Fit for Duty. . . Fit for Life! “Fit for Duty. . .Fit for Life!” is a lifestyle-based column provided by USPHS Dietitians/Nutritionists. Physical Activity Guidelines for Americans, Chapter 2 Submitted by Therapist Professional Advisory Committee (PAC) Healthy Lifestyles Subcommittee’s CDR Scott Gaustad, USPHS and CDR Rita Shapiro, USPHS   In April 2009, the Fit for Duty. . .Fit for Life! article introduced Chapter 1 of the ‘new’ 2008 Physical Activity Guidelines for Americans” (see http://dcp.psc.gov/ccbulletin/articles/Fit_For_Duty_04_2009.aspx). Chapter 1 opened the door for future articles which will educate, excite, and empower you to embrace and promote the importance of physical activity as the tempest for good health as well as disease prevention. These guidelines are designed to provide information and guidance on the types and amounts of physical activity that provide substantial life-long health benefits. Chapter 2 is titled Physical Activity Has Many Health Benefits. It broadly addresses the scientific findings that clearly and unequivocally demonstrate the significant and remarkable health benefits of physical activity. Its central theme is that regardless of age, race, sex, ethnicity, disability, or chronic condition regular physical activity improves cardio-respiratory (heart, lung and blood vessels) and muscular fitness, improves bone health, improves cardio-vascular and metabolic health, and promotes a favorable body composition. The benefits of physical activity on cardio-respiratory health are some of the most extensively documented of all the health benefits. Low cardio-respiratory fitness is a risk factor for heart disease and stroke, the two leading causes of death in the United States. Individuals of all ages, ethnicity, and races who perform moderate or vigorous-intensity aerobic physical activity have a significantly lower risk of cardiovascular disease than do inactive people. Significant reductions in risk of cardiovascular disease occur at levels equivalent to 150 minutes (2 hours and 30 minutes) per week of moderate-intensity aerobic activity which is recommended for adults. Even greater benefits are seen with 200 minutes a week. Regular physical activity strongly reduces the risk of developing type 2 diabetes as well as metabolic syndrome. Good evidence exists that 120-150 minutes a week of moderate intensity physical activity reduces the risk of metabolic syndrome and type 2 diabetes. Chapter 2 also reports that strong scientific evidence exists that physical activity helps people maintain a stable weight over time. Although the evidence is unclear on the optimal amount of physical activity required to maintain or reduce weight, research reports that most individuals need more than a 150 minutes of moderate-intensity activity a week to maintain their weight. Individuals who want to lose weight may need to perform more than 300 minutes of moderate-intensity activity a week to meet weight-control goals. Individuals who are at risk for bone and joint related disorders have slowed the rate of degeneration by actively participating in aerobic, muscle-strengthening, and bone-strengthening programs of moderate or vigorous intensity. Bone, joint, and muscle health benefits are seen in individuals who participate in 90 and up to 300 minutes of physical activity per week. Research studies on physical activity to prevent hip fracture indicate that 120 to 300 minutes a week of physical activity of at least moderate intensity is associated with a reduced risk. The 2008 Guidelines defines exercise as a form of physical activity that is planned, structured, repetitive, and performed with the goal of improving health or fitness. Chapter 2 introduces the reader to the three main types of physical activity: aerobic exercise, muscle-strengthening exercise, and bone-strengthening exercise. Aerobic Activity: also called endurance activity, involves that large muscles of the body moving in a rhythmic manner for a sustained period of time. Examples of aerobic activity include walking, running, jumping rope, and swimming. Muscle-Strengthening Activity: also referred to has resistance training, involves exercising the body’s muscles to work or hold against an applied external force or weight. Examples of muscle-strengthening exercises are weight lifting, using elastic bands or body weight for resistance (climbing a tree or doing push-ups). Bone-strengthening Activity: also referred to as weight-bearing or weight-loading activity, involves creating a force on the bones that promotes bone growth and strength. Examples of bone-strengthening activity include jumping rope, brisk walking, running, and weight-lifting exercises. Chapter 2 further describes how these three kinds of physical activity have three common components: Intensity, Frequency, and Duration/ Repetitions. Below is a brief description of each component: Intensity: how hard a person works – moderate intensity is recommended. Frequency: how often. Duration/Repetitions: how long or how many times a person does the activity. Chapter 2 also explains that the safe and beneficial progression of physical activity is recommended through three core elements: Overload, Progression and Specificity. Overload is the body’s response to an increase in physical stress. Progression is the individual’s progress from one level of fitness to another as the body adapts to overload. Specificity is the body’s response to specific types or kinds of physical activity. The Physical Activity Guidelines Advisory Committee has found overwhelming scientific evidence that participating in regular physical activity provides many health benefits for all Americans. Although reducing the risk of these conditions may require years of participation in regular physical activity, other benefits, such as increased cardio-respiratory fitness, increased muscular strength, and decreased depressive symptoms and blood pressure, require only a few weeks or months of participation in physical activity. For additional information on what is known from research studies about the specific health benefits of physical activity and how much physical activity is needed to get the health benefits, please visit the Web site at http://www.health.gov/paguidelines/guidelines/chapter2.aspx. Remember - Get Out and Get Active! Note: The series “Fit For Duty…Fit for Life!”, is a lifestyle-based column that has been provided by the USPHS Dietitian/Nutritionist PAC (D/N-PAC). Look for “Fit for Duty…Fit for Life!” articles throughout 2009 addressing various issues related to weight management including diet and exercise tips. Current Issue Front Page