2024 IB DP Sports, Exercise and Health Science 模擬試題連答案詳解

Hypotonic sports drinks have a lower osmolarity than body fluids, meaning they contain a lower concentration of salt and carbohydrates. This low concentration allows water to be absorbed rapidly into the bloodstream via osmosis, facilitating quick rehydration.

Award [1] mark for identifying the correct drink type (hypotonic). Reject all other options.

While the percentage of cardiac output directed to the brain decreases during exercise (as a larger share goes to active skeletal muscles), the absolute volume of blood delivered to the brain per minute remains relatively stable or increases slightly due to the massive increase in overall cardiac output and arterial blood pressure.

Award [1] mark for identifying that absolute blood flow to the brain increases slightly or remains relatively constant. Reject other options.

An eccentric contraction occurs when a muscle lengthens under tension. During the lowering phase of a squat, the quadriceps femoris muscle group contracts eccentrically to control the speed of knee flexion against the force of gravity.

Award [1] mark for selecting the correct contraction type (eccentric).

Newton's third law of motion states that for every action, there is an equal and opposite reaction. Therefore, if the sprinter exerts a force of \( 800 \text{ N} \) backwards and downwards, the block must exert an equal force of \( 800 \text{ N} \) directed in the exact opposite direction: forwards and upwards.

Award [1] mark for selecting the correct magnitude and direction representing Newton's third law.

Internal imagery involves the athlete visualizing the execution of a skill from their own first-person perspective, mimicking the actual visual and kinesthetic sensations they would experience during performance. External imagery, by contrast, involves viewing oneself from a third-person perspective.

Award [1] mark for identifying internal imagery.

A penalty kick is classified as a closed skill because the environment is stable, predictable, and the performer can initiate the action when ready. It is a discrete skill because it has a clear, distinct beginning and end (the run-up, strike of the ball, and follow-through).

Award [1] mark for identifying the correct classification (closed and discrete).

Self-Determination Theory (SDT) posits that three basic psychological needs must be met to support intrinsic motivation: autonomy (feeling in control of one's actions), competence (feeling capable and effective), and relatedness (feeling connected to and cared for by others).

Award [1] mark for identifying autonomy, competence, and relatedness as the three needs.

Somatic anxiety refers to the physical symptoms of anxiety, such as increased heart rate, muscle tension, and sweating. In contrast, cognitive anxiety relates to the psychological symptoms, such as worry, self-doubt, and negative thoughts.

Award [1] mark for selecting somatic anxiety.

During prolonged steady-state aerobic exercise, dehydration leads to a loss of plasma volume. This reduction in blood volume decreases venous return and, consequently, stroke volume. To maintain cardiac output, heart rate must increase (a phenomenon known as cardiovascular drift). Therefore, dehydration results in decreased stroke volume and increased heart rate.

Award [1] for the correct answer (B). No partial marks are available for this multiple-choice question.

At the onset of submaximal, constant-intensity exercise, ventilation (\(\dot{V}_E\)) increases rapidly (Phase I), driven primarily by neural mechanisms (motor cortex and joint/muscle receptors). This is followed by a slower, gradual rise (Phase II) driven by humoral/chemical factors (such as arterial \(CO_2\) and \(pH\)) until a steady-state plateau is achieved (Phase III) where oxygen demand meets supply.

Award [1] for the correct answer (B).

During the upward phase of a biceps curl, the elbow is flexing. The biceps brachii is the prime mover (agonist) and is shortening under tension (concentrically contracting). The triceps brachii is the opposing muscle (antagonist) and must relax/stretch to allow the movement to occur.

Award [1] for the correct answer (B).

During the flight phase of a jump, no external torque acts on the jumper, meaning angular momentum (\(H\)) is conserved and remains constant. If the jumper extends their arms and legs outwards, they distribute their mass further from the axis of rotation, which increases their moment of inertia (\(I\)). Since \(H = I\omega\) is constant, an increase in \(I\) results in a corresponding decrease in angular velocity (\(\omega\)).

Award [1] for the correct answer (B).

Process goals focus on the specific actions, movements, or execution behaviors that an athlete must perform to execute a skill effectively. In contrast, outcome goals focus on the competitive result, performance goals focus on personal standard comparison (e.g., achieving a personal best time), and subjective goals are non-specific general intentions.

Award [1] for the correct answer (C).

The feedback is provided by an external source (the coach's observation and measurement), making it extrinsic (augmented) feedback. It provides information about the outcome of the action relative to the target goal (the bullseye), which represents Knowledge of Results (KR).

Award [1] for the correct answer (B).

The mesomorph somatotype is characterized by a high proportion of muscle tissue, low body fat, broad shoulders, and a narrow waist, which is highly advantageous for power-based, strength, and explosive sports.

Award [1] for the correct answer (C).

