Could you elaborate a bit more on the details of your breathing exercise?

Do you do:

   5 second inhale, 5 second exhale
   7 second inhale, 7 second exhale
  10 second inhale, 10 second exhale
   5 second inhale, 5 second exhale
   7 second inhale, 7 second exhale
  10 second inhale, 10 second exhale
  etc..

or do you do:

    5 second inhale, 5 second exhale
    repeat 5 second inhale/exhale X times or for Y minutes
    7 second inhale, 7 second exhale
    repeat 7 second inhale/exhale X times or for Y minutes
   10 second inhale, 10 second exhale
   repeat 10 second inhale/exhale X times or for Y minutes