Blade depth

Whether you are sculling or rowing, your blade is your second point of contact with the river (the first of course being the boat). The purpose of this post is to highlight an aspect of blade design which seems to escape many newer rowers and scullers.  If you hold a blade horizontally over the water at about the height of your rigger and then lower it into the water you will notice that it floats.  If you square it, it will float with the top edge of the spoon just above the surface and the loom above the water.  This is not an accident.  Blades are designed to float at the correct rowing depth – the depth at which they are most efficient, supporting the pressure of the stroke in the water while minimising the amount of resistance offered to the forward motion of the boat.

This is important because many rowers develop a habit of burying the spoon and a good part of the loom into the water at every stroke.  This produces a heavy feeling in the drive phase of the stroke which they mistake for the weight of the boat.  Allowing the blade to float at its natural depth during the stroke makes the same stroke much lighter – the difference being the resistance of the ‘bow-wave’ raised by the loom in the water due to the forward movement of the boat.  The difference can be so marked that some rowers feel they are somehow “not working hard enough” when they first make the change to using the blade at the correct depth.  The truth is that they are actually working much more efficiently and more of the effort they are applying is moving the boat because the ‘drag’ exerted by the blade is greatly reduced.

That said, getting a rower to learn how to ‘float’ the blade can be time-consuming if they have developed a habit of ‘pulling deep’.  They have to re-learn taking the catch by letting the blade fall gently onto the water under its own weight and ‘locking’ the blade at the correct depth as they start their drive.  As so often in rowing, this means they have to take a step back to make a bigger step forward.  They need to break the catch into two parts, first feeling the buoyancy of the blade before beginning the drive from the legs.  It only takes a little practice for most rowers to master this technique if they concentrate on it during drills – although it can take longer to break the habit of pulling deep during normal rowing.

One of the benefits for rowers of correcting blade depth is an easier extraction and tap down,  resulting in better balance.  Scullers may not see this benefit if they are pulling deep with both blades and it is very noticeable that many elite scullers bury far more of the blade than good technique would dictate.  It may simply be that the force these scullers are capable applying makes the additional drag less significant, or that a deeper stroke is in less danger of an uncontrolled ‘rip through’ (where the blade loses its hydrodynamic stability in the water) at the pressures they are applying.  Any elite sculling coaches out there care to comment?

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