Self-Determination Theory (SDT) developed by Deci and Ryan identifies three basic psychological needs: competence (feeling effective in interactions with the environment), autonomy (feeling like the origin of one's actions), and relatedness (feeling connected to and cared for by others). Satisfaction of these three needs is critical for psychological growth and intrinsic motivation.

Award [1] for the correct answer (A).

During prolonged exercise in a warm environment, sweat loss reduces plasma volume, leading to a decrease in venous return and stroke volume. To maintain the same cardiac output (Cardiac Output = Stroke Volume x Heart Rate), the heart rate must increase. This phenomenon is known as cardiovascular drift.

Award 1 mark for the correct option (B). Reject all other options.

The parasympathetic nervous system predominates at rest and releases acetylcholine via the vagus nerve. Acetylcholine binds to receptors on the sinoatrial (SA) node, hyperpolarizing the cells and decreasing the rate of spontaneous depolarization, which slows the heart rate.

Award 1 mark for the correct option (D). Reject all other options.

In the cross-bridge cycle, muscle contraction is maintained by the continuous attachment and detachment of myosin heads to actin. Detachment of the myosin head is specifically triggered when a new molecule of adenosine triphosphate (ATP) binds to it.

Award 1 mark for the correct option (A). Reject all other options.

A third-class lever is characterized by the effort (force) being located between the fulcrum and the load (resistance). When the biceps brachii flexes the elbow joint, the elbow joint serves as the fulcrum, the biceps inserts on the radius (force) which lies between the joint and the hand/forearm weight (resistance).

Award 1 mark for the correct option (C). Reject all other options.

Kinesthetic imagery involves imagining the physical sensations of performing a movement, such as muscular tension, balance, and joint position. Internal perspective means viewing the performance from within one's own body. Therefore, focusing on physical feelings of muscle tension and balance represents internal kinesthetic imagery.

Award 1 mark for the correct option (B). Reject all other options.

The cognitive stage of learning is the initial phase where the athlete is trying to understand what needs to be done. Performance is characterized by frequent errors, high variability, lack of consistency, and a high demand for cognitive processing/attention to execute the skill.

Award 1 mark for the correct option (C). Reject all other options.

A mesomorph has a muscular build with broad shoulders and a narrow waist. Individuals with a high mesomorphic rating typically excel in strength and power events because of their genetic predisposition to gain muscle tissue.

Award 1 mark for the correct option (C). Reject all other options.

Self-Determination Theory (Deci and Ryan) identifies three basic, universal psychological needs: Autonomy (the need to feel in control of one's own behavior), Competence (the need to experience mastery and feel effective), and Relatedness (the need to feel connected to others). Satisfying these needs is critical for nurturing intrinsic motivation.

Award 1 mark for the correct option (A). Reject all other options.

The complete aerobic respiration of a glucose molecule starts in the cytoplasm with glycolysis, where glucose is broken down into pyruvate. Pyruvate is then transported into the mitochondria where it enters the Krebs cycle (after conversion to acetyl-CoA). Finally, the reduced coenzymes (such as NADH and FADH2) produced in these earlier stages donate electrons to the electron transport chain on the inner mitochondrial membrane to generate a large amount of adenosine triphosphate (ATP). Thus, the correct sequence is Glycolysis, Krebs cycle, and Electron transport chain.

Award [1] for the correct option (A). No partial marks are awarded.

During skeletal muscle contraction, calcium ions released from the sarcoplasmic reticulum bind directly to troponin. This binding causes a conformational change in troponin, which physically pulls tropomyosin away from the active binding sites on the actin filament, allowing the myosin heads to bind and initiate the cross-bridge cycle.

Award [1] for the correct option (C). No partial marks are awarded.

The Fosbury Flop technique allows the athlete to arch their back over the bar. Because of the curved, arched body shape during the peak of the flight, the athlete's center of mass actually lies outside of their body and passes underneath the crossbar, while the physical body parts clear over it. This means the athlete does not need to lift their center of mass as high to clear a given height, resulting in a more efficient jump.

Award [1] for the correct option (B). No partial marks are awarded.

The immediate, rapid rise in ventilation at the onset of exercise (Phase I) occurs too quickly to be caused by chemical changes in the blood, which take time to develop. Instead, this phase is driven by neural mechanisms: feedforward signals (central command) from the cerebral motor cortex and feedback from mechanoreceptors (proprioceptors) in the active muscles and joints.

Award [1] for the correct option (C). No partial marks are awarded.

This feedback provides information about the outcome of the movement (whether the goal of hitting the bullseye was achieved, quantified by the distance from the target center), which is defined as Knowledge of Results (KR). Because it is provided by an external source (the digital display), it is categorized as extrinsic (or augmented) feedback.

Award [1] for the correct option (B). No partial marks are awarded.

