Children and Adolescents

Objective: Encourage physical activity (PA) in children to promote lifelong healthy habits.
Recommendation: 60 minutes of moderate to vigorous physical activity daily.
This should include a variety of activities such as aerobic exercises, muscle-strengthening activities, and bone-strengthening activities to ensure overall development. Additionally, incorporating play and recreational sports can make physical activity enjoyable and effective in engaging children.
Importance of Tracking: Patterns of physical activity and sedentary behavior in childhood often track into adulthood.

Approximately 20-28% of US youth engage in the recommended 60 minutes of physical activity daily.
- Breakdown of Participation:
boys typically meet the PA guidelines more than girls
- 23% of boys meet the PA guidelines.
- 17% of girls meet the PA guidelines.
Age-related Decline in PA:
  - 42.5% of children aged 6-11 years meet recommendations.
  - 7.5% of adolescents aged 12-15 years meet recommendations.
  - 5.1% of those aged 16-19 years meet recommendations.
- PA levels start to decrease going into adolescent years because of the removal of recess in middle/high school and also puberty factors play a role, especially in girls.
Global Context: About 30% of children worldwide typically meet PA recommendations.
Children with Disabilities: Often show lower levels of engagement in physical activity.

Health Risks Associated with Excessive Screen Time:
  - Increased adiposity, decreased fitness, and higher levels of blood pressure and blood lipids.
  - Youth aged 5-17 years exhibit elevated HbA1c levels due to sedentary behavior.
  - 65.7% of boys and 64.6% of girls aged 2-17 years spend more than 2 hours of screen time on weekdays (excluding schoolwork).
  - Screen time usage increases with age.
Recommendations on Screen Time:
- 2-3 year olds should limit screen time to no more than 1 hour per day.
- Children under 18 months should avoid screen time altogether.
Psychological Implications: Higher sedentary behavior may correlate with increased risk for depression.

Guidelines Applicable to Children and Adolescents: The adult guidelines for aerobic and resistance exercise testing are applicable but require specific consideration for this population.
Indications for Exercise Testing:
- Clinical exercise testing is generally not recommended unless specific health concerns exist.
- this is because CVD is not a common risk in youth
Procedures:
  - Ensure the child is familiar with testing protocols to reduce stress.
  - Testing equipment should include treadmills, cycle ergometers, and combination ergometers.
  - Muscular strength testing can include handgrip dynamometers and repetition maximum testing (typically as a 10 rep max) to determine limits
  - Recognize that physiological responses to exercise in children differ from adults due to factors like body size, muscle mass, and anaerobic capacity.
- Children tend to have higher psychological responses to exercise than adults for HR, relative oxygen uptake (higher oxidative capacity), and respiratory rate
  - Encouragement and motivation are essential for successful testing outcomes.

Assessments used to gauge body composition, cardiorespiratory fitness, muscular fitness, and flexibility include:
  - Body Composition: Measured using body mass index (BMI), skinfold thickness of tricpes and calf area, or bioelectrical impedance analysis.
  - Cardiorespiratory Fitness Tests: 1-mile walk/run and the Progressive Aerobic Cardiovascular Endurance Run (PACER).
  - Muscular Fitness Tests:
    - Abdominal strength measured by curl-up tests.
    - Trunk strength assessed by trunk lift tests.
    - Upper body strength evaluated by modified pull-ups and push-up tests.
  - Flexibility Tests: Back-saver sit-and-reach test and shoulder stretch are used to assess flexibility.
Standards: Different performance standard zones exist (Healthy Fit Zone, Needs Improvement) based on age and sex.

Female Standards: CRF (Cardiorespiratory Fitness) assessments for ages 5-9 focus on ensuring the healthy fit zone for future risk assessment.
Male Standards:
- Evaluation based on performance in 1-mile run, PACER, abdominal curl-ups, trunk lifts, push-ups, modified pull-ups, and flexibility tests.
- Each test correlates to health risk zones—NI (needs improvement), HFZ (healthy fit zone) showing potential health risks based on scores.

Exercise training is linked to improvements in:
  - Cardiometabolic risk factors
  - Weight management
  - Bone density and strength
  - Psychosocial health and well-being
  - Overall physical fitness
  - Cognitive functions
  - Academic performance
Risk Assessment: Most common risks associated with exercise (musculoskeletal injuries and concussions) are outweighed by benefits in fitness and overall health.

Incorporate a variety of enjoyable, age-appropriate physical activities aiming to ease sedentary behavior and foster lifelong fitness habits.
Strategies for young children include encouraging unstructured and structured physical activities, ensuring safety regarding thermoregulation due to immature systems.
For children with existing health concerns, collaboration with knowledgeable adults in relevant areas is essential before commencing programs.
Structured progression in activity intensity should be monitored, with healthy kids starting with moderate activities leading to gradual increases based on fitness levels and needs.

Young athletes may benefit from increased intensity training for performance improvement and injury reduction.
The complexity and intensity of exercises should be carefully matched with the practice levels of basic movement skills among children.
Emphasis on strength and conditioning may enhance overall athletic performance while reducing risk of injuries.