How much countermeasures intensity is enough?

[How much pucker]

As a previous poster mentioned, mental countermeasures can be pretty strong.  When I dwell on a specific incident for more than about 10 seconds, I  noticeably shake  for 2-3 seconds, and typically hold my breath for another 5 seconds.

Is this too much countermeasures?

Should I find something less tramatic to think about?

Without having any feedback equipment, is there some other method to determine how much is enough?

[George W. Maschke]

It would be inadvisable to employ a mental countermeasure to the point that one physically shakes, because such shaking might be observed by the polygrapher and interpreted as an attempted countermeasure.

On the other hand, suppressed breathing for a few seconds is a scorable reaction, and not a problem so long as it occurs during/after the asking of a "control" question.