You don't have to control your hartbeat, you have to overreact to control questions (performing heavy mental calculations combined with holding your breath 2 seconds will do the trick!), so your (normal) response to the important questions will be less severe in comparison.
If your response to control question is stronger than your response to relevant questions, you pass the test. It that simple.
It's really not as simple as these anti-polygraph sites would have you
believe.
There's a sensor that's strapped around your chest. If your breathing is
irregular, they'll detect it. Also, doing anything mentally draining
while someone is asking you a question and answering it correctly is not
easy. At some point, you're going to have to focus on the
question. You'd have to be able to consistently deceive them for every
question and keep at it for several hours.
They don't necessarily tell you which questions are the control and
they'll slip in questions that you'll have to think about and answer
honestly. They'll catch your baseline with those. At times, they'll intentionally try
to agitate you by accusing you of lying. It's difficult to
keep cool and it will throw you off balance. You'll forget that you were
trying to trick them.
The government knows about all of these stupid little tricks. People
used to put pins in their shoe or contract their anal sphincter muscle
to generate a response. Examiners now have sensors under your feet and
ass. These tests aren't designed to simply detect that you're
lying. They want to push your buttons and make you crack.
A polygraph is not the same as law enforcement questioning you. You're taking it because you want a security clearance or you want to keep your parole.
You can be stubborn about it and lie and insist that they've got it wrong, but your reading will show that you're holding back on them. If they sense that you're trying to deceive them, they'll fail you.
Over a 22-year period, Robert Hanssen, one of the most notorious spies in US history, passed several polygraph tests during his tenure at the FBI while he also sold secrets to Russia.
Both hanssen and Ames came up inconclusive in their polys. But they were able to cleverly explain them away. Coming up inconclusive is easy, passing outright is hard. To get a job at an intel shop you must pass. The problem with Ames and hanssen was in the organization, not the poly.
You don't have to control your hartbeat, you have to overreact to control questions (performing heavy mental calculations combined with holding your breath 2 seconds will do the trick!), so your (normal) response to the important questions will be less severe in comparison.
If your response to control question is stronger than your response to relevant questions, you pass the test. It that simple.