In a head race, finding your base rhythm is everything. The start and sprint sequence take up a small fraction of the race, leaving 4500+ meters to find a good rhythm that will carry you through the race. How to establish this rhythm is difficult to learn and even more difficult to teach, but as coaches I think we err when putting too much emphasis on ratio or on a particular stroke rate.
Nobody races at 2:1 ratio- twice as much time on the recovery as on the drive - but often this ratio is emphasized in practice. So too are certain stroke rates - set pieces at 24/26/28 or some other artificial number. No other sport I know puts such emphasis on rates - not running, cycling or swimming, all of which are rhythmic, repetitive sports like rowing.
I've swum competitively for years and while I am aware of my stroke count per lap, the practice is not centered around that number. If we're doing sprint pieces, my stroke count goes up; when we do longer distance sets, I stretch out and my stroke count comes down. In other words, the speed I'm looking to achieve determines my stroke count, not the other way around.
While a speed coach can be helpful in many ways, it's also beneficial to row some without it or start a piece and don't look at it until you feel that the boat is moving well. Then take a peek and see what rate you're at. But just because a 28 feels good one day or maybe many days, it doesn't mean it's going to be the best rate on race day. Rowing is an outdoor sport, and wind, waves and chop all contribute to changing conditions, so we need to feel what is right, not expect a certain number to be the magic one.
We're looking for a rhythm that is not artificial or robotic, not a certain ratio or a particular number, but something we feel. To try and achieve this, we focus on body mass, or core, and not just on the drive but also on the recovery. While we hang our body weight off the oar on the drive, using legs, quads, glutes and core to push the body to bow, we also want to do active work on the recovery.
Use the core - the abdominals - to roll the body back out of bow. Every action has an equal and opposite reaction so as you move your body to the stern, the boat will continue to accelerate underneath you. Imagine a swing set. If you pump your legs and swing your body, the swing will continue to go higher but if you stop either or even one of these actions, the swing will start to slow down. Accelerate the boat on the drive and ride it on the recovery. Allow the boat to come to you on the recovery - get the body established and get the feet out of the way so the boat can run.
Obviously a still photo can't show you swing so watch some videos of Olympic, World Cup or World Championship races. I've written this article with the single sculler in mind but you can find swing in any good rowing, though establishing it is a little different when you have to work with other people.