Blood Pressure Raised by TV Time

According to the study covered here, children's blood pressure may go up as they watch TV or play video games. Oddly enough, blood pressure increases independent of the body type of the 3 to 8 year-olds studied did not increase with regular sedentary activity or computer usage, but it did increase when the children watched or played on the TV. I wonder if wearing a special device to measure their blood pressure and trying to play a video game may have caused the kids some undue stress, perhaps.