I have been wondering what the opinion is on rowing and other high intensity cardio activities are. A normal race for me is about 5 minutes of very hard rowing, as fast as possible for the distance. After this my muscles are all shaky. I have read a lot about long steady state cardio and HIIT training but I'd say this falls somewhere in between. I assume it's better than jogging but it would be interesting to hear what people think of this type of cardio training and competition.
It's not traditional high intensity, but its pretty hard. If its something you really enjoy I definitely wouldn't stop doing it, but I wouldn't count it as a variable since you've been doing it for a while.