Boat stiffness
Concept:	Vertical displacement of the oarlock on one side relative to the oarlock on the other side when loaded with a weight of 10 kg. The stiffness of the boat is generally subdivided into length, width and torsional stiffness. A simple method is described here that measures a combination of width and torsional stiffness. The definition used gives a good indication of the stiffness of the boat and is especially suitable for measuring stiffness differences between boats.
Sizes:	Measured in millimeters.
Effect:	+ A rigid boat: ●  transfers the movement of the handle to the blade more directly and accurately; ●  convert power into speed more efficiently and ●  gives the rower better feedback to feel what crew and boat doing – A slack boat: ●  is more forgiving of rowing mistakes; ●  transfers the forces of blade and boat less directly to the rower.
Measure:	Place the boat in two slings. Fix the stroke side rigger, for example with a rope to the ground or with the help of a block of wood mounted on a wall (both options are drawn below). Pull the bow side oarlock downwards until the stroke side oarlock no longer comes up. Attach a weight of 10 kg to the bow side rigger. Measure with a tape measure how much this oarlock comes down. The vertical distance difference between a loaded and unloaded bow side oarlock is thus measured.
Adjust:	Not applicable.

Measuring the stiffness of the boat with a fixed oarlock and a weight of 10 kilos

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	Seat height
	Oar balance point