Rate Ladders: Finding a Pace You Can Repeat

You already know the pace you want to hold. What you do not know is what it costs you at a different rate, and whether the stroke you can produce at 22 is the stroke you can still produce at 26. A rate ladder is the twenty minutes that answers it — worth running as a measurement, not as a workout.

The context

A rate ladder holds the power constant and raises the stroke rate. That single constraint is what makes it a diagnostic rather than a session: work per stroke has to fall, and the rate at which the same power starts to cost more marks the edge of that pace.

Hold 250 W and climb the rate. The work each stroke has to deliver falls as the rate climbs, so the force-time curve has to change to pay for it: the drive shortens, the peak comes down, or both ([1] Cabrera 2006). Total power stays where you set it, so every stroke is now a smaller parcel of work delivered more often.

That is arithmetic rather than physiology. Cabrera's one-dimensional momentum-balance model formalises it: rowing power is the integral of the force curve over the stroke, multiplied by rate, and the model predicts boat velocity from the force curve without being fitted to velocity at all ([1] Cabrera 2006).

One caveat belongs at the front rather than the back. What the monitor reports about your stroke is inferred rather than measured: it is a model of the boat, not a measurement of your body. Anderson's instrumented work put accelerometers on a RowPerfect ergometer and asked whether real-time feedback could improve stroke consistency; the answer was yes for consistency and no for performance ([7] Anderson 2005). Read what the monitor shows as a consistent relative comparison across a ladder, not as an absolute measure of what your body is doing.

The core idea

What changes elsewhere as rate climbs is where the interesting evidence is, and the evidence says something close to the opposite of the coaching room. The common coaching line is that higher rates waste power. The rowing literature says close to the opposite.

Hofmijster's group measured where a rower's mechanical power goes as rate rises from 20 to 36 spm in nine participants. Two losses are available to get rid of: work not captured at the blades, and work lost to velocity fluctuations inside the stroke cycle.

The result is not that both of them shrink. At higher rates the fraction of power reaching average boat velocity rose — but not because everything improved. Propelling efficiency went up, meaning blade losses fell. Velocity efficiency went down, meaning the power lost to velocity fluctuations rose ([2] Hofmijster 2007). Net efficiency still improved, because the gain at the blades was larger than the loss to velocity fluctuation.

The two mechanisms differ. Blade losses fall because blade kinematics change as rate rises; velocity losses rise because the impulse exchange between rower and boat grows as the stroke compresses. Rate is not a tax on the whole stroke. Within the range they measured it is a redistribution, and the redistribution favours the boat.

The velocity cost of a higher rate is not a laboratory curiosity. When eight elite coxless pair crews rowed a stepwise rate test at 20, 24, 28 and 32 spm, the fluctuations in boat velocity through the stroke cycle were strongly correlated with rate and the penalty grew with it: 2000 m race time would have been 4.59 to 5.05 seconds faster in a boat that did not fluctuate at all ([8] Hill 2009). The same work found that a moderate reduction in rate, paid for with more force per stroke, could buy some of that back. Rate buys cadence and costs boat speed.

If internal losses fall with rate, gross efficiency should rise with it — that is the reasoning behind "find your most economical rate". A direct test of the inference found nothing.

Seventeen well-trained female rowers rowed at 28, 34 and 40 spm at submaximal intensity with flywheel power transfer held constant. Gross efficiency did not differ significantly between the three rates ([3] Hofmijster 2009). The internal power losses implied by the argument were not there to find, and a secondary measure that rose with rate — negative power during the stroke cycle — turned out to be unreliable for estimating them.

This is a clean negative result, in trained rowers, over the competitive range, against a plausible mechanism. If you have been told your efficient rate is a specific number, that number is not resting on this evidence.

The how-to

A ladder is a procedure, and it has a shape. Six rungs is the useful number: 18, 20, 22, 24, 26 and 28 spm. The span is not arbitrary. Concept2's own guidance puts 18-22 spm in the band they recommend for stroke sequence and rhythm work, 24-28 spm in the band they recommend for steady state and longer pieces, and 30-36 spm for short distances and interval work ([10] Concept2 2017). A ladder that stops at 28 finishes inside the band a rower can hold for a long session, which is where the reading is worth having.

Three minutes per rung is the other half of the shape, and it is the stage length the classic rowing ramp used, stepping power up every three minutes ([9] Steinacker 1993). Longer and you are measuring fatigue; shorter and the stroke has not settled into the rate you set before the block ends.

Now the question the ladder answers, because this is the part most people skip: does the same split produce the same feeling at a different rate? Not whether the pace is hard — you know that from the 2k. Whether a given split, held at a different rate, asks the same thing of your lungs and your stroke. That is a repeatability question, and it is why a ladder is worth running twice: a number that comes back the same way is a property of you, and a number that does not is a property of the day.

