“crunch” your abs more, engage your transverse abdominals, and keep your back safely supported
which one would you vote for?
By engaging your pelvic floor before and during any abs exercise you perform, you better engage your transverse abdominals
20 Tricks to Get Tight, Toned Abs Faster http://bit.ly/2hicSmi
dave94015 
#7has my vote that I liked the most