper surface of the ball to rotate forward (against the oncoming airflow), while the lower surface rotates backward (in the direction of the oncoming airflow).
2. Boundary Layer and Velocity: This rotation slows down the air velocity over the top of the ball and increases the air velocity under the bottom of the ball.
3. Pressure Differential and Force: According to Bernoulli's principle, this velocity difference creates a high-pressure zone on top of the ball and a low-pressure zone beneath it. This pressure gradient generates a downward force (Magnus force), causing the ball to dip or drop much faster than it would under the influence of gravity alone.

Award [1] for explaining how rotation alters airflow velocity on the top versus the bottom of the ball.
Award [1] for explaining how the velocity difference creates a pressure differential (high pressure on top, low pressure below).
Award [1] for identifying that this pressure difference produces a downward force (Magnus force) that alters the flight path downward.
[Max 3 marks]

- Frontal Surface Area: A larger cross-sectional area facing the oncoming wind increases air resistance/drag. Lowering the body reduces this area.
- Velocity / Speed: Aerodynamic drag increases exponentially with the square of the velocity (\(F_d \propto v^2\)). Thus, drag becomes significantly greater at higher speeds.
- Shape and Streamlining / Surface Texture: The aerodynamic shape of the helmet, bicycle frame, and the texture of the cyclist's clothing (e.g., smooth skin suits) influence the separation of the boundary layer of air, thereby affecting drag.

Award [1] for each distinct factor outlined:
- Frontal surface area [1]
- Velocity of the cyclist [1]
- Shape/Streamlining of equipment or surface texture of clothing [1]
[Max 3 marks]

- Initial response: Both untrained and highly trained individuals show an initial rapid increase in stroke volume as intensity increases from rest to submaximal levels.
- Plateau in untrained: In untrained individuals, stroke volume reaches a plateau at approximately 40-50% of \(VO_2\text{max}\) (and does not increase further at higher workloads).
- Continuous increase in trained: In highly trained endurance athletes, stroke volume does not plateau early but continues to rise steadily up to maximal or near-maximal workloads due to enhanced ventricular compliance, myocardial contractility, and increased blood volume.

Award [1] for noting the shared initial increase from rest to low/moderate intensity.
Award [1] for stating that untrained individuals plateau at around 40-50% of peak aerobic capacity.
Award [1] for stating that trained endurance athletes can continue to increase stroke volume up to near-maximal intensities (or plateau at much higher workloads).
[Max 3 marks]

- Definition: The oxygen deficit is the difference between the total oxygen required to perform a specific workload and the actual volume of oxygen consumed at the onset of that exercise.
- Cause / Lag: At the start of exercise, the cardiorespiratory and muscular systems do not immediately match the increased demand for oxygen (lag in oxygen uptake kinetics).
- Energy Compensation: Because oxygen delivery is insufficient to meet energy demands aerobically during this transition phase, anaerobic pathways (specifically the ATP-PC system and anaerobic glycolysis) must supply the required ATP.

Award [1] for defining the oxygen deficit as the gap between oxygen demand and actual oxygen consumption.
Award [1] for identifying the cause as a physiological lag in the cardiorespiratory response at the start of exercise.
Award [1] for explaining that anaerobic systems (ATP-PC/glycolysis) must temporarily supply the ATP during this period.
[Max 3 marks]

- Intrinsic Feedback: Information received by the athlete's own internal sensory systems (proprioception, vision, vestibular system, and touch) as a direct consequence of performing the movement.
- Example: A basketball player feeling that the ball left their fingertips poorly or seeing the ball miss the hoop.
- Extrinsic Feedback: Information provided to the athlete by an external source (e.g., a coach, video replay, stopwatch, or heart rate monitor) that supplements their intrinsic feedback.
- Example: A track coach telling a sprinter their reaction time out of the blocks was 0.15 seconds.

Award [1] for distinguishing intrinsic feedback as internal/sensory based.
Award [1] for distinguishing extrinsic feedback as external/supplementary.
Award [1] for providing correct sporting examples for both types of feedback.
[Max 3 marks]

- Genetic Limit / Ceiling: Genetics determine the upper boundary or potential limit of an individual's \(VO_2\text{max}\) (e.g., via inherited traits like heart size, maximum stroke volume, and percentage of slow-twitch type I muscle fibers).
- Environmental Influence: Environmental factors (primarily aerobic endurance training, physical activity levels, and altitude exposure) stimulate physiological adaptations that raise \(VO_2\text{max}\) within that genetically determined range.
- Interaction: An individual with high genetic potential will not reach high aerobic levels without the appropriate training environment, whereas someone with a low genetic ceiling may maximize their potential through training but still fall short of elite levels.

