It is called the Sorensen Test or Planking Test and during a recent pre employment Musculoskeletal functional check, I had to hold this position for three minutes. Not sure how I’m going to be using it while driving a boat and I think Mr. Sorensen must have a sadistic bent, but I did successfully complete the test. The other guys in my induction group said they also struggled with it and one had to come back several days later to make a second attempt.