Final answer:
The number of weekly training sessions required for fitness maintenance depends on the intensity and duration of the exercise. Adults should aim for either five 30-minute sessions or two 1-hour sessions of moderate-intensity activity per week.
Step-by-step explanation:
The number of weekly training sessions required for fitness maintenance depends on the intensity and duration of the exercise. According to the U.S. Department of Health and Human Services (HHS), adults aged 18 to 64 should engage in 2.5 hours of moderate-intensity aerobic activity each week. This can be achieved through five 30-minute sessions or two 1-hour sessions per week. Alternatively, if engaging in vigorous-intensity aerobic activity, 1.25 hours per week is recommended, which can be achieved through two 30-minute sessions or one 1-hour session per week.