Catastrophe Theory predicts that when an athlete has high cognitive anxiety, an increase in physiological arousal beyond the optimal threshold leads to a rapid, catastrophic drop-off in performance. This is in contrast to the inverted-U hypothesis, which predicts a smooth, gradual decline.

Award [1] for the correct option (A). No partial marks are awarded.

1. Calculate total fluid loss by finding the mass difference: \(72.5\text{ kg} - 71.2\text{ kg} = 1.3\text{ kg}\) of mass lost (which equates to \(1.3\text{ L}\) of fluid loss).
2. Account for fluid intake: \(1.3\text{ L} + 0.5\text{ L} = 1.8\text{ L}\) total sweat loss.
3. Divide by exercise duration to find sweat rate: \(1.8\text{ L} / 2\text{ hours} = 0.9\text{ L}\cdot\text{h}^{-1}\).

[1 mark] for calculating the total sweat loss of \(1.8\text{ L}\) (accounting for weight loss and fluid intake).
[0.67 marks] for dividing the total loss by \(2\text{ hours}\) to get the final correct sweat rate of \(0.9\text{ L}\cdot\text{h}^{-1}\).

During incremental exercise, stroke volume initially increases due to enhanced venous return and myocardial contractility (Frank-Starling mechanism). However, in untrained individuals, it plateaus at moderate intensity (around 40% to 60% of \(\text{V}\text{O}_2\text{ max}\)) because high heart rates limit ventricular filling time (diastasis phase of diastole).

[1 mark] for stating that stroke volume increases initially and plateaus at moderate intensity (40% to 60% of \(\text{V}\text{O}_2\text{ max}\)).
[0.67 marks] for explaining that the plateau is due to reduced ventricular filling time at elevated heart rates.

During the lowering phase, gravity pulls the body down, causing the elbow to flex. To control this movement, the triceps brachii (which is an elbow extensor) must lengthen under tension, performing an eccentric contraction. It acts as the key muscle controlling the speed of descent.

[1 mark] for identifying the contraction as eccentric.
[0.67 marks] for identifying its role in controlling elbow flexion / acting as the agonist resisting gravity during descent.

The Fosbury Flop technique involves arching the back over the bar. This positioning redistributes body mass such that the flight path of the athlete's center of mass actually passes below the level of the crossbar, allowing them to clear a higher bar with less vertical lift.

[1 mark] for explaining that the center of mass passes below/underneath the crossbar.
[0.67 marks] for explaining that the extreme arching/back-bend position enables this redistribution of mass.

Cognitive anxiety represents the subjective thoughts of worry and apprehension, which typically remain stable and elevated days before a competition. Somatic anxiety refers to the physical perceptions of autonomic arousal, which remain low until immediately before the competition, where they rise sharply.

[1 mark] for distinguishing the definitions (mental/cognitive vs physiological/somatic anxiety).
[0.67 marks] for outlining the temporal pattern (cognitive remains stable/high; somatic spikes just before start).

Massed practice features continuous practice intervals with little to no rest, while distributed practice interleaves practice with rest periods. For a novice performing a complex, high-intensity gymnastics routine, distributed practice is safer and more effective to prevent physical fatigue and cognitive overload, reducing injury risk.

[1 mark] for defining/distinguishing massed (continuous) vs distributed (interspersed with rest) practice.
[0.67 marks] for selecting distributed practice with the justification of managing fatigue/safety/cognitive overload.

Intrinsic motivation comes from within; the activity itself is the reward (e.g., surfing because of the thrill of the wave). Identified regulation is an autonomous form of extrinsic motivation where the athlete recognizes and accepts the personal utility of a behavior (e.g., lifting weights to prevent injury).

[1 mark] for distinguishing the definitions (inherent enjoyment vs valuing the utility/outcome of the activity).
[0.67 marks] for providing appropriate examples for both.

As the marathon progresses, glycogen stores in the active skeletal muscles and liver become depleted. The body must transition to relying almost exclusively on beta-oxidation of free fatty acids. Because fat oxidation has a higher oxygen cost and a slower rate of ATP resynthesis compared to carbohydrate oxidation, the runner is forced to slow down.

[1 mark] for identifying glycogen depletion as the cause and the subsequent shift to fat metabolism.
[0.67 marks] for explaining that fat metabolism yields ATP at a slower rate / has higher oxygen demand, reducing power output.

A high-GI carbohydrate is rapidly digested and absorbed, causing a sudden rise in blood glucose levels. In response, the pancreas secretes a large amount of insulin to facilitate glucose uptake into cells. During the subsequent exercise, the combination of high insulin levels and muscle contraction-induced glucose uptake causes blood glucose to drop below baseline (rebound hypoglycemia), which can cause dizziness and weakness. Additionally, high insulin levels inhibit lipolysis (the breakdown of fats), forcing the body to rely more heavily on muscle glycogen stores, leading to premature fatigue.

