Or as most people will know it by "the plank".
The longest plank I have been able to do is 60 seconds. Tonight I went to a circuit class, we did 7 exercises all up, 30 seconds per exercise then 60 seconds then 90 seconds then back to 30 seconds. I did and held the plank for the full time each time it rolled around within those 7 exercises. I do believe in the 90 second hold position I was grunting, and sweating and possibly making some disturbing faces but I held the sucker and now my arms hurt, my abs feel tight and I am dead asleep on my feet - but I got a smile on my face baby :-)