Why does the erg cause more aches and pains than rowing boat


A reader asks “how come there are more “aches and pains” on the erg than in a boat?  And how can one correct that?

My knees don’t do well on an erg, my High School kids also have more problems like more ice packs on the erg.

I know Rowperfect are rowers–but just asking as erging goes hand in hand with the sport.”

I know EXACTLY what you mean and I can explain why this happens. It’s because the Concept2 erg is NOT a boat simulator….. it just fails to operate mechanically the same way your body works in the boat. Here’s a detailed explanation and diagram.

It is taken from the ebook “How to Coach Using Rowperfect” which we sell on our shop.

Static erg versus dynamic erg explained.

The diagram shows how your body moves up and down the slide relative to your Common Centre of Gravity (CCG).  The acceleration into the front stops compresses your knees (hence they hurt especially if you over-compress) and then the change of direction puts a load on your body.  The movement back and forth of both your body weight and the deceleration / acceleration from changing direction of movement is up to 6 x greater than in a boat.

With a dynamic erg (the left hand image) the body movement is much less and when you get to the front stops you are only pushing the mass of the erg flywheel, not the erg flywheel PLUS your body weight PLUS reversing the acceleration into the catch as well.

Once you understand this it’s clear why erging causes injuries and also teaches the WRONG movement for water rowing.

Static versus dynamic ergs

Download the book chapter extract from How to Coach Using Rowperfect which explains this principle. Static versus Dynamic erg

On a static erg, the rower is required to put in six times as much energy accelerating / decelerating just their bodyweight, compared to a boat or a dynamic erg where the energy is split between the bodyweight and the boat/erg.

Cas Rekers (designer of the Rowperfect) has performed tests comparing the ‘indicated’ power output with the flywheel fixed and without the flywheel fixed (floating) – the subject gained about 10-20% power output with a floating flywheel, representing the additional power that the athlete that could apply to the flywheel instead of using that energy to accelerate his bodyweight.

More energy is used up by accelerating just the body backwards and forwards than by accelerating the body + (lighter) boat/erg in opposite directions.

This is also one reason why the ‘catch’ on a static erg feels relatively ‘slack’ compared to a boat: the initial pressure on the feet is actually being used to decelerate/accelerate the body so the acceleration of the handle (as sensed by pressure in the hands) can only begin once the body has changed direction. The catch in the handle feels ‘late’ compared to the catch on the stretcher.

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This Post Has 3 Comments

  1. April

    So what can we do to lessen that pain?

    1. Rebecca Caroe

      April – first suggestion is get used to doing ergs… they get more familiar and that lessens the pain. Second suggestion is to row technically well so that you don’t get injured and have muscle pains.

      1. April

        LOL! I guess that’s it then. I’ve been rowing and erging (with good technique) for 3 1/2 years now. I guess ergs are just a necessary evil! LOL!

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