NSCA-CPSS key terms

The relationship describing how the force a muscle or athlete can produce decreases as movement velocity increases. Practitioners use it to identify whether an athlete is force- or velocity-deficient and to target training accordingly.

The inverted-U curve showing that mechanical power output peaks at an intermediate load (commonly near 30-60% of one-repetition maximum for many lifts) and declines at very light or very heavy loads.

The slope of the force-time curve, reflecting how quickly an athlete can generate force after the onset of contraction. High RFD matters in brief explosive actions such as sprinting, jumping, and change of direction.

A plot of ground reaction force against time during a movement such as a jump or sprint start. Its shape reveals impulse, peak force, and timing characteristics that inform training and return-to-play decisions.

The product of force and the time over which it acts, equal to the change in momentum. In sport, accumulating impulse during short ground contacts is central to jumping and sprinting performance.

A rapid eccentric stretch immediately followed by a concentric contraction, which stores and reuses elastic energy and enhances force output. It underlies plyometric actions like countermovement jumps and bounding.

A muscle action in which the muscle lengthens while producing force, absorbing energy and controlling motion. Eccentric strength supports deceleration, landing mechanics, and injury resilience.

The process of reducing speed, requiring eccentric strength and coordinated braking mechanics. Effective deceleration underpins safe change of direction and is often a limiting factor in agility performance.

A planned, premeditated alteration of movement direction, distinct from reactive agility. COD tests and training target braking, reorientation, and reacceleration qualities.

A rapid whole-body movement with change of velocity or direction in response to a stimulus. It combines physical qualities with perceptual and decision-making components rather than being purely a speed attribute.

Exercises that train an athlete's ability to perceive, interpret, and act on sport-specific visual and contextual information, such as scanning, anticipation, and decision-making under time pressure.

A method in which bar velocity is measured during resistance exercise to estimate load, fatigue, and readiness. It allows autoregulation of training intensity based on daily performance rather than fixed percentages.

A near-linear association between the load lifted and the mean or peak velocity of the bar for a given exercise. It permits estimation of one-repetition maximum and prescription of velocity targets.

The greatest load an athlete can lift once with acceptable technique. It is a foundational reference for prescribing relative intensity, though it carries fatigue and injury considerations.

Adjusting training loads or volume on a given day based on an athlete's readiness or performance markers. It accommodates day-to-day fluctuations in fatigue and adaptation.

Wearable satellite-based technology that records an athlete's position, speed, and distance during training or competition. It provides external load metrics such as total distance and high-speed running.

A stadium- or facility-based tracking system using fixed receivers to locate athletes with higher indoor accuracy than satellite GPS. It supports detailed movement and load analysis in team sports.

The physical work performed by an athlete, expressed as distance, speed, acceleration, or number of jumps. It is objective and often captured by wearable or video-based tracking technologies.

The physiological or perceptual response of an athlete to training, such as heart rate, blood lactate, or rating of perceived exertion. It reflects how the athlete experiences the imposed external load.

A method that multiplies a session's perceived exertion rating by its duration to estimate internal training load. It is inexpensive, widely used, and reasonably valid for monitoring purposes.

A composite accelerometer-derived metric summarizing accumulated movement in three planes. It provides a practical index of external load that can be compared across sessions and athletes.

A ratio comparing recent (often one-week) training load with a longer rolling average (often four weeks). It is used as a monitoring heuristic for load spikes, though its predictive validity is debated.

A measure of day-to-day variability in training load, calculated as the mean weekly load divided by its standard deviation. High monotony indicates repetitive loading and has been linked to illness and stagnation.

A composite index combining weekly training load and training monotony. It reflects the overall stress imposed by a training week and helps flag excessive or poorly varied loading.

The extent to which a test or device measures what it is intended to measure. Strong validity is a prerequisite before any measurement is used to guide training or selection decisions.

The consistency and reproducibility of measurements across repeated trials or testing occasions. Reliable data are necessary for detecting real change rather than noise.

A relative measure of dispersion equal to the standard deviation divided by the mean. In testing, it quantifies typical measurement error and helps judge whether a change exceeds noise.

The smallest change in a performance measure that is meaningful to the athlete or sport. It is often estimated as a fraction of between-athlete variability and used to interpret test results.

The standard deviation of repeated measurements in a single individual, representing random measurement noise. It is used to set thresholds for real change and to compare test reliability.

A statistical approach that interprets outcomes in terms of probabilities of benefit, harm, or trivial effects relative to a smallest worthwhile change. It emphasizes practical significance over binary significance testing.

A range of values likely to contain the true population parameter, given the observed data and a chosen confidence level. It conveys the precision of an estimate rather than a single point value.

A study design in which participants are randomly assigned to intervention or control groups to reduce bias. It provides strong causal evidence, though it can be difficult to conduct in elite sport settings.

An unmeasured factor that influences both the presumed cause and the outcome, distorting the apparent relationship. Careful design and statistical control are needed to address it.

A structured, protocol-driven synthesis of all relevant studies on a focused question. It reduces bias and, when combined with meta-analysis, provides the highest level of evidence for many questions.

A ranking of study designs by their susceptibility to bias and strength for causal inference, typically placing systematic reviews and randomized trials above observational designs and expert opinion.

A systematic process of identifying the physical, technical, tactical, and psychological demands of a sport and the athlete's current capacities. It grounds program design in sport-specific priorities.

Breaking a sport or position into its key movements, work-to-rest patterns, and energetic demands. It identifies which qualities are most relevant and how they should be prioritized in training.

The balance between periods of effort and recovery within a sport or training session. It determines the dominant energy systems and informs conditioning prescription.

Comparing the demands identified in a needs analysis with an athlete's current test results to reveal priority deficits. It directs training toward the qualities most likely to improve performance.

A coordinated set of tests selected to assess the qualities prioritized by a needs analysis. It should be valid, reliable, feasible, and organized to minimize fatigue-related interference.

The systematic planning of training over time, dividing the annual plan into phases with specific objectives. It manages fatigue, peaking, and long-term development.

A focused period, often several weeks, emphasizing a limited set of training targets. Blocks are sequenced to build on prior adaptations and to manage competing demands.

A planned reduction in training load before competition to dissipate fatigue while preserving fitness. It typically involves reduced volume with maintained intensity and lasts one to three weeks.

The phase in which an athlete achieves optimal readiness for a target competition. It requires balancing accumulated fitness against fatigue through carefully timed load reduction.

The principle of gradually increasing training stress as the athlete adapts, so that continued improvement occurs. Increases should be planned and monitored to avoid excessive load spikes.

Tailoring training prescription to an athlete's capacities, history, recovery, and goals. It recognizes that identical programs produce different responses across individuals.

The principle that training adaptations are most pronounced for the specific qualities, movement patterns, and contexts that are trained. Programs should mirror the demands of the sport where feasible.

The capacity to perform repeated short maximal sprints with limited recovery while maintaining performance. It is a key fitness determinant in many team and racket sports.

Training designed to improve the phosphagen, glycolytic, and oxidative systems according to sport demands. Prescription uses work-to-rest ratios, intensity, and duration to target specific adaptations.