Award 1 mark for identifying the insulin spike and subsequent rebound hypoglycemia. Award 0.67 marks for explaining the inhibition of fat oxidation/increased reliance on glycogen leading to premature fatigue.

During prolonged exercise in a warm environment, the body increases sweat rate to facilitate thermoregulation. This loss of fluid leads to a reduction in blood plasma volume, which decreases venous return to the heart and consequently reduces stroke volume. Since cardiac output \(Q = HR \times SV\) is the product of stroke volume and heart rate, the heart rate must increase progressively over time to maintain the required cardiac output for the exercising muscles.

Award 1 mark for explaining that sweating reduces plasma volume, leading to a decrease in venous return and stroke volume. Award 0.67 marks for linking this to a compensatory increase in heart rate to maintain cardiac output.

A motor unit consists of a single motor neuron and all the muscle fibers it innervates. According to the 'all-or-none' law, when an electrical impulse (action potential) travels down the motor neuron, it must exceed a specific threshold level to trigger a contraction. If the stimulus exceeds this threshold, all the muscle fibers in that unit will contract fully and simultaneously. If the stimulus is even slightly below this threshold, none of the muscle fibers in that motor unit will contract at all. There is no partial contraction of a single motor unit.

Award 1 mark for stating that if the threshold is reached, all muscle fibers within the motor unit contract fully and simultaneously. Award 0.67 marks for clarifying that if the threshold is not reached, no fibers contract (no partial contraction).

When a tennis ball spins, it drags a boundary layer of air around with it. On one side of the ball, this boundary layer moves in the same direction as the oncoming air flow, increasing air velocity and creating a low-pressure zone (according to Bernoulli's principle). On the opposite side, the boundary layer moves against the oncoming air flow, decreasing air velocity and creating a high-pressure zone. The resulting pressure differential generates a force (the Magnus force) directed from the high-pressure side to the low-pressure side, causing the ball to curve away from its normal parabolic flight path.

Award 1 mark for explaining the creation of a pressure differential due to air velocity differences on opposite sides of the spinning ball. Award 0.67 marks for describing how this pressure difference generates a force that deviates the ball from its normal path.

Progressive Muscle Relaxation (PMR) is classified as a somatic relaxation technique because it directly addresses physical symptoms of anxiety. It involves the physical tensing and releasing of major muscle groups to reduce muscle tension and lower overall physical arousal. In contrast, mental imagery is a cognitive anxiety reduction technique that addresses mental worry, doubt, and negative thoughts. It involves the mental rehearsal of successful motor performance or the visualization of peaceful scenes to enhance self-confidence and direct focus away from stressors.

Award 1 mark for distinguishing PMR as a somatic technique focusing on muscle tension/physical relaxation. Award 0.67 marks for distinguishing mental imagery as a cognitive technique focusing on mental focus/reduction of psychological worry.

Concurrent feedback is received by the learner during the actual performance of the motor skill (e.g., a gymnast feeling their body position on a balance beam). This allows for immediate, real-time adjustments to correct errors during the movement. Terminal feedback, on the other hand, is provided after the movement or performance has concluded (e.g., a coach giving feedback on a tennis serve after it has been executed). Terminal feedback is crucial for evaluating the overall outcome of the action and planning modifications for subsequent practice attempts.

Award 1 mark for explaining concurrent feedback as real-time feedback during performance for immediate correction. Award 0.67 marks for explaining terminal feedback as post-performance feedback used for future planning.

In a double-blind study design, neither the participants nor the researchers who interact with them or analyze the data know who is receiving the active nutritional supplement and who is receiving the inactive placebo. This is critical in sports science because: 1) It prevents the placebo effect (participant expectancy), where participants might perform better simply because they believe they took an ergogenic aid. 2) It eliminates researcher/experimenter bias, ensuring that the researchers do not unconsciously influence the participants, alter their testing protocols, or bias their interpretation of performance data.

Award 1 mark for explaining that it prevents participant expectancy/placebo effects. Award 0.67 marks for explaining that it eliminates researcher/experimenter bias in data collection and interpretation.

According to Deci and Ryan's Self-Determination Theory, intrinsic motivation is maximized when three basic psychological needs are satisfied: 1) Autonomy: the need to feel in control of one's own behaviors, decisions, and training directions. 2) Competence: the need to experience mastery and feel effective when interacting with the athletic environment and learning new skills. 3) Relatedness: the need to feel connected to, cared for, and a sense of belonging with teammates, coaches, and the wider sporting community.

Award 0.67 marks for correctly identifying and outlining autonomy. Award 0.5 marks for identifying and outlining competence. Award 0.5 marks for identifying and outlining relatedness. (Total: 1.67 marks)

During submaximal exercise, the body redistributes cardiac output to prioritize the oxygen and nutrient demands of working skeletal muscles. This is achieved through two main mechanisms: 1. Vasoconstriction: Sympathetic nervous system activity increases, causing the smooth muscle in arterioles supplying non-essential organs (such as the kidneys, stomach, and intestines) to constrict, reducing blood flow to these regions. 2. Vasodilation: Local metabolic changes in the active muscles (such as increases in temperature, carbon dioxide, and lactic acid, and decreases in oxygen) trigger the relaxation of arteriolar smooth muscle (autoregulation/vasodilation), dramatically increasing localized blood flow to the active skeletal muscles.

