Fatigue can originate at different levels of the motor or energy pathway, possibly combining a variety of sources.

With its combination of human physiology, biomechanics, nutrition, psychology, and experimental science , the IB Sports, Exercise and Health Science syllabus can initially feel like several different subjects combined into one. However, the course is structured around three connected themes , all of which are explored through the dual lenses of health and performance . In this post, we’ll break down the syllabus and explain what you can expect to study throughout the course.

The current IB Sports, Exercise and Health Science (SEHS) syllabus is designed for first assessment in 2026 . SEHS is both a human science and an experimental science , combining the study of physiology, biomechanics, and psychology with practical investigations completed in laboratory and field settings. The syllabus is organized into three main themes:

These themes are highly interconnected rather than completely separate units. For example, an athlete's performance may simultaneously depend on their energy systems, movement technique, training programme, motivation, and ability to cope with pressure. The syllabus is therefore designed to encourage students to make connections between different topics rather than simply memorize isolated facts.

Sports Science

Theme A explores how the body's physiological systems work together to support health, physical activity, and sporting performance . You will investigate communication between body systems, the maintenance of stable internal conditions, transportation of gases and nutrients, nutrition and hydration, energy production, training responses, and the health effects of physical activity.

This topic examines how different systems within the human body communicate and coordinate their functions.

This topic explores how food, water, and energy availability influence both health and performance .

You will study why maintaining appropriate levels of water and electrolytes is essential for normal physiological function. Possible areas include:

You will also examine how the hypothalamus, pituitary gland, and kidneys help regulate water and electrolyte balance.

The final topic in Theme A investigates how the body responds and adapts to training and physical activity.

Exercise physiology and nutrition of the human body

You will investigate how communication between body systems allows the body to respond to exercise and changing conditions. Areas you may study include:

The purpose is to understand the body as an integrated system rather than viewing each organ or physiological system independently.

The nervous system senses both internal and external conditions to coordinate the responses of the body’s physiological systems effectively.

The endocrine system, made up of the body's glands and hormones, regulates all biological processes in the body.

Inter-system communication

Homeostasis refers to the body's ability to maintain a relatively stable internal environment despite changes inside or outside the body. You will examine processes including:

For example, thermoregulation depends on several body systems working together through mechanisms such as sweating, vasodilation, vasoconstriction, shivering, and non-shivering thermogenesis . Factors such as training status, body composition, environmental conditions, and sex differences can also influence thermoregulation. At HL, this topic is extended to consider the body's acute responses and longer-term adaptations to environmental conditions , including temperature, humidity, and altitude.

Homeostasis is any self-regulating biological process aiming to produce a relatively stable, constant internal environment for optimal functioning of the body.

The body has acute and possible long-term responses to the environment in which it functions.

Maintaining homeostasis

The cardiovascular system transports nutrients, hormones, gases, heat and waste to perform necessary bodily functions.

The respiratory system enables the exchange of gases between the external environment and the body, to facilitate cellular respiration.

Transport

This section explores how nutrition supports the body's physiological functions and physical performance . At both SL and HL, you will investigate the three major macronutrients:

You will consider how their availability and metabolism influence health and exercise performance, as well as how nutritional requirements differ according to factors such as age, sex differences, body composition, activity level, and the demands of the sport . You will also examine nutritional strategies before and during exercise and issues such as low energy availability (LEA) and relative energy deficiency in sport (RED-S) . At HL, you will go further by studying:

Macronutrients (carbohydrates, proteins and lipids) provide sources of energy to maintain bodily functions during growth, rest and physical activity.

Micronutrients play highly specific roles in facilitating energy transfer and tissue synthesis.

The gut microbiome influences the health and performance of an individual.

Fuelling for health and performance

This section examines how the body produces ATP to support physical activity . You will study three energy systems:

Rather than operating completely separately, these systems contribute along an energy continuum . Their relative contribution varies with factors such as exercise duration and intensity . For example, the oxidative system dominates during rest and prolonged lower-intensity activity, while anaerobic pathways become increasingly important during short periods of high-intensity exercise or sudden increases in intensity.

The body relies on the phosphagen, glycolytic and oxidative systems for energy production to sustain life and physical activity.

Maximal oxygen consumption (VO2 max) is influenced by an individual’s age, sex differences, body composition, lifestyle factors and level of fitness.

The lactate inflection point is the maximum intensity at which the body can metabolize lactate at the same rate as its production.

Excess post-exercise oxygen consumption (EPOC) is required for the body to return to homeostasis and is dependent on the oxygen deficit incurred during exercise.

