Youth Sports Health Glossary

Definitions of key terms in youth athlete health, injury prevention, and sports medicine.

ACL (Anterior Cruciate Ligament)

A major knee ligament that prevents the tibia from sliding forward. ACL tears are among the most common serious injuries in youth sports, with female athletes at 4-8x higher risk.

Concussion

A traumatic brain injury caused by a bump, blow, or jolt to the head that changes how the brain normally works. Most resolve in 2-4 weeks with proper management.

RED-S (Relative Energy Deficiency in Sport)

A syndrome caused by insufficient caloric intake relative to energy expenditure, affecting 10+ body systems including bone health, hormonal function, and immune response.

Periodization

The systematic planning of athletic training using cycles (macrocycles, mesocycles, microcycles) to optimize performance and prevent overtraining.

Growth Plate (Physis)

Areas of developing cartilage tissue near the ends of long bones in children and adolescents. Growth plates are weaker than mature bone, making them vulnerable to fractures during sport.

Return-to-Play Protocol

A graduated, step-by-step process for safely returning an athlete to full competition after injury or concussion, typically involving 6 progressive stages.