Systematic review of the health benefits of physical activity and fitness in school-aged children and youth

This systematic review synthesized evidence from numerous studies to understand the relationship between physical activity, physical fitness, and various health outcomes in school-aged children and youth.

The primary **interventions** and **exposures** examined were:

**Physical Activity (PA):** This encompassed the total volume (how much), intensity (how hard), and type (what kind) of movement.

**Physical Fitness:** This referred to an individual's capacity to perform physical activity, often measured through components like cardiorespiratory fitness, muscular strength, and flexibility.

The **comparators** were typically lower levels of physical activity or fitness, or sedentary behavior. The review sought to identify dose-response relationships, meaning whether more activity or higher fitness led to greater health benefits.

The **outcome measures** were limited to seven specific health indicators, chosen for their relevance to public health in this age group:

**High Blood Cholesterol:** Elevated levels of lipids in the blood, particularly low-density lipoprotein (LDL) cholesterol, which is a risk factor for cardiovascular disease.

**High Blood Pressure:** Also known as hypertension, a condition where the force of blood against artery walls is too high, increasing the risk of heart disease and stroke.

**Metabolic Syndrome:** A cluster of conditions that occur together, increasing the risk of heart disease, stroke, and type 2 diabetes. These conditions typically include increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels.

**Obesity:** Excessive body fat accumulation that may impair health, commonly assessed using body mass index (BMI) or body fat percentage.

**Low Bone Density:** A condition where bones are weaker than normal, increasing the risk of fractures. This is a precursor to osteoporosis.

**Depression:**