But did you know that the FitnessGram ™ pacer show is a step-by-step aerobic exercise that gets even more intense? The 20 meter heart rate test begins in 30 seconds. When you start on the line, your speed will increase, but when you hear this signal it will speed up every minute. [Beep] When you hear this sound, one cheek should fill. [ding] Don't forget to run on a straight line and run faster than you can. If the second is not completed before the sound, the attempt is terminated.