Ever fumble with the resistance settings on the rowers? It seems like a good idea to leave them on "10" all the time, but it isn't. Some of us row more efficiently (therefore faster) at a lower resistance setting. The smaller you are, in general, the lower the setting should be. This is especially true over longer distances. For short distances (500 m) you'll get away with pulling a bigger gear (it's an expression), but most of us will do better covering longer distances at a lower resistance setting.
I'd say Katie has about got that "thigh bump" down!