Energy systems

You will examine the characteristics that make physical training effective and how training programmes can be designed around the individual and the activity. This includes considering:

Rather than viewing training as simply "doing more exercise", you will consider how appropriate manipulation of training variables can produce particular physiological adaptations while reducing problems such as injury and overtraining.

The quality of training design and programme design are essential elements in developing a safe and effective programme for improving health or performance.

Qualities of training

This section examines the relationship between physical activity and long-term health . You will consider:

Regular activity can reduce the risk of several chronic conditions , although the appropriate amount and type of activity vary with factors such as age and sex. At HL, you will also consider the planning of exercise programmes for different populations , such as:

HL students additionally explore the physiological causes of fatigue and the science of recovery . Possible causes of fatigue include:

You will also evaluate indicators and strategies for recovery, including:

An active lifestyle supports physical well-being.

Prescribing exercise for health and sporting performance needs careful consideration and planning.

Benefits to health of being active

Fatigue and recovery

Biomechanics applies principles of physics and anatomy to human movement. Rather than simply describing how someone runs, jumps, throws, or strikes an object, biomechanics allows you to analyze why a movement occurs, what forces are involved, and how technique could be made more efficient, effective, or safe .

This topic focuses on the anatomical and mechanical structures that allow the human body to produce movement.

This topic applies mechanical principles more directly to sporting movement.

You will use Newtonian mechanics to explain linear and angular motion . Areas include:

For example, you will consider why applying a greater impulse produces a greater change in momentum and how changes in body position influence stability. At HL, you will extend this understanding through ideas including:

This topic examines why musculoskeletal injuries occur and how their likelihood and consequences can be reduced.

Biomechanics

You will become familiar with anatomical terminology used to describe human movement. This includes:

You will also study movement terminology such as:

At HL, this section extends into anthropometry , including the measurement of body proportions a nd its use in equipment design and ergonomics .

The human skeleton is divided into an axial component and an appendicular component.

Movements occur in one or more planes, and rotations occur along one or more axes.

Anthropometry, the measurement of body segments and proportions of the human body, has applications in many areas of sport and health science.

Anatomical position, planes and movement

You will examine the relationship between structure and function in:

You will also investigate different forms of articulation, including:

The structure of connective tissues and joints are related to their function in enabling movement.

Structure and function of connective tissues and joints

This section examines how muscles generate movement and stability . You will investigate:

At HL, you will examine the sliding filament theory , including the roles of actin, myosin, calcium, ATP, troponin, and tropomyosin in muscular contraction.

The body uses different types of muscular contractions to create movement and stability.

The sliding filament theory describes the interaction between myofilaments and the molecules responsible for sarcomere or muscle contraction.

Muscular function

The body can also be understood as a system of levers. You will study:

You will consider both levers within the body and external sporting equipment that can alter movement or enhance performance.

Three different classes of levers, both within and outside the human body, work to create movements.

Levers in movement and sport

Linear and angular motion can be analysed using Newton's laws of motion.

A collision results in a change in momentum in the colliding bodies.

The force of friction is determined by the coefficient of friction.

Work results from the application of a force over a distance.

Newton’s laws of motion

This area examines how movement through air or water affects sports performance . You will study projectile motion and consider factors such as:

The wider biomechanics of fluids can help explain the flight of sporting objects and the movement of athletes through air or water.

Movement analysis involves breaking a skill into phases so that technique can be systematically studied. The syllabus uses phases including:

Movement analysis can then be applied to improve performance, rehabilitation, accessibility, and safety .

The path of a projectile through air is determined by different factors and forces.

Environmental conditions such as temperature, humidity, air pressure, wind, salinity of water and altitude affect the external forces acting on an object.

The forces of buoyancy, lift and drag acting on a body as it moves through a fluid (air or water) have a measurable effect on its path.

Fluid mechanics

A phases-of-movement approach is used to break down and describe movements.

Movement analysis and its applications

You will distinguish between different risk factors for injury. External factors can include environmental conditions and the use or absence of protective equipment. Internal risk factors can include:

Possible injuries involve connective tissues, muscle, bone, skin, and functional concussion-like brain injuries .

The complex interaction of internal and external risk factors can predispose and make an individual susceptible to injury.

An acute trauma is caused by a sudden or excessive application of force, or by a force from an unexpected direction.

Chronic or overuse injuries are often related to technique.

Causes of injury

This area examines approaches intended to reduce injury risk . You may consider:

The overall aim is to understand how biomechanical and physiological knowledge can be used to prevent injuries and support safe return to activity .

Methods of lowering the risk of injury attempt to minimize the abnormal application of forces and maximize the ability of the body to absorb any such application of force.

The initial stages of injury treatment often involve mitigation of inflammation.

Treatment of concussion varies based on the specifics of the injury.

