Predict 2km Performance Using the Submaximal Rowing Test (SmRT)

Archive post from 3/7/22

The final article I wrote for Science of Rowing in 2022 (note: I started Science of Rowing with Blake Gourley and Joe DeLeo in 2020, then left in 2022 to take the full-time job at Craftsbury) was on a 2015 study that compared a submaximal erg test with a fully motivated 2km erg test in trained, competitive, college-age male rowers.

The researchers took a popular submaximal test from cycling, the “Lamberts and Lambert Submaximal Cycling Test (LSCT),” and made an adaptation for erging. They did the tests and found that the results could reasonably predict 2km performance.

You can do the Submaximal Rowing Test (SmRT) yourself with an accurate heart rate max, a Concept2 (static) erg, and about 15 minutes. Let’s break it down.

Heart Rate Max Testing

You must have an actual tested heart rate max on the erg. You can test your heart rate max in 20-30 minutes using a step test protocol, a recent 2k time (or estimation), chest-worn monitor, and a way to record the data.

Do not use 220-minus-age or any other predictive formula. You must use a chest-worn monitor, not a wrist-worn monitor. The act of gripping the erg handle on each stroke creates a pumping effect that interferes with a wrist-worn heart rate reading.

Heart rate max depends on individual factors AND mode of performance. The amount of muscle mass used and the efficiency of your movement affects your heart rate values. A trained rower doing a heart rate max test on an erg is going to have a different heart rate max than if they did the test running on a treadmill, or if a trained runner did the test on an erg.

I coach a masters rower who tested her heart rate 22 beats above the 220-minus-age so-called calculation. She had never really used heart rate training before because the outputs based on 220-minus-age always looked too low to be challenging. No wonder!

Your heart rate max is a pretty stable number if you’re reasonably fit and stay that way, so do this once and you’re set for years. Test again to get an accurate number if you become significantly more or less fit in the future.

If your 2k time is under 7:50, use Rowing Australia’s published 7-stage step test protocol.

If your 2k time is over 7:50, use this 5-stage step test protocol.

Need an estimator to get 2k time from another recent test piece? The Ultimate Erg Calculator saves the day again. Enter the distance and time for your test piece, then go to the “Paul’s Law” box in the bottom right corner and select “2000m” and it will give you an estimated 2k time. Use that number in the step test protocol to determine the paces for each stage.

The first few stages of the step test protocol should feel very easy. The cardiovascular system needs to get good and warm before it can perform at an all-out maximal effort. You cannot just sit down and achieve an accurate heart rate max in 5-10 minutes. Your final stage of the step test should be at a much faster pace than your 2k split, and your heart rate max is the highest heart rate value sustained for more than 5 seconds during that final stage.

The Submaximal Rowing Test (SmRT) Protocol

We can plan and perform the SmRT in approximately 15 minutes once we have the accurate heart rate max. Do your normal general warm-up, and then do the following with no rest between intervals:

• 6 minutes at 70%HRmax

• 6 minutes at 80%HRmax

• 3 minutes at 90%HRmax

• Record average watts from each stage, as long as the rower stayed within approximately one beat of the heart rate target. If the rower isn’t able to stay close to the targets, attempt the test again after resting or on another occasion to get valid results.

The researchers included a two-minute resting period immediately after the 15-minute test to record heart rate recovery, but did not find that these results were significant in the study population, so you can skip this.

Finally, we can estimate 2km performance from the SmRT results. The final stage of average watts at 90%HRmax was the strongest correlation to 2km average watts, with rowers achieving approximately 75% of their average 2km power during the three minutes at 90%HRmax. To estimate 2km pace, take the average watts from the 90%HRmax stage, multiply by 100, and then divide by 75.

For example, for a rower who achieved an average of 262W during the 90%HRmax stage: 262 multiplied by 100 is 26200, then 26200 divided by 75 is 350, and average watts of 350 for 2km is a time of 6:40.

See my handy spreadsheet here for an automatic calculation. Edit the text in the red square with your average watts at 90%HRmax, and the spreadsheet will calculate the 2km pace information.

Note that your own correlation might be different. As usual, the college-aged male study population means we need to replicate with other demographics to see how the results hold up. I did some very informal testing with a few masters rowers and found that the SmRT generally overestimated 2km performance, but consistently so at about 88% of 2km average pace.