Award [1] for explaining that genetics set the baseline/upper limit (ceiling) of potential \(VO_2\text{max}\).
Award [1] for explaining that environmental factors (training/altitude) stimulate adaptations to reach that potential.
Award [1] for explaining the interaction (e.g., training is required to express genetic potential, but genetics ultimately limit the maximum possible improvement).
[Max 3 marks]

During prolonged exercise, the rate of gastric emptying is influenced by the nutrient concentration of the ingested fluid. Solutions with a high carbohydrate concentration (typically greater than 6% to 8%) have high osmolarity. When these hypertonic solutions enter the small intestine, they stimulate osmoreceptors, which send inhibitory feedback to the stomach to slow down emptying. This delay helps regulate nutrient absorption but can reduce the rate of fluid delivery to the active tissues and increase the risk of bloating and gastrointestinal discomfort.

Award [1] for stating that higher carbohydrate concentrations (above 6-8%) slow down the rate of gastric emptying. Award [1] for explaining that this is due to increased osmolarity of the solution activating osmoreceptors in the small intestine. Award [1] for linking this delay to a physiological consequence, such as slower fluid delivery or increased risk of gastrointestinal discomfort.

At rest, blood is distributed evenly to meet baseline metabolic demands, with significant flow to kidneys and digestive organs. During sub-maximal exercise, the sympathetic nervous system triggers vasodilation in the arterioles supplying active skeletal muscles to meet their increased oxygen demand. Simultaneously, vasoconstriction occurs in arterioles supplying non-essential organs like the kidneys, stomach, and intestines, redirecting blood where it is needed most.

Award [1] for identifying vasodilation in arterioles supplying active skeletal muscles. Award [1] for identifying vasoconstriction in arterioles supplying non-essential visceral organs (such as the kidneys or digestive tract). Award [1] for stating that this redistribution is regulated by the sympathetic nervous system or local chemical changes (such as oxygen tension, pH, or carbon dioxide levels).

The coefficient of friction is a dimensionless scalar value representing the ratio of the force of friction between two bodies to the normal force pressing them together, represented by the formula \(\mu = F_f / F_R\). At the start of a 100m race, the sprinter uses spiked athletic shoes to significantly increase the coefficient of friction between the shoes and the running track. This allows them to exert a massive horizontal propulsive force against the starting blocks and track surface without slipping, ensuring maximum acceleration.

Award [1] for defining the coefficient of friction as the ratio of frictional force to the normal force pressing two surfaces together. Award [1] for explaining that specialized footwear (spikes) increases the coefficient of friction between the foot and the track surface. Award [1] for explaining that this increased friction prevents slipping and allows the sprinter to maximize horizontal force application during the initial acceleration phase.

Skeletal muscle contraction relies on both chemical and mechanical processes. Calcium ions (\(Ca^{2+}\)) are released from the sarcoplasmic reticulum and bind to troponin, which shifts tropomyosin to expose the active binding sites on actin. Adenosine triphosphate (ATP) plays a dual role: its binding to the myosin head causes it to detach from actin, and its subsequent hydrolysis into ADP and inorganic phosphate provides the energy to 're-cock' the myosin head, preparing it for the next cross-bridge cycle and power stroke.

Award [1] for outlining that calcium ions bind to troponin, causing a conformational change in tropomyosin that exposes myosin-binding sites on actin. Award [1] for stating that ATP binding to the myosin head causes it to detach from the actin filament. Award [1] for stating that the hydrolysis of ATP provides the energy required to cock/energize the myosin head for the next contraction cycle.

In sports performance, timing components are distinct but related. Reaction time is the elapsed time between the presentation of a stimulus (the kicker striking the ball) and the initiation of the physical response (the goalkeeper starting to move). Movement time is the time taken from the initiation of that movement to its completion (the goalkeeper reaching the path of the ball). Response time is the total integrated duration, which is mathematically expressed as response time equals reaction time plus movement time.