Interventions related to injury

Theme C examines the psychological factors that influence sporting participation, learning, performance, and well-being. Rather than focusing exclusively on elite athletes, the theme considers why people behave differently in exercise and health settings, how skills are acquired, what motivates people, and how psychological strategies can improve performance .

This topic examines why different people respond differently to the same sporting or exercise situations .

Motor learning examines how physical skills are acquired, practised, transferred, and perfected . You will study competing models of how motor learning occurs, including the information processing model and ecological model . You will also examine approaches such as:

Traditional models also describe three broad stages of skill learning:

You will investigate how coaching should change as performers progress through these stages . Other concepts include the psychological refractory period , which helps explain why responding to a second stimulus can be delayed, and transfer of learning , which examines how previous experience affects the acquisition of new skills.

This topic examines why individuals begin, continue, or withdraw from sporting and physical activities . You will investigate different explanations of motivation and consider how factors within the individual interact with the sporting environment. Possible areas include:

Sport can create significant psychological pressure . This topic examines how stress, arousal, and anxiety influence health and performance.

The final topic examines psychological interventions that can be used to enhance performance .

Sports psychology and motor learning

You will investigate personality traits and how they can influence behaviour. Personality factors may include characteristics such as:

At HL, you will also explore social learning theory , including how behaviours can be learned through observation and imitation. An important point in the syllabus is that there is no single personality profile that predicts sporting success . Behaviour results from interactions between personality, experience, learning, and environmental factors .

Personality refers to individual differences in characteristic patterns of thinking, feeling and behaving.

Social learning theory is a situational approach to understanding behaviour.

Personality can change over a long period of time.

Personality

Mental toughness examines how individuals respond to pressure and challenge . You will consider characteristics including:

Mental toughness can contribute to performance in high-pressure situations and may be developed through experience and training rather than being completely fixed. At HL, this extends into concepts such as:

Mental toughness is an aspect of personality that partly explains how individuals manage challenging and pressurized situations.

The theory of the “self-fulfilling prophecy” in sporting success suggests that a sportsperson’s perceived self-confidence results in greater persistence and effort, leading to an increased probability of eventual success.

Mental toughness is positively associated with better health outcomes, including fewer depressive symptoms, fewer burnout symptoms and improved sleep quality.

Attribution theory illustrates how perceived locus of causality, stability and control can impact subsequent self-confidence.

Mental toughness

Learning, including motor learning, is a relatively permanent change in behaviour brought about by experience, whereas performance is a temporary occurrence, fluctuating over time.

The psychological refractory period is the time in which response to a second stimulus is significantly slowed because a first stimulus is still being processed.

Transfer of learning refers to the influence of previous experience performing a skill on the learning of a new skill.

Motor learning processes

The proficient execution of specific skills requires the correct attentional focus.

Attentional control

Need achievement theory posits that personality and situational factors interact to produce resultant factors, which create emotional factors, which drive behavioural factors.

Goal orientation theory assumes that individuals strive to feel successful.

High ego orientation can be problematic if task orientation is low.

Achievement motivation

Self-determination theory hypothesizes that humans strive to satisfy needs of autonomy, competence and relatedness.

Motivation can be placed along a continuum from amotivation to controlled motivation to autonomous motivation.

Self-determination theory is a meta-theory comprising six mini-theories, each explaining a facet of individual motivation.

Self-determination

The syllabus identifies mastery climates as generally more effective for enjoyment, teamwork, and long-term performance. You will also explore how coaches can use the TARGET framework (Task, Authority, Recognition, Grouping, Evaluation, and Time) to create a mastery-oriented environment.

Motivational climate describes the psychological environment that the coach creates by designing sessions that provide instructions and feedback, which will help to motivate the athletes in training or competition.

Motivational climate

Arousal describes an individual's level of physical and psychological activation . You will investigate theories including:

You will also distinguish between different dimensions and experiences of anxiety and examine ways anxiety can be measured through subjective and physiological measurements .

Arousal refers to the level of physical and psychological activation.

When anxiety is low, individuals experience positive emotions, such as excitement, desire and elation.

Arousal and anxiety

Coping strategies can broadly be divided into:

At HL, you will investigate how the effectiveness of different strategies depends on whether the stressor is controllable or uncontrollable , as well as the particular athlete and situation.

Stressors can be considered as either controllable or uncontrollable.

Many coping strategies have been shown to be effective for athletes, although the effectiveness of each is specific to the individual and the situation.

Coping

The effectiveness of different goals depends partly on the individual and their achievement motivation . At HL, you will additionally investigate:

Goal setting directs attention to a specific task.

The goal-setting paradox explains that elite athletes often feel less satisfied when a higher goal is achieved than an easier goal.

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