WJEC A-Level PE Unit 1 Exercise Physiology, Performance Analysis and Training: a deep dive on the body systems, energy, training and nutrition

What Unit 1 actually demands

Exercise Physiology, Performance Analysis and Training is the applied-science foundation of WJEC A-Level Physical Education. The unit runs from how the body supplies energy and oxygen, through how muscles contract and adapt, to how training is designed and how diet supports it. Examiners test two linked skills: precise recall of structures and processes, and the application of those facts to sporting examples, data and calculations.

This guide walks through the six clusters of the unit in a sensible build order, then sets out the exam patterns WJEC repeats. Each cluster has a matching dot-point page with practice questions; this overview ties them together.

The cardiovascular and respiratory systems

Start with delivery. Cardiac output is heart rate multiplied by stroke volume; learn how each changes with intensity, remembering that stroke volume plateaus at around half of maximal effort while heart rate keeps climbing. Add Starling's law (more venous return means a bigger stroke volume) and the vascular shunt, in which the vasomotor centre redistributes blood to working muscles by vasodilation and away from the gut by vasoconstriction. On the respiratory side, minute ventilation is breathing frequency times tidal volume, and gaseous exchange is diffusion down partial-pressure gradients at the alveoli and the muscles. The reliable trap is confusing ventilation (air movement) with respiration (energy release in cells).

The neuromuscular system

Next, how movement is produced. A motor unit is a motor neurone and all the fibres it supplies, and by the all-or-none law those fibres fire fully or not at all, so force is graded by recruiting more units and firing them faster. The sliding filament theory explains contraction: calcium exposes binding sites, myosin cross-bridges pull actin over myosin, and ATP resets the cycle so the sarcomere shortens. Learn the three fibre types (type I slow oxidative, type IIa fast oxidative glycolytic, type IIx fast glycolytic) with their structure, function and sporting use. Finish by separating acute responses (during one session) from chronic adaptations (over weeks).

The energy systems and recovery

The energy systems are the heart of the unit. Master the ATP-PC system (phosphocreatine, no fatiguing by-product, up to about ten seconds), the anaerobic glycolytic system (glycogen to lactate, the fatiguing by-product, about ten seconds to three minutes), and the aerobic system (full oxidation of glycogen and fats to carbon dioxide and water, up to 38 ATP per glucose). Learn the energy continuum so you can match the predominant system to any activity, then recovery: EPOC, with a fast component restoring ATP and PC and a slow component clearing lactate.

Training principles, methods and periodisation

Now apply it to training. The principles are captured by SPORT (specificity, progression, overload, reversibility, tedium) and the variables by FITT (frequency, intensity, time, type). Match the method to the component: continuous and fartlek for aerobic endurance, interval for anaerobic and aerobic power, weights for strength, plyometrics for power, and stretching for flexibility. Periodisation divides the year into a macrocycle, mesocycles and microcycles, with preparation, competition and transition phases, so the athlete peaks and avoids overtraining. Keep overload (the necessary gradual increase) distinct from overtraining (too much load, too little recovery).

Fitness components and testing

Learn the physical (health-related) components (aerobic capacity, strength, muscular endurance, flexibility, body composition) and the skill-related components (speed, power, agility, balance, co-ordination, reaction time), each with a recognised test such as the multi-stage fitness test, grip dynamometer, sit-and-reach, Illinois agility run and vertical jump. The evaluation marks come from validity (does the test measure the right thing) and reliability (does it give consistent results), plus the sensible use of normative data.

Diet, nutrition and ergogenic aids

Finally, fuel. A balanced diet supplies carbohydrate (the main fuel, stored as glycogen), fat (low-intensity fuel), protein (repair), plus vitamins, minerals, fibre and water. Learn hydration and dietary strategies such as carbohydrate loading, then the ergogenic aids: creatine and caffeine (legal) with their benefits and risks, and anabolic steroids, EPO and blood doping (banned) with their dangers.

How Unit 1 is examined

A typical WJEC profile for this unit:

• Recall and short answer. Defining cardiac output, the energy systems and the fitness components; naming muscle fibre types and training methods.
• Application. Matching an energy system or training method to a named activity, and applying physiology to a games player or endurance athlete.
• Calculation. Cardiac output, minute ventilation, maximum heart rate, and reading values from graphs.
• Extended answers. The vascular shunt, the sliding filament theory, periodisation, and the evaluation of a fitness test are all predictable.

Check your knowledge

A mix of recall and application questions covering the whole of Unit 1. Attempt them under timed conditions, then check against the solutions.

1. Define cardiac output and explain how it changes from rest to maximal exercise. (4 marks)
2. Describe the vascular shunt mechanism. (3 marks)
3. Explain the sliding filament theory of muscle contraction. (4 marks)
4. Compare type I and type IIx muscle fibres and give a sporting example of each. (4 marks)
5. Name the fuel and by-product of each of the three energy systems. (3 marks)
6. Explain what is meant by EPOC and describe its two components. (4 marks)
7. Explain the principle of progressive overload using the FITT variables. (3 marks)
8. Define power as a component of fitness and name a valid test for it. (2 marks)