Award [1] for defining reaction time as the interval from the onset of the stimulus to the initiation of the movement response. Award [1] for defining movement time as the duration from the start of the physical movement to its final completion. Award [1] for stating that response time is the sum of reaction time and movement time.

Type I muscle fibers are specialized for aerobic metabolism, which is essential for endurance performance. Structurally, they have a high density of capillaries and high concentrations of myoglobin, facilitating efficient oxygen transport and delivery from blood into the cells. Metabolically, they are packed with a high density of mitochondria and high levels of oxidative enzymes, enabling them to generate large amounts of ATP via aerobic pathways. These combined characteristics make Type I fibers highly resistant to fatigue over extended periods of exercise.

Award [1] for explaining that high capillary density and myoglobin content facilitate continuous oxygen delivery and transport to the cells. Award [1] for explaining that high mitochondrial density and aerobic/oxidative enzymes enable efficient ATP production through aerobic pathways. Award [1] for linking these structural and metabolic characteristics to high fatigue resistance, which is necessary for sustained endurance performance.

The sudden increase in ventilation at the very start of exercise occurs too rapidly to be caused by changes in blood chemistry (like arterial blood gas levels). Instead, it is regulated by neural mechanisms. First, central command from the cerebral cortex simultaneously stimulates the motor cortex to initiate muscle contraction and the respiratory center in the medulla oblongata to increase breathing. Second, proprioceptors (mechanoreceptors) in active muscles and joints immediately send afferent feedback to the brainstem, signaling that physical movement has commenced and prompting a rapid increase in both tidal volume and breathing rate.

Award [1] for stating that this initial rapid increase is regulated by neural/neurogenic mechanisms rather than chemical changes in the blood. Award [1] for explaining that central command from the cerebral cortex sends motor impulses that simultaneously stimulate active muscles and the respiratory control center. Award [1] for explaining that proprioceptors in moving joints and skeletal muscles send sensory feedback to the respiratory center to immediately increase ventilation.

The trajectory and horizontal displacement of any airborne projectile are dictated by three key biomechanical parameters: the speed of release, the angle of release, and the height of release. An athlete can actively manipulate these variables to optimize performance. For example, a shot putter or javelin thrower can focus on maximizing the speed of release (the most critical factor) by executing a faster approach run-up and explosive final extension, thereby transferring greater kinetic energy into the implement to increase its flight distance.

Award [1] for identifying all three factors: speed of release, angle of release, and height of release. Award [1] for choosing one factor and explaining how an athlete can physically manipulate it (e.g., using a faster run-up to increase speed of release, adjusting release angle to around 35-45 degrees, or extending the body at release to maximize release height). Award [1] for explaining how this manipulation directly improves the flight path or horizontal displacement of the projectile.

1. During landing, the knee undergoes flexion to absorb force. 2. The quadriceps (agonist muscle group) contract eccentrically, meaning they lengthen while generating tension to control the rate of knee flexion and decelerate the body. 3. Simultaneously, reciprocal inhibition occurs where the central nervous system sends an inhibitory signal to the antagonist muscle group (the hamstrings). 4. This causes the hamstrings to relax, preventing them from resisting the knee flexion. 5. The coordination between eccentric contraction and reciprocal inhibition prevents injury, provides stability, and ensures a controlled, smooth deceleration.

Award [1] mark for each of the following, up to [5]: - Identifies that knee flexion occurs to absorb forces upon landing [1]. - Defines/explains eccentric contraction of the quadriceps (agonist) as lengthening under tension [1]. - Explains that this eccentric action decelerates the descent and absorbs kinetic energy [1]. - Defines reciprocal inhibition as the process where the nervous system inhibits the antagonist while the agonist contracts [1]. - Identifies the hamstrings as the antagonist that must relax to allow knee flexion [1]. - Explains how this co-action prevents injury or ensures smooth movement [1].

1. When a tennis ball has topspin, it rotates forward around its horizontal axis. 2. This rotation drags a boundary layer of air around the ball. 3. On top of the ball, the rotational surface moves against the oncoming airflow, slowing down the air velocity. 4. According to Bernoulli’s principle, slower air velocity creates a region of higher pressure on top of the ball. 5. Underneath the ball, the rotational surface moves in the same direction as the oncoming airflow, increasing the air velocity, which creates a region of lower pressure. 6. This pressure differential (high pressure on top, low pressure below) generates a downward force (Magnus force), causing the ball to dip or drop more rapidly than it would under gravity alone.

