NESTA SAQ key terms

A nutrient the body requires in large amounts to supply energy and building material: carbohydrate, protein, and fat. Alcohol also yields energy but is not considered an essential macronutrient.

An energy-yielding nutrient built from sugar units, stored as glycogen in muscle and liver and circulating as blood glucose. It fuels high-intensity work and supports brain function during demanding training.

The branched storage form of glucose held in muscle and liver. Muscle glycogen fuels local contraction; liver glycogen releases glucose into the blood to keep blood sugar stable between meals and overnight.

A ranking of how quickly a fixed portion of a carbohydrate-containing food raises blood glucose compared with a reference food. It is influenced by fiber, processing, ripeness, and how the food is combined.

One of nine amino acids the body cannot synthesize in adequate amounts and must obtain from food. Their presence, especially leucine, triggers muscle protein synthesis after a protein-containing meal.

The extent to which a protein source supplies essential amino acids in proportions that support growth and repair. It is commonly scored by digestibility-corrected amino acid composition rather than by grams alone.

The amount of leucine in a single feeding, roughly two to three grams for most adults, believed necessary to maximally stimulate muscle protein synthesis. Meeting it per meal matters more than daily total alone.

The kilocalories provided per unit weight or volume of a food. Low-density foods such as vegetables and soups promote fullness at lower energy intake, while high-density foods favor energy surplus.

A vitamin or mineral required in small amounts that does not supply energy but enables metabolism, oxygen transport, bone health, and immune function. Deficiencies can impair performance before clinical signs appear.

The proportion of a consumed nutrient that is absorbed and used by the body. It depends on food form, absorption enhancers and inhibitors, and the individual's nutritional and health status.

The body's iron stores and supply, assessed through ferritin, hemoglobin, and related markers. Low stores reduce oxygen-carrying capacity and are common in endurance athletes, especially menstruating individuals.

A charged mineral such as sodium, potassium, magnesium, or chloride that conducts electrical signals and governs fluid movement between compartments. Sweat losses of sodium and chloride are the largest during exercise.

The state of body water balance sufficient to support normal physiological function. Adequate hydration before, during, and after exercise protects plasma volume, thermoregulation, and cardiovascular stability.

The volume of sweat lost per hour of exercise, estimated by comparing body mass before and after a session while accounting for fluid intake and urine output. It varies widely between individuals and conditions.

A dangerously low blood sodium concentration that can occur when fluid intake far exceeds sweat and urine losses, especially in long events. Symptoms include nausea, headache, confusion, and in severe cases seizures.

The immediate energy system that regenerates ATP from stored phosphocreatine for roughly the first ten seconds of maximal effort. It requires no oxygen and recovers quickly between short bursts.

The breakdown of glucose or glycogen to lactate without oxygen, producing ATP rapidly for high-intensity efforts lasting roughly ten seconds to two minutes. Hydrogen ion accumulation contributes to fatigue.

The oxygen-dependent pathway that produces the most ATP by breaking down carbohydrate and fat through the Krebs cycle and electron transport chain. It dominates during sustained submaximal exercise.

The exercise intensity at which blood lactate begins to rise faster than it can be cleared, marking a shift toward greater reliance on glycolysis. It is a strong predictor of endurance performance.

The maximum rate at which the body can consume oxygen during intense exercise, expressed per kilogram of body mass. It reflects cardiorespiratory capacity and sets the ceiling for aerobic energy production.

The ratio of carbon dioxide produced to oxygen consumed during metabolism. Values near 0.7 indicate mostly fat use, near 1.0 mostly carbohydrate, and above 1.0 suggest hyperventilation or intense effort.

The relationship between energy consumed from food and energy expended through metabolism, physical activity, and thermogenesis. A sustained surplus promotes weight gain; a sustained deficit promotes weight loss.

The energy expended at rest to maintain vital functions such as breathing, circulation, and cell turnover. It typically accounts for the largest share of daily energy expenditure in most people.

The proportion of fat mass and fat-free mass in the body, often estimated by skinfolds, bioelectrical impedance, or densitometry. It is more informative for athletes than body mass alone.

A field technique that estimates subcutaneous fat by pinching skin and fat at defined sites with calipers. Reliability depends on technician skill, consistent sites, and the prediction equation used.

A structured evaluation of dietary intake, anthropometrics, biochemical markers, and clinical and social history to identify nutrition needs and risks. It forms the basis for individualized intervention planning.

A prospective log in which a client records everything eaten and drunk over a set period, ideally including portions. It can be detailed but is prone to underreporting and altered eating behavior.

A strategy that increases muscle glycogen stores before endurance events by tapering training while raising carbohydrate intake in the final days. It benefits events lasting roughly ninety minutes or longer.

The progressive reduction of stored carbohydrate during prolonged or repeated exercise, associated with fatigue, reduced intensity, and perceived heaviness. Adequate intake and tapering help prevent it.

The deliberate scheduling of food and fluid around training and competition to optimize fuel availability, recovery, and adaptation. It includes pre-event meals, during-event fueling, and post-exercise recovery intake.

Distributing protein intake evenly across the day in moderate doses that each reach the leucine threshold, rather than concentrating it in one meal. This pattern supports muscle protein synthesis throughout the day.

The cellular process of building new muscle protein from amino acids, stimulated by feeding and mechanical loading and suppressed during fasting. Net muscle gain requires synthesis to exceed breakdown over time.

Any substance, device, or practice used with the intent of improving exercise performance or recovery. Claims should be evaluated against credible evidence for efficacy, safety, legality, and contamination risk.

A compound stored in muscle as phosphocreatine that helps regenerate ATP during brief maximal efforts. Supplementation can increase strength and lean mass, and it is among the most studied sports supplements.

A central nervous system stimulant that can reduce perceived exertion and improve endurance and power output. Effective doses are moderate, and timing and individual tolerance influence both benefit and side effects.

Independent laboratory screening of supplements for prohibited substances and label accuracy. Choosing certified products reduces, though does not eliminate, the risk of inadvertent doping for athletes.

A syndrome caused by insufficient energy availability that impairs metabolism, bone health, immunity, and performance. It can affect both male and female athletes and requires multidisciplinary assessment and care.

The boundaries of what a practitioner is trained, licensed, and permitted to do. Sports nutrition professionals provide general guidance within their competence and refer clinical concerns to qualified clinicians.