IB Sports, exercise and health science A.2.2 Fuelling for Health and Performance Key Definitions

Body fat that stores energy and fat-soluble vitamins.

A condition in which the immune system mistakenly attacks the body’s own cells

A diet that provides all essential nutrients (carbohydrate, lipid, protein, water, vitamins, minerals) in the right amounts to maintain health and prevent both nutrient deficiency and nutrient excess.

The amount of energy required by the body to maintain basic physiological functions at rest.

Essential amino acids (leucine, isoleucine, valine) that support muscle protein synthesis and recovery, influenced by gut microbiome activity.

Carbohydrate loading is a dietary strategy aimed at increasing muscle glycogen stores before endurance events.

A supplement that enhances ATP replenishment, muscle hydration, and recovery from high-intensity exercise.

Substances that increase urine production, leading to fluid loss (e.g., caffeine, alcohol, certain medications).

An imbalance in the gut microbiome, where harmful microbes outnumber beneficial ones, potentially leading to digestive issues, inflammation, and metabolic disorders.

An amino acid that the human body cannot synthesise on its own and must obtain through the diet. There are nine essential amino acids: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine, and histidine.

A B vitamin essential for DNA synthesis, cell division, and preventing neural tube defects in developing fetuses.

The production of glucose from non-carbohydrate sources, such as proteins and fats.

A measure of how quickly carbohydrates raise blood glucose levels, with high-GI foods promoting faster glycogen replenishment.

The stored form of glucose found in the liver and muscles, which can be broken down into glucose for ATP production during exercise.

The gut microbiome refers to the collection of microorganisms living in the digestive system, particularly in the intestines.

A two-way communication system between the gastrointestinal tract and the central nervous system, linking the gut and the brain through endocrine, immune, metabolic and neural pathways.

The gut-brain axis is the bidirectional communication between the gut microbiome and the brain.

The bidirectional communication system between the gut microbiome and the central nervous system, influencing mood, cognition, and stress response.

An iron-rich pigment in red blood cells that binds oxygen in the lungs and transports it to the body's tissues, then helps return carbon dioxide to the lungs.

An iron-rich pigment in red blood cells that binds oxygen in the lungs and transports it through the blood to the body's tissues, and helps return carbon dioxide to the lungs.

Hypertrophy refers to the increase in the size of muscle fibers.

The process of releasing triglycerides from fat stores and breaking them down into glycerol and fatty acids, which can then be used to produce energy via beta-oxidation.

A state in which the body has insufficient energy left over, after exercise, to support the physiological functions needed for optimal health. Defined as below 30 kcal per kg of fat-free mass per day in biological females.

Macronutrients are nutrients required in large amounts that provide energy necessary for sustaining physiological functions and supporting physical activity.