The procedure itself is short and it is strict.

1. Pick one power and stay there. Every rung holds the same watts. This is not a session where the pace climbs; it is a measurement where the rate climbs and the pace is the control.
2. Climb the rungs in order. Ascending, because a ladder run in descending order measures recovery rather than rate response.
3. Change nothing else between blocks. Not the damper, not the seat height, not the warm-up. The damper is the trap: it changes the relationship between the force you make and the force the flywheel sees, so if it moves mid-ladder the only thing you have measured is the damper. Barrett and Manning's rigging study found that rigging set-up by itself was not a primary determinant of rowing performance but a consequence of the rower being larger and stronger ([4] Barrett 2004). A machine setting is the same kind of thing: it is not what produces the result.
4. Take real recovery between blocks. Enough that your breathing settles before the next rate. This is the part people skip, and it is why their ladder drifts: the third rung is entered with the cost of the first two still on the board.
5. Write the split and your effort down at each rung before you start the next. The reading is the trend across the rungs, not the last block.

How to read the result. Cabrera's model puts rowing power at the integral of the force curve over the stroke multiplied by rate ([1] Cabrera 2006), so at a constant power and a rising rate the force-time integral has to come down. That is the constraint the ladder exists to expose.

A ladder that holds is one where the same power feels like the same effort at every rung and the monitor sits at the split you set. The rate changed and nothing else did.

A ladder that drifts is one where the same power starts costing more as the rate climbs: your breathing has to work harder to keep up with the faster stroke, and past a point the monitor cannot sit at the split at all. Where the effort starts to cost more is the rate at which force per stroke starts collapsing: the pace has become rate-limited rather than strength-limited, and past it you are buying rate with technique rather than earning it.

A third pattern matters as much — the rate where the pace stops improving. Concept2's own advice is direct: raise the stroke rate and if the pace does not improve, your technique is suffering, and the rate should come back down to where the pace improves with the stroke intact ([10] Concept2 2017).

One thing will move across the ladder even when your mechanics do not: your breathing. In rowing, breathing entrains with the stroke — every rower in Steinacker's study raised breathing frequency in concert with stroke frequency as the work climbed ([9] Steinacker 1993). Hold 250 W at 18 spm and at 28 spm and you are not breathing the same way, which is part of why the ladder can feel like a different effort at identical watts.

The trade-offs

A ladder is a laboratory instrument, not a workout, and it is worth being blunt about what that costs.

The time cost is real. Six three-minute blocks with recovery between them is roughly twenty minutes for one reading, and a reading is worth having once in a training block, not weekly in the hope of getting fitter.

It is also the wrong tool for several common jobs. It cannot tell you whether you can hold a hard pace, because it holds a moderate one — holding a pace that is hard for you is a different adaptation, and that is threshold work, and it should be done as threshold work. It is not a race-pacing drill, and it does not answer whether your 2k will improve over a season.

That last question is the one people hope the ladder answers, and it is answered elsewhere. Eighteen experienced rowers trained for twelve weeks either entirely below lactate threshold or on a mix of low and high intensity, and both groups improved their 2000 m time by the same magnitude; what differed was the blood lactate response to a given intensity ([6] Ingham 2008). The rate ladder tells you how your mechanics meet a pace. Whether that pace improves over a season is a training question, answered at a different level.

It is not the same tool as a rate cap, though the two get confused. A rate cap fixes the rate and lets the pace move — what you want when you are building aerobic volume and want to read your effort honestly. A rate ladder moves the rate and holds the pace — what you want when you are asking whether one pace is repeatable across rates. Our guide to rate caps and holding rhythm so pace can drift covers that instrument in full; the short version is that the cap changes what you are allowed to do, and the ladder changes what you are allowed to find out.

And the numbers on the screen are not the numbers you pay. Rowing's mechanical efficiency is about 20 per cent, and roughly three-quarters of the energy for a standard 2000 m comes from aerobiosis ([5] Hagerman 1984). A ladder block is a metabolic bill in its own right, even when the monitor shows a tidy constant.

What to do tomorrow

Run one ladder properly before you run it again. Six rungs from 18 to 28 spm, three minutes each, one power, ascending, damper untouched, real recovery. Write the split and your effort down at every rung as you go.

Read the trend, not the last block. Find the first rung where the same power starts costing more than it did at 18. That is your rate limit for that pace today, and it is a measurement rather than a rule.

Repeat it a fortnight later at the same power. The point is not the first number. The point is whether the number comes back — for how to hold a test still enough for that comparison to mean anything, see our guide to what makes a test repeatable.

If the effort starts climbing at 22 spm, the next piece of work is technique rather than a higher rate.

Then do the threshold work separately. A ladder tells you where your mechanics break. Only a hard piece held for a long time tells you whether you can hold a pace.