Yesterday, I did my first rowing workout in years.
I did a hiit pyramid and was in and out of the gym in 25 minutes, and definitely got my hear rate up.

With my newly found interest in rowing in mind, what are some good workouts for high intensity, short -to-medium duration timeframe?

(I'm going to use rowing to supplement my running program.)

I haven't had access to a rower in a few years but used to use them a lot. I would do a lot of intervals. I can't remember if they were pre-programmed or if I had to set the intervals each time. I think I would do something like 60 seconds on, 30 seconds rest. I think it would come to about 15-20 minutes total and I would just always try to beat my previous time. I'd usually snap a pic of my time to keep track.

Now I use an assault bike at home and do the same thing usually.

I have a concept2 and I just use the preloaded standard and "custom" workouts that are on the machine.

The damn fish game is a good workout too.

I use peloton rowing workouts with a Concept 2 in my office gym. Their workouts are all interval-based. I like them quite a bit

https://www.youtube.com/c/DarkHorseRowing

This is the way