Cat Calculator a la Royle

Enter your 20-minute average 500m pace at the top and click the Calculate button at the bottom and your calculated category 500m splits will be displayed. Other fields in the top-half of the calculator can be edited.


This training category calculator is based on some of the training notions of Marlene Royle and others as stated in articles which appear in the Craftsbury Sculling Center's technical tips section. The article that summarizes the categories and their derivation and benefits is called "Performance-Based Training Paces: How Fast or Slow to Row?".

Roughly equivalent zones appear also in Volker Nolte's Rowing Faster in a chapter on Improving Anaerobic Threshold by Wolfgang Fritsch.

The women's racing team at the Ashland Rowing Club uses these training categories to guide their training. It seems to provide a useful framework for structuring workouts and monitoring progress. Your experience may vary.

Several folks I know who subscribe to Royle's training advice have difficulty with the Cat IV "anaerobic threshold" workout of "3 x 20-minutes with 5-7 minutes rest [in] between at stroke rate 24." This is certainly beyond my capability. If my average 500/m pace for 20-minutes all-out is 1:50.0, then my Cat IV 500/m average is 1:52.0. I cannot row 3 x 20 minutes at that pace. Realistically, I might make it through one and a half intervals, but not two and certainly not a third. For what it's worth, I feel very gratified to be able to do 2 x 20 at a pace of 1:55.

On the other hand, the Cat III intervals seem on the easy side. For me, based on the 1:50 split time for 20-minutes, that would be 1:48, which would be quite comfortable in the recommended 5 x 5 minute intervals (same source as above). These are supposed to be "intense" but, in fact, they would be a breeze compared to the suggested 3 x 20-minute intervals.

This is my experience. What's yours?