Why are fitness assessments sometimes categorized by age?

Fitness assessments are often categorized by age primarily because fitness can vary significantly due to age-related physiological changes. As individuals grow older, various factors such as muscle mass, bone density, cardiovascular health, and metabolic rate can change, influencing overall physical performance and fitness levels. This is important for accurate assessments, as a one-size-fits-all approach would not accommodate the differing needs and capabilities of various age groups. By recognizing these differences, fitness professionals can tailor assessments and programs to be more effective for individuals at different life stages, ultimately leading to better outcomes in health and fitness initiatives.

The other options do not capture the essential reason for age categorization in fitness assessments. General population averages can provide insight but aren't the primary reason for age categorization; they are a byproduct of that understanding. Legal implications and restricting tests solely to older adults are not relevant to the purpose of assessing fitness differences across age groups.