This image of President-Elect Donald Trump, Speaker of the House Paul Ryan and Vice President-Elect Mike Pence - was taken on Thursday in the US Capitol.
An important nonverbal guideline is to (almost) never put your hands beneath the table or desk at which you're sitting (An exception for this principle would include; if a person is being reprimanded by their supervisor, if the table/desk is too high, or a person may be relatively short - or other such configurations which are physically awkward. Sometimes it's also best to sit/lean back, in which case their hands/arms wouldn't be on the table/desk [if the meeting is be relatively casual and/or if you're the relative alpha personality in the room]).
However if you're any kind of leader, perceive yourself as a leader, or you want to project the alpha qualities of strength, assertiveness and engagement - your arms and hands should always be on top of the table.
Outside the exceptions of those mentioned above, when a person's arms/hands are beneath a table/desk - the most favorable interpretation is that of significant anxiety. The worst possible interpretation (depending on the other nonverbal, verbal and paralanguage signals with which it's clustered) is clandestine behavior and dishonesty.
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