As Coach Sara pointed out to the group at our August 15 practice, the drive phase of the stroke must be initiated and accelerated with the hips.
Below is a PDF of the article I mentioned at the beginning and end of that practice. It’s almost 25 years old, but the basic physics of rowing are timeless. When you do this correctly, you’re better able to maintain the shapes of power described in the article.
Low stroke ratings (below 18 spm) are optimal opportunities to test and adjust these personal movement strategies. The objective is to maximize power output and stroke efficiency without upsetting the run of the boat.
~Coach Jeremiah Dees