Final answer:
Lifestyle activity is defined as light or moderate activities integrated into one's daily routine, like walking or household chores, which align with the guideline of being able to talk but not sing during the activity. So the correct option is b.
Step-by-step explanation:
The best definition of lifestyle activity is b. Light or moderate activities you do as part of your daily life. Lifestyle activities include routine movements such as walking to the store, taking the stairs instead of the elevator, gardening, or even household chores. These activities contribute to your overall physical activity level and are crucial because they can be easily incorporated into your daily routine, potentially lowering the risk of various health issues.
According to the 2018 Physical Activity Guidelines, moderate physical activities are defined as those that allow you to talk, but not sing during the activity. These are the types of activities that are typically considered lifestyle activities, as they can be performed without needing to set aside specific time for exercise, which is why so many Americans can engage in them despite not meeting the recommended guidelines for moderate exercise.
Increasing daily lifestyle activities positively impacts health, alongside other lifestyle aspects like diet. By modifying these areas, individuals can not only meet the recommended physical activity guidelines but also potentially slow the rate of aging and improve overall health and weight management.