We are often asked questions relating to the rowing stroke arc and methods coaches use to position their athletes in the boat to achieve an efficient arc or length of stroke.

One point that is often raised is a measurement used to set a ‘back choc’ setting for the crew to adjust to. As most equipment manufacturers refer measurements for rigging to ‘the centre of the pin’ as a datum line, it’s wise to always work to the pin as a reference when keeping records or setting measurements in the boat. Some coaches use the face of the oarlock as a reference so you need to be clear what measurements you are using if you want to be precise or need to take this difference into account if using other coach’s methods.

Using the ‘back choc’ method, a mark is set a distance behind the centre line of the pin in which the rower can reference when setting the foot stretcher position and its normal to use the centre of the rear wheel of the seat as the point to align to. Many coaches use a measurement between 62cm and 66cm depending on the size of the athletes. Basically this is a ‘rule of thumb’ measurement that in most cases positions the athletes so that a finish angle of between 30-34 degrees is achieved. This saves time in actually setting, marking and working to a set angle at the finish. Coaches who have gone to the trouble of setting out a boat so they know what finish and catch angles are achieved with certain rigs and crew size, have normally noted a corresponding distance that the athlete sits behind the pin and is confident of using the ‘back chock’ method.

Marking and setting the crew to an angle marked on the boat in each seat will give the coach the experience of how the build of the athlete will alter the measurement recorded for the  ‘back choc’ method where the trunk/stomach determines this setting and not leg length. As Span and inboard relationship also effect the positioning of the athlete, these measurements must also be taken into account when using the ‘back choc’ method.