Award [0.83 marks] for explaining vasoconstriction of arterioles supplying non-essential organs (e.g., kidneys, gut) mediated by sympathetic stimulation. Award [0.84 marks] for explaining vasodilation of arterioles supplying active skeletal muscle triggered by local metabolic factors (e.g., increased CO2, decreased O2, heat).

Performance is the temporary, observable execution of a motor skill at a single point in time. It is highly susceptible to transient factors such as fatigue, anxiety, motivation, and environmental conditions. Learning, on the other hand, is a relatively permanent change in the capability to perform a skill, resulting from practice or experience. Learning cannot be directly observed; instead, it must be inferred through sustained improvement, consistency, and retention tests administered after a period of no practice.

Award [0.83 marks] for defining performance as a temporary, fluctuating, or directly observable execution of a skill. Award [0.84 marks] for defining learning as a relatively permanent change in capability that is not directly observable and must be inferred over time/through retention.

1. High-GI carbohydrate foods are digested and absorbed rapidly, leading to a quick and substantial spike in blood glucose levels. 2. This rapid rise in blood glucose triggers a high insulin response from the pancreas. 3. Elevated insulin levels stimulate the translocation of GLUT-4 transporters to cell membranes, facilitating faster glucose uptake by the depleted muscle cells. 4. Consequently, muscle glycogen resynthesis rates are maximized, which is highly beneficial during the short window of opportunity (first 1 to 2 hours post-exercise) for rapid recovery.

Award 1 mark for each of the following: 1. Identifies that high-GI carbohydrates are rapidly digested and absorbed, causing a quick increase in blood glucose. 2. Explains that this causes a high insulin release from the pancreas. 3. Connects elevated insulin levels to increased glucose uptake by muscle cells (accept mention of GLUT-4 transporters). 4. Identifies that this maximizes/accelerates muscle glycogen resynthesis, especially during the early post-exercise recovery window.

1. Dynamic exercise increases cardiac output significantly due to increases in both heart rate and stroke volume, whereas static exercise results in a more moderate increase in cardiac output because stroke volume is limited by high intrathoracic pressures. 2. In dynamic exercise, widespread vasodilation occurs in active muscles, reducing total peripheral resistance, which limits the increase in mean arterial pressure. 3. In static exercise, sustained muscle contractions mechanically compress blood vessels within the contracting muscle bed. 4. This compression causes a sharp increase in total peripheral resistance, leading to a much larger, dramatic surge in mean arterial pressure (both systolic and diastolic).

Award 1 mark for each of the following: 1. Identifies that dynamic exercise causes a larger increase in cardiac output (due to increases in both heart rate and stroke volume) compared to static exercise. 2. Explains that dynamic exercise results in vasodilation in active muscles, lowering peripheral resistance and moderating the rise in mean arterial pressure. 3. Explains that static exercise involves sustained muscle contraction that mechanically compresses blood vessels. 4. Connects this compression to an increase in total peripheral resistance, which causes a disproportionately large increase in mean arterial pressure.

1. Henneman's size principle states that motor units are recruited in an orderly, sequential manner based on the size of their motor neuron cell bodies, from smallest to largest. 2. Under low-force demands, smaller motor units (which typically innervate Type I / slow-twitch muscle fibers) are recruited first because they have low activation thresholds. 3. As the demand for force increases during the progressive contraction, larger motor units (which innervate Type IIa and eventually Type IIx / fast-twitch muscle fibers) are recruited because they have higher activation thresholds. 4. This sequential recruitment allows for smooth transitions and fine control of force production, while preventing the premature fatigue of high-threshold, highly fatigable fast-twitch fibers.

Award 1 mark for each of the following: 1. Outlines that motor units are recruited in a precise order based on motor neuron size (smallest to largest). 2. Explains that small motor units (Type I / slow-twitch fibers) are recruited first under low-force conditions due to low thresholds. 3. Explains that larger motor units (Type II / fast-twitch fibers) are recruited as force requirements increase due to higher activation thresholds. 4. Identifies the functional benefit (e.g., allows for fine/smooth motor control, or prevents premature fatigue of larger/fast-twitch units).

1. As a tennis ball spins with topspin, its fuzzy surface drags a boundary layer of air around with it. 2. At the top of the ball, the boundary layer moves in the opposite direction to the oncoming airflow, causing a collision of air currents that reduces the air velocity. 3. At the bottom of the ball, the boundary layer moves in the same direction as the oncoming airflow, which increases the velocity of the air moving underneath. 4. According to Bernoulli's principle, high fluid velocity results in low pressure, and low velocity results in high pressure. This creates a pressure differential (high pressure on top and low pressure on bottom), resulting in a downward Magnus force that curves the flight path of the ball downward.

