Capillarisation – The increase in capillary networks around muscles to improve oxygen delivery.

Cardiac hypertrophy – The enlargement of the heart muscle due to regular aerobic training.

Cardiac output – The volume of blood pumped by the heart per minute.

Cardiovascular drift – A gradual increase in heart rate during prolonged exercise due to fluid loss.

Cardiovascular endurance – The ability of the heart and lungs to supply oxygen during continuous activity.

Cartilage – A tough, flexible connective tissue that reduces friction between bones.

Centre of gravity – The point at which the body’s mass is balanced in all directions.

Centre of mass – The average location of a body’s weight distribution.

Cerebellum – The part of the brain that controls coordination and balance.

Cerebral cortex – The brain area responsible for conscious thought and voluntary movement.

Cerebrum – The largest brain region, managing complex sensory and motor functions.

Circuit training – A series of exercises performed one after the other with brief rest periods.

Closed kinetic chain – Exercises where the limb is fixed and movement occurs through multiple joints.

Closed loop control – A model of skill execution that uses feedback during the movement.

Closed skill – A skill performed in a predictable and stable environment.

CNS (Central Nervous System) – The brain and spinal cord, controlling voluntary and involuntary actions.

Cognitive anxiety – Negative thoughts and worry experienced before or during performance.

Cognitive rehearsal – Mentally practising a skill or performance to improve execution.

Cognitive stage of learning – The first phase of learning where understanding and trial-and-error dominate.

Cognitive skill – A skill that involves decision-making and thinking processes.

Coefficient of friction – A measure of the resistance between two surfaces in contact.

Cohesion – The level of unity and cooperation within a group or team.

Collagen – A structural protein in connective tissue such as ligaments and tendons.

Collision sport – A sport involving deliberate and forceful contact, like rugby or American football.

Concentric contraction – A muscle contraction that shortens the muscle while producing force.

Conditioning – Physical training aimed at improving fitness and performance.

Confidence – The belief in one’s ability to succeed in a task or performance.

Conservation of momentum – A physics principle stating that total momentum remains constant in a system.

Continuous skill – A movement with no clear beginning or end, such as running or cycling.

Continuous training – Exercise at a steady intensity without rest, improving aerobic endurance.

Coordination – The ability to use different body parts together smoothly and efficiently.

Core stability – Strength and control of muscles around the trunk and pelvis.

Coronary arteries – The blood vessels that supply the heart muscle with oxygen-rich blood.

Cortisol – A stress hormone that increases blood sugar and suppresses immune function.

Couch to 5K – A beginner running programme that builds endurance gradually over several weeks.

Cranium – The part of the skull that encloses the brain.

Creatine – A compound used in high-intensity energy production, stored in muscles.

Creatine phosphate – A quick-release energy source for explosive, short-duration activity.

Creatine supplementation – A legal ergogenic aid that boosts phosphocreatine levels in muscles.

Critical period – A time during development when learning a skill is easiest and most effective.

Cross training – Using different types of exercise to improve overall fitness and prevent overuse injuries.

Crossover concept – The shift in fuel use from fats to carbohydrates as exercise intensity increases.

Cultural influence – The impact of societal values and norms on participation in physical activity.

Cumulative fatigue – Fatigue that builds up over time due to repeated training or insufficient rest.

CV (Cardiovascular) system – The system responsible for pumping and circulating blood through the body.

Cycle ergometer – A stationary bike used in lab testing to measure power output.

Cyclic movement – A repetitive motion pattern, like swimming, walking, or cycling.

Cytoplasm – The fluid inside cells where energy production and chemical reactions take place.

Cytoskeleton – A network of fibres inside cells that helps with structure and movement.

Cytosol – The fluid part of the cytoplasm where metabolic processes occur.