Award [1] mark for each of the following, up to [5]: - Recognizes that topspin involves the ball rotating forward around its horizontal axis [1]. - Explains that the rotation drags a boundary layer of air around the ball [1]. - Connects the air velocity on top (slower/opposed) with high pressure according to Bernoulli's principle [1]. - Connects the air velocity underneath (faster/assisted) with low pressure according to Bernoulli's principle [1]. - States that the pressure differential creates a downward force (Magnus force) [1]. - Explains the effect on the flight path (causing the ball to dip/drop quickly) [1].

1. The Fosbury Flop involves the athlete arching their back over the crossbar while facing upwards. 2. By arching the body, the athlete's mass is distributed such that their center of mass (the point at which the body's mass is balanced) actually lies outside of the physical body. 3. As they clear the bar, their center of mass can pass underneath or directly through the crossbar, even though every individual body part passes over it successively. 4. This is highly advantageous because it requires less mechanical work and a lower vertical takeoff velocity compared to techniques where the center of mass must pass above the bar (like the straddle technique). 5. Consequently, the athlete can clear a higher bar with the same amount of vertical force produced at takeoff.

Award [1] mark for each of the following, up to [5]: - Describes the posture of the Fosbury Flop (arching back over the bar facing upwards) [1]. - Defines or explains the center of mass as the point around which body mass is equally distributed [1]. - Explains that arching the back shifts the center of mass outside/below the physical body [1]. - Explicitly states that the center of mass can pass below or through the bar while the body parts clear it [1]. - Connects this phenomenon to a reduced requirement for vertical takeoff velocity/kinetic energy to clear a given height [1]. - Compares this efficiency to other techniques where the center of mass must rise above the bar [1].

1. Cardiovascular drift occurs during prolonged, steady-state exercise (typically after 10 to 20 minutes) in warm conditions. 2. Sweating increases to dissipate heat via evaporation, which leads to a loss of body water and a subsequent reduction in blood plasma volume. 3. A reduction in blood plasma volume decreases venous return (the amount of blood returning to the heart) and end-diastolic volume. 4. This decrease in ventricular filling causes a reduction in stroke volume (the volume of blood pumped per beat). 5. To maintain a constant cardiac output, the heart rate must progressively increase. 6. Additionally, vasodilation of cutaneous blood vessels diverts blood to the skin to facilitate cooling, further reducing central blood volume and stroke volume.

Award [1] mark for each of the following, up to [5]: - Defines cardiovascular drift as a progressive decrease in stroke volume and a progressive increase in heart rate during prolonged, steady-state exercise [1]. - Explains that sweating leads to dehydration / loss of blood plasma volume [1]. - Explains that reduced plasma volume decreases venous return / end-diastolic volume [1]. - Explains that reduced venous return directly lowers stroke volume [1]. - Identifies that heart rate must increase to maintain cardiac output [1]. - Mentions that cutaneous vasodilation (blood flow to the skin for cooling) further reduces venous return [1].

1. Inhalation is an active process initiated by the contraction of respiratory muscles. 2. The diaphragm contracts and moves downwards (flattens), while the external intercostal muscles contract, lifting the ribcage upwards and outwards. 3. These muscular actions increase the physical volume of the thoracic cavity. 4. According to Boyle’s Law, an increase in volume leads to a decrease in pressure; thus, the intrapulmonary (alveolar) pressure drops below atmospheric pressure. 5. This creates a pressure gradient between the external environment and the lungs. 6. Air naturally flows down this pressure gradient (from high pressure outside to low pressure inside) through the respiratory tract into the alveoli until pressures equalize.

Award [1] mark for each of the following, up to [5]: - Identifies inhalation as an active process involving muscle contraction [1]. - States that the diaphragm contracts (moves down/flattens) and external intercostals contract (ribcage moves up/out) [1]. - Explains that these movements increase the volume of the thoracic cavity [1]. - Explains that an increase in thoracic volume decreases the intrapulmonary/alveolar pressure (Boyle's law) [1]. - States that intrapulmonary pressure becomes lower than atmospheric pressure [1]. - Explains that air moves from an area of higher pressure (atmosphere) to lower pressure (lungs) down a pressure gradient [1].