Award 1 mark for each of the following: 1. Mentions that the spinning ball drags a boundary layer of air around it. 2. Explains that air velocity is reduced at the top of the ball (where boundary layer and oncoming airflow move in opposite directions). 3. Explains that air velocity is increased at the bottom of the ball (where boundary layer and oncoming airflow move in the same direction). 4. Applies Bernoulli's principle (high velocity equals low pressure, and vice versa) to explain the resulting pressure differential and the downward Magnus force/flight path curve.

1. Massed practice is a practice structure characterized by continuous practice trials with very short or no rest intervals between them, whereas distributed practice features shorter practice trials interspersed with relatively long rest intervals (where rest is equal to or longer than work time). 2. Massed practice rapidly accelerates physical and mental fatigue due to the absence of recovery opportunities during the session. 3. This high level of fatigue in massed practice can temporarily impair coordination and lead to a decline in skill performance quality during the practice session. 4. Distributed practice allows adequate physical recovery between trials, which minimizes fatigue, maintains higher motivation, and leads to more consistent, high-quality skill performance during the session.

Award 1 mark for each of the following: 1. Distinguishes massed practice (continuous, minimal rest) from distributed practice (spaced, substantial rest). 2. Explains that massed practice leads to high levels of physical and mental fatigue, while distributed practice allows for physiological recovery. 3. Explains that the fatigue in massed practice can temporarily decrease the performance quality of skills during the session. 4. Explains that distributed practice helps maintain a higher, more consistent level of skill performance during practice.

Dehydration leads to a decrease in blood plasma volume. This reduction in plasma volume decreases venous return to the heart, which in turn reduces stroke volume. Since cardiac output is the product of stroke volume and heart rate, the heart rate must increase to compensate for the reduced stroke volume to maintain cardiac output, a phenomenon known as cardiovascular drift.

Award [1] for identifying a reduction in blood plasma volume. Award [1] for linking this to a decrease in stroke volume or venous return. Award [1] for explaining the compensatory increase in heart rate to maintain cardiac output / cardiovascular drift.

In the 2 to 4 hours before a marathon, the athlete should focus on a meal high in low-to-moderate glycemic index (GI) carbohydrates. These carbohydrates provide a slow, sustained release of glucose into the bloodstream, topping up muscle and liver glycogen stores without triggering a rapid insulin spike and subsequent reactive hypoglycemia. Additionally, the meal should be low in fat, fiber, and protein to ensure rapid gastric emptying and minimize the risk of gastrointestinal discomfort during the race.

Award [1] for recommending a meal high in low-to-moderate glycemic index (GI) carbohydrates. Award [1] for explaining that this provides a sustained release of glucose / tops up glycogen without causing an insulin spike or reactive hypoglycemia. Award [1] for recommending low fat, fiber, or protein to optimize gastric emptying / minimize gastrointestinal distress.

Intrinsic motivation refers to participating in an activity for the inherent pleasure, satisfaction, and enjoyment derived from the activity itself. Extrinsic motivation refers to engaging in an activity to obtain separate outcomes or external rewards such as trophies, money, or praise. According to cognitive evaluation theory, if an athlete perceives an extrinsic reward as controlling (e.g., performing solely to get the reward) rather than informational, it diminishes their perceived autonomy and self-determination, thereby reducing their intrinsic motivation.

Award [1] for defining intrinsic motivation (internal enjoyment/satisfaction). Award [1] for defining extrinsic motivation (external rewards/consequences). Award [1] for explaining how controlling extrinsic rewards diminish autonomy/self-determination, reducing intrinsic motivation.

Cognitive anxiety represents the mental component of anxiety, which includes negative expectations, worry, self-doubt, and apprehension. Somatic anxiety represents the physical component of anxiety, which refers to the athlete's perception of their physiological arousal and bodily activation. A physiological symptom of somatic anxiety is an increased heart rate, sweating, muscle tension, or stomach butterflies.

Award [1] for describing cognitive anxiety as the mental/worry component. Award [1] for describing somatic anxiety as the physical/physiological activation component. Award [1] for identifying a valid physiological symptom of somatic anxiety (e.g., increased heart rate, muscle tension, sweating, nausea).

Chronic resistance training induces myofibrillar hypertrophy, which is an increase in the cross-sectional area of individual muscle fibers (not hyperplasia, which is an increase in fiber number). This adaptation is characterized by an increase in the size and number of myofibrils within each muscle fiber. Specifically, there is an upregulation of protein synthesis leading to an increased abundance of the contractile proteins actin and myosin, which ultimately increases force-generating capacity.

