Jumping for ten minutes ! Blimey, not sure if info below is current, but you deserve a medal
Apparently, it works like this -
Doing more exercise earns you more Points. For example, 20 minutes of aerobics will add an extra 1 Point to your weekly total, whereas 20 minutes of jogging will add an extra 4 Points. You can earn as many activity Points in a week as you wish. However, you are only allowed to spend 12 of the extra Points each week on food. The idea is to earn more than you eat.