1. Dehydration leads to a reduction in blood plasma volume, which decreases venous return and stroke volume. 2. To compensate, heart rate increases, but overall maximum cardiac output may decrease, limiting oxygen delivery to active muscles and reducing aerobic capacity. 3. Dehydration impairs the body's thermoregulatory capacity; less blood is directed to the skin, and sweat rate decreases, leading to a rise in core body temperature. 4. Elevated core temperature increases the rate of muscle glycogen utilization, hastening the onset of fatigue. 5. High core temperatures and reduced circulation also cause central nervous system fatigue, impairing concentration, decision-making, and perceived exertion (making exercise feel harder).

Award [1] mark for each of the following, up to [5]: - States that dehydration decreases blood plasma volume, reducing venous return and stroke volume [1]. - Explains that reduced oxygen delivery to working muscles impairs aerobic capacity [1]. - Explains that dehydration impairs thermoregulation by reducing sweat rate / skin blood flow [1]. - Connects impaired thermoregulation to an elevated core body temperature [1]. - Explains that elevated core temperature increases reliance on glycogen stores / rate of glycogen depletion [1]. - Mentions that dehydration increases rating of perceived exertion (RPE) or causes cognitive/CNS fatigue [1].

1. Schmidt’s schema theory suggests that motor programs are not stored as specific movements, but as generalized motor programs (GMPs) that can be adapted based on schemas (rules). 2. When preparing a shot, the player uses the recall schema, which consists of initial conditions (information about body position and distance from the basket) and response specifications (the parameters chosen for the movement, such as how much force to apply). 3. During and after the shot, the player uses the recognition schema, which consists of sensory consequences (proprioceptive feedback and visual feedback of the shot while it is occurring) and response outcomes (the actual success of the shot, e.g., did it go in?). 4. If a shot from a new distance is required, the player adjusts the parameters of the GMP using the recall schema based on past experiences. 5. The difference between the actual outcome and the expected outcome is used to update the schemas, improving the accuracy of future movements.

Award [1] mark for each of the following, up to [5]: - Explains that Schmidt's theory relies on Generalized Motor Programs (GMPs) rather than individual stored movements [1]. - Identifies the recall schema and its role in generating/initiating the movement [1]. - Explains that the recall schema uses initial conditions (distance, position) and response specifications (force, angle) [1]. - Identifies the recognition schema and its role in evaluating/correcting the movement [1]. - Explains that the recognition schema uses sensory consequences (how it felt/looked) and response outcomes (success/failure) [1]. - Describes how error feedback (difference between actual and expected outcomes) is used to update the schema for future performance [1].

1. According to Eysenck’s personality theory, introverts have a naturally high level of internal cortical arousal, whereas extraverts have a naturally low level of internal cortical arousal. 2. Because of this, extraverts seek out high-arousal environments to reach their optimum arousal level; they tend to prefer team sports, contact sports, or sports with fast-paced, unpredictable situations (such as rugby or basketball). 3. Introverts, already having high internal arousal, seek to avoid excessive external stimulation to prevent over-arousal; they tend to prefer individual, self-paced sports requiring high concentration and fine motor control (such as archery, golf, or long-distance running). 4. In high-pressure situations, extraverts are more likely to perform well because the increased environmental stress and crowd noise raise their arousal toward their optimal performance zone. 5. In contrast, under high pressure, introverts are prone to becoming over-aroused, which can exceed their optimal zone, leading to cognitive anxiety, loss of focus, and a decline in motor performance.

Award [1] mark for each of the following, up to [5]: - Identifies that introverts have naturally high cortical/reticular arousal, while extraverts have naturally low cortical/reticular arousal [1]. - Explains that extraverts seek external stimulation, leading them to prefer team/contact/high-intensity/dynamic sports [1]. - Explains that introverts avoid excessive stimulation, leading them to prefer individual/fine-motor/high-concentration/self-paced sports [1]. - Explains that in high-pressure situations, extraverts can handle or benefit from the increased arousal to reach their optimal performance level [1]. - Explains that in high-pressure situations, introverts can easily become over-aroused, leading to a decline in performance [1].