Award [1] for identifying that hypertrophy increases individual muscle fiber size (rather than fiber number). Award [1] for explaining that myofibrillar hypertrophy involves an increase in the size and number of myofibrils within the muscle fiber. Award [1] for explaining that increased synthesis of actin and myosin increases the cross-sectional area / force capacity of the muscle.

To curve a soccer ball, the player strikes it off-center, which imparts spin. As the ball rotates, it drags a boundary layer of air around with it. On the side of the ball where the spin direction aligns with the oncoming airflow, the relative air velocity increases, creating a zone of low pressure (according to Bernoulli's principle). On the opposite side where the spin opposes the oncoming airflow, relative velocity decreases, creating a zone of high pressure. This pressure difference creates a lateral force (the Magnus force) that pushes the ball from high to low pressure, curving its flight path.

Award [1] for stating that the player applies eccentric force (strikes off-center) to impart spin. Award [1] for explaining that spin creates a difference in relative air velocity on opposite sides of the ball (Bernoulli's principle). Award [1] for explaining that the resulting pressure differential (high pressure to low pressure) exerts a lateral force that curves the flight path.

Internal imagery involves the athlete visualizing the execution of a skill from their own perspective, seeing what they would see and feeling what they would feel (kinesthetic sense) during actual performance. External imagery involves the athlete visualizing themselves from an outside perspective, as if watching a video of their own performance. PETTLEP is a framework that optimizes performance by maximizing the functional equivalence between the mental imagery and physical practice using seven elements: Physical, Environment, Task, Timing, Learning, Emotion, and Perspective.

Award [1] for distinguishing internal imagery (first-person/from within the body). Award [1] for distinguishing external imagery (third-person/watching from the outside). Award [1] for explaining that PETTLEP optimizes performance by enhancing functional equivalence / aligning imagery with physical execution through its seven specific components.

Massed practice is a practice schedule where the amount of rest between practice trials is very short, meaning the practice is nearly continuous. Distributed practice involves longer rest intervals between active trials, which are often equal to or greater than the duration of the trials themselves. For a novice learning a complex gymnastics routine, distributed practice is highly recommended because it helps prevent physical fatigue and cognitive overload, decreases the risk of injury, and allows the learner time to mentally consolidate the skill between trials.

Award [1] for contrasting massed practice (continuous, minimal rest). Award [1] for contrasting distributed practice (frequent or longer rest intervals). Award [1] for explaining why distributed practice is superior for novices (reduces fatigue/injury risk, prevents cognitive overload, enhances motor learning/consolidation).

During ultra-endurance events, athletes sweat extensively, losing water and sodium. If they replace fluid losses solely with plain water (hypotonic fluid) in excess, or if they secrete excessive antidiuretic hormone (ADH), the extracellular sodium concentration becomes critically diluted (less than 135 mmol/L). This osmotic imbalance causes water to shift from the extracellular fluid into the cells, leading to intracellular swelling. In the brain, this swelling causes cerebral edema, resulting in symptoms such as confusion, headache, seizures, or coma.

[1 mark] Identify the primary cause as the over-consumption of hypotonic fluids (water) combined with significant sodium loss through prolonged sweating. [1 mark] Explain the physiological mechanism: a decrease in extracellular sodium concentration (dilution effect) leading to an osmotic gradient. [0.67 marks] Describe the consequence: water shifts into cells, causing swelling (cellular edema), which leads to neurological symptoms like headache, confusion, or seizures. Accept: references to over-hydration/water intoxication. Reject: simply saying 'dehydration' without explaining the dilution of sodium.

At high altitude, the partial pressure of oxygen in the inspired air is reduced, leading to a lower arterial oxygen saturation (hypoxemia). To compensate and maintain adequate oxygen delivery to active tissues, the sympathetic nervous system is stimulated, increasing resting and submaximal heart rate. Consequently, cardiac output is increased during submaximal exercise. However, stroke volume remains the same or may decrease slightly due to a rapid reduction in plasma volume caused by hyperventilation and increased fluid loss.

[1 mark] Explain that arterial hypoxia/reduced oxygen saturation triggers sympathetic nervous system activation. [1 mark] Identify that resting and submaximal heart rate and cardiac output increase to maintain tissue oxygenation. [0.67 marks] State that stroke volume remains unchanged or decreases due to a reduction in plasma volume (dehydration/hyperventilation). Accept: references to increased breathing rate leading to fluid loss. Reject: statements that maximal heart rate increases (maximal heart rate actually remains unchanged or decreases slightly at altitude).

In the sliding filament theory, calcium ions are released from the sarcoplasmic reticulum and bind to troponin. This binding causes a conformational change in tropomyosin, shifting it to expose the active binding sites on actin filaments. Adenosine triphosphate (ATP) then binds to the myosin head, causing it to detach from the actin filament. The hydrolysis of ATP into ADP and inorganic phosphate provides the energy required to 'cock' or reset the myosin head into a high-energy position, allowing it to bind to the next actin site and perform the power stroke.

