If someone wants to engage in vigorous intensity activities instead of moderate ones, the recommendations of the American Heart Association and the American College of Sports Medicine is: (30 seconds)

At least 10 minutes of vigorous physical activity at least 3 days a week
At least 20 minutes of vigorous physical activity at least 3 days a week
At least 20 minutes of vigorous physical activity at least 6 days a week
There is no recommendation regarding vigorous physical activity