Guidelines for Physical Activity in America

The updated Physical Activity Guidelines for Americans adds new scientific evidence supporting the benefits of physical activity on health in children, adolescents, and adults, according to a summary of the guidelines published as a special communication in JAMA.¹

In a systematic review of the scientific evidence supporting physical activity and health, the 2018 Physical Activity Guidelines Advisory Committee used 38 questions and 104 subquestions to grade the consistency and quality of the research that supported physical activity: Strongly and moderately graded research were included in the guidelines.

The types of physical activities listed in the guidelines included:

• Aerobic activity (endurance, cardio activity): activity involving the rhythmic motion of large muscles for a sustained period. The 3 components of aerobic activity are intensity, frequency, and duration.
  
  • Intensity: the effort a person uses to do an activity
    • Moderate (such as a brisk walk)
    • Vigorous (such as running or jogging)
  • Frequency: how often aerobic activity is conducted
  • Duration: length of time aerobic activity is conducted in any single session
• Muscle-strengthening activity includes resistance training and weight lifting to train muscles to hold against a weight or work against an applied force. The 3 components of muscle-strengthening activity are intensity, frequency, and sets and repetitions.
  
  • Intensity: the amount of weight/force used relative to the amount a person can lift.
  • Frequency: how often muscle-strengthening activity is conducted
  • Sets and repetitions: comparable to “duration” in aerobic activity
• Bone-strengthening activity (weight-bearing, weight-loading) can also be aerobic and muscle-strengthening and requires a force on the bones of the body, allowing bone growth and strength.
• Balance activity
• Multicomponent physical activity

Recommendations and Benefits for Children and Adolescents

For children and adolescents, the health benefits associated with physical activity include improvements in bone health, weight status, cardiorespiratory and muscle fitness, cardiometabolic health, cognition, and reduced risk of depression.

The authors of the guidelines recommend that preschool-aged children (aged 3-5 years) should be physically active throughout the day and that such activity should be encouraged for growth and development.

School-aged children and adolescents should be encouraged to participate in physical activity as well and are recommended to have at least 1 h/d of moderate-to-vigorous physical activity.

From the December 01, 2018 Issue of Clinical Advisor