[1 mark] Explain that calcium ions bind to troponin, causing a conformational change in tropomyosin that exposes myosin-binding sites on actin. [1 mark] State that ATP binding to the myosin head is necessary for the detachment of the cross-bridge from actin. [0.67 marks] Explain that the hydrolysis of ATP (to ADP + Pi) provides the energy to reposition/cock the myosin head for the next contraction cycle. Accept: descriptions of 'cross-bridge cycle' stages. Reject: confusing the roles of actin and myosin.

When a soccer ball is kicked with spin, it drags a boundary layer of air around with it. On the side of the ball where the spin direction matches the direction of the oncoming airflow, the relative air velocity increases. On the opposite side, where the spin opposes the oncoming airflow, the relative air velocity decreases. According to Bernoulli's principle, an increase in fluid velocity is accompanied by a decrease in pressure. Thus, a high-pressure zone is created on the slow-velocity side and a low-pressure zone on the high-velocity side. This pressure difference generates a lift force (the Magnus force) pointing towards the low-pressure side, causing the ball to curve.

[1 mark] Explain that the rotation of the ball drags air, creating higher relative air velocity on one side (where spin matches airflow) and lower relative velocity on the other (where spin opposes airflow). [1 mark] Apply Bernoulli's principle: higher fluid velocity results in lower pressure, creating a pressure differential across the ball. [0.67 marks] State that the pressure differential produces a net force (Magnus force) from the high-pressure side to the low-pressure side, curving the ball's trajectory. Accept: clear diagrams described in text. Reject: attributing the curve solely to gravity or air resistance without pressure differences.

Under the PETTLEP model of motor imagery, the physical element refers to replicating the exact somatic sensations, body position, clothing, and equipment of the performance. For example, a basketball player performs imagery while standing, holding a basketball, and wearing their uniform. The environmental element refers to the physical setting where the behavior is performed. For example, the same basketball player performs imagery while standing on the actual court or by listening to a recording of crowd noise to match the competitive environment.

[1 mark] Define the physical element (replicating physical state, posture, and equipment) with a relevant sporting example (e.g., wearing full gear). [1 mark] Define the environmental element (replicating the venue or ambient conditions) with a relevant sporting example (e.g., imagining on the competitive field or with crowd noise). [0.67 marks] Contrast the two: physical focuses on internal/somatic preparation and personal equipment, whereas environmental focuses on external surroundings. Accept: any valid sports-related examples. Reject: general definitions without sports examples.

Schmidt's schema theory proposes that movements are not stored as individual motor programs, but rather as Generalized Motor Programs (GMPs) that contain a general pattern of movement. When a tennis player faces a novel situation, they use their recall schema to determine the specific parameters needed (such as speed, force, and angle of the racket). The recall schema relies on two sources of information: the initial conditions (e.g., position of the ball and wind) and the response specifications (e.g., how fast the ball needs to be hit). This allows the player to scale and parameterize the GMP to produce a successful novel movement. After execution, the recognition schema evaluates the outcome using sensory feedback.

[1 mark] Explain that the player retrieves a Generalized Motor Program (GMP) representing the general class of movements (the forehand). [1 mark] Explain the role of the recall schema in generating specific parameters (force, angle) based on initial conditions and response specifications. [0.67 marks] Describe how the movement is executed and evaluated by the recognition schema using sensory feedback to update future schemas. Accept: mention of 'parameterization' or 'scaling' of movements. Reject: claiming that each unique movement has its own completely separate motor program.

The multidimensional anxiety theory suggests that cognitive anxiety (worry, negative thoughts) has a negative linear relationship with performance, meaning that as cognitive anxiety increases, performance continuously decreases. Somatic anxiety (physiological arousal symptoms like increased heart rate) has an inverted-U relationship, where performance is optimal at moderate levels. In contrast, catastrophe theory examines the interaction between the two. It proposes that somatic anxiety/physiological arousal is beneficial up to an optimal point, but if cognitive anxiety is also high, any further increase in arousal causes a sudden, catastrophic drop in performance rather than a gradual decline. Performance can only be recovered if arousal is drastically reduced.

[1 mark] Describe the multidimensional theory: cognitive anxiety has a negative linear relationship with performance, while somatic anxiety has an inverted-U relationship. [1 mark] Describe catastrophe theory: physiological arousal increases performance up to an optimal point, but a combination of high cognitive anxiety and high physiological arousal leads to a sudden ('catastrophic') drop in performance. [0.67 marks] Contrast the nature of performance decline: gradual and independent in multidimensional theory versus sudden, interactive, and catastrophic in catastrophe theory. Accept: clear diagrams described in text. Reject: confusing cognitive (mental) and somatic (physical) anxiety definitions.