G-actin – A globular protein that forms the building blocks of thin muscle filaments.

Gait cycle – The sequence of movements from one foot strike to the next of the same foot during walking or running.

Game-centred learning – A teaching approach using modified games to develop tactical and technical skills.

Game sense – A coaching model that develops understanding of tactics through gameplay.

Gamma motor neuron – A nerve that controls the sensitivity of muscle spindles to stretch.

Gastrocnemius – The large calf muscle involved in plantarflexion at the ankle.

Gate control theory – A theory suggesting that non-painful stimuli can block the sensation of pain.

Gender bias – Unequal treatment or expectations in sport based on gender.

General adaptation syndrome (GAS) – The body’s response to stress in three stages: alarm, resistance, exhaustion.

General fitness – A state of overall physical wellbeing not specific to one sport.

Generalised motor programme – A stored pattern of movement that can be adjusted for different tasks.

Genetic predisposition – An inherited tendency to develop certain traits or capacities (e.g. aerobic potential).

Genotype – The genetic makeup of an individual that influences physical characteristics.

Geotemporal training load – A model that considers time, location, and context when planning training.

Giant sets – A resistance training method involving four or more exercises for the same muscle group.

Glucagon – A hormone that raises blood glucose by stimulating the liver to release stored glucose.

Glucocorticoids – Hormones that help regulate metabolism and immune response under stress.

Glucose – A simple sugar used as a primary energy source during exercise.

Gluteus maximus – The large muscle in the buttocks responsible for hip extension.

Glycaemic index (GI) – A measure of how quickly carbohydrate foods raise blood sugar levels.

Glycaemic load (GL) – A measure that considers both the quality and quantity of carbohydrate in food.

Glycogen – The stored form of glucose found in the liver and muscles.

Glycogen loading – A strategy to increase muscle glycogen stores before endurance events.

Glycolytic system – The anaerobic energy system that breaks down glucose to produce ATP and lactate.

Goal gradient effect – The tendency to increase effort as one gets closer to achieving a goal.

Goal setting – Establishing objectives to improve motivation, focus, and performance.

Golgi tendon organ – A receptor that senses tension in muscles and helps prevent over-contraction.

Graded exercise test (GXT) – A fitness test where intensity increases gradually to assess aerobic capacity.

Graduated compression – Clothing or garments designed to improve circulation and recovery.

Gravitational force – The force pulling the body downward, affecting movement and balance.

Grip dynamometer – A tool used to measure hand and forearm strength.

Groin strain – A tear or stretch of the adductor muscles in the inner thigh.

Gross motor skill – A skill involving large muscle groups and whole-body movement.

Gross movement – Movement that is powerful and general rather than precise.

Ground contact time – The time a foot is in contact with the ground during running.

Ground reaction force (GRF) – The force exerted by the ground on the body when it contacts a surface.

Group cohesion – The strength of relationships and unity among members of a team.

Growth hormone (GH) – A hormone that stimulates growth, cell repair, and muscle development.

Guided discovery – A coaching technique that helps learners find answers through exploration and questioning.

Gustatory feedback – Information gained through the sense of taste (e.g. dehydration detection).

Glycaemic response – The effect a food has on blood sugar after eating.

Gymnastics-based conditioning – Strength and mobility training using bodyweight and dynamic movement patterns.

Gyroscope – A tool used in sport tech to measure orientation and angular velocity.

Glycoprotein – A molecule made of protein and carbohydrate, often involved in cell recognition and immunity.

Graded potential – A small change in electrical charge in a nerve cell that may lead to an action potential.

Group dynamics – The behavioural relationships and roles within a team or performance group.

Gas transport – The movement of oxygen and carbon dioxide via the blood.

Glycogen sparing – The ability to use fats for energy, conserving glycogen during endurance exercise.

Goal orientation – An individual’s reason for engaging in sport (e.g. mastery vs. performance goals).

Game model – A tactical framework used to teach or analyse sport-specific play.