I am still not sure I am doing them properly...LOL
But I have found it best to do the 2nd through 5th forms in a four count...
Using the 2nd form...
Count one...lift legs and breathe.
Count two...hold for a second elevated
Count three...put legs and head down and exhale
Count four...relax
Then start over for 21 repetitions...or as many as you are up to...
Previously, I had been holding the form until out of breath...which I now believe is wrong...it should be a fairly smooth exercise, almost aerobic, with only a slight pause...