You know when you sleep your breathing slows down, similar to some of the resperation CM's? And thus slowing down your heart rate?

Wouldnt slowing down your heartrate (by slowing your breathing) decrease your responses? shouldnt you want to be increasing your responses on the 'control' questions on the polygraph "test"?

So reducing breathing will do what for you in a Polygraph test?

As soon as you recognize that the question your polygrapher is asking is a “control” question, or, alternatively, immediately after answering the question, change your baseline breathing pattern to produce one of the five pneumograph reactions that DoDPI considers to be most significant in chart scoring:29

Note: None of these manipulations call for deep breathing, that is, filling your lungs to full or nearly full capacity. Such deep breathing is likely to be interpreted by your polygrapher as an attempted countermeasure.

The first reaction, blocking, is also the easiest. It is achieved by simply holding one’s breath for four or five seconds (anything much longer may make your polygrapher suspicious) after breathing out, as illustrated in the DoDPI graphic below30:

The second reaction, a respiration rate decrease, may be produced by simply breathing more slowly for 5-15 seconds, ending before the asking of the next question:

The third scorable reaction, a change in inhalation/exhalation ratio, may be effected by exhaling more slowly than inhaling for 5-15 seconds, ending before the asking of the next question:

The fourth reaction, a decrease in amplitude (also known as suppression), may be produced by taking several shallower breaths and then returning to one’s baseline breathing pattern, as illustrated below. This should be done over the course of 5-15 seconds, ending before the asking of the next question:

The fifth reaction is similar to the fourth, except that breathing becomes shallower gradually before returning to one’s baseline breathing pattern. Again, this should be done for 5-15 seconds, ending before the asking of the next question:

Doing mental CM's (doing hard math problems, picturing yourself in a stressful situation) will increase your heart rate and blood pressure?

Biting your tongue, may also increase heart rate?

Which is the "sphincter" muscle that people talk about?

and what does contracting it mean?

What About the Anal Sphincter Contraction?

The first three editions of The Lie Behind the Lie Detector included constriction of the anal sphincter muscle as a physical countermeasure to be applied timely with the asking of the “control” questions.  This is one of the most discussed polygraph countermeasures (Lykken, 1998; Williams 1996; Reid & Inbau, 1977), and readers may well wonder why it has been dropped from this book.   
In recent years, polygraph manufacturers such as Lafayette and Axciton have begun marketing piezoelectric sensor pads that they claim aid in the detection of physical countermeasures. These pads are typically placed on the seat of the polygraph chair, and additional pads may also be placed on the armrests or beneath the subject’s feet. While no polygrapher has ever demonstrated any ability to detect the anal sphincter contraction employed as a countermeasure, even with the aid of such pads, we cannot exclude the possibility that a sphincter contraction might result in a detectable change in weight distribution over the surface of a piezoelectric sensor pad. Given this uncertainty, we believe that mental countermeasures or tongue-biting, which plainly cannot be detected by such means, are preferable.