Terms

Adolescence

The period between childhood and adulthood, characterized by puberty and the development of secondary sex characteristics.

Adulthood

The period of life following adolescence, typically after full physical and sexual maturation.

Amenorrhea

The absence of a menstrual cycle for more than three months, often associated with low energy availability in female athletes.

Anterior Cruciate Ligament (ACL)

A major ligament in the knee, frequently injured, particularly in female athletes.

Apophyseal

Relating to an apophysis, a natural outgrowth or protuberance, especially from a bone, where muscle-tendon units insert.

Biological Age

A measure of an individual's stage of maturation or development, often assessed by skeletal maturity, somatic maturity, or sexual maturation, rather than chronological age.

Childhood

The period of life before the development of secondary sex characteristics.

Chronological Age

A person's age in months or years.

Cocontraction

The simultaneous activation of both agonist and antagonist muscle groups crossing the same joint, often used as a motor control strategy for dynamic stabilization, but can reduce net joint moments.

Development

The natural progression from prenatal life to adulthood, encompassing all physical and psychological changes.

Diaphysis

The central shaft of a long bone, which is the primary ossification center where most bone formation occurs.

Ectomorphic

A body type characterized by a slender and tall build.

Endomorphic

A body type characterized by a rounder and broader build, with broader hips.

Female Athlete Triad

A health risk for female athletes comprising the interrelationships between low energy availability, menstrual dysfunction (e.g., amenorrhea), and low bone mineral density (e.g., osteoporosis).

Growth

An increase in body size or the size of a particular body part.

Growth Cartilage

Specialized cartilage located at three sites in a child (epiphyseal plate, joint surface, apophyseal insertions) that is responsible for longitudinal bone growth; vulnerable to trauma.

Maturation

The process of becoming mature and fully functional.

Menarche

The onset of menstruation in girls, serving as a marker of sexual maturation.

Mesomorphic

A body type characterized by a muscular build with broader shoulders.

Older (or Senior)

Arbitrarily defined to include men and women over 65 years of age.

Osteopenia

A condition defined by a bone mineral density between -1 and -2.5 standard deviations below the young adult mean, indicating reduced bone density.

Osteoporosis

A severe condition defined by a bone mineral density below -2.5 standard deviations below the young adult mean, characterized by low bone mass and increased susceptibility to fractures.

Peak Height Velocity (PHV)

The age at which the maximum rate of growth occurs during the pubertal growth spurt.

Preactivation

Muscle activity that occurs before contact with the ground, helping to increase limb stiffness and prepare for impact.

Puberty

A period of time during which secondary sex characteristics develop, and a child transitions to young adulthood, involving significant hormonal and body composition changes.

Resistance Exercise

A specialized method of conditioning involving working against various resistive loads to enhance health, fitness, and performance.

Sarcopenia

The age-related loss of muscle mass and strength, a significant contributor to functional decline in older adults.

Senior

See "Older."

Training Age

The length of time an individual has consistently followed a formalized and supervised resistance training program.

Youth (or Young Athlete)

A term referring to both children and adolescents.