Especially in the masters category it seems that there is growing interest in mixed crew rowing and racing. In coastal rowing the mixed category was recently recognized in the world championships.
In mixed crews, the rowers often are of significantly different size, shape, and weight, and their strength is also often quite different (generally men are stronger than women).
Here we look into different ways to optimize the speed of a mixed crew boat, e.g. how to decide who strokes and who is bow, and how to choose the right oars. Please note that the below represents the opinion of our own mixed crew, Kristina and Pena, and is based on our own experiences in different kinds of boats (Coastal, Olympic shells, and traditional Finnish wooden boats).
Who takes bow seat?
Often the speed of the boat increases when the stronger and heavier rowers sits at bow. This seems to be the case at least when the boat itself is quite heavy, e.g. in the Coastal double which weighs 60kg.
However, the bow rower needs to have a quick catch, otherwise rowing will feel very heavy (like hitting a wall) for the lighter stroke rower.
Oar length and blades
The bigger and stronger rower needs to have longer oars and preferably bigger blades too. This enables the crew to row with similar handle speeds even though their strength-levels are different. If the stronger and weaker rower would row with identical oars the stronger rower would get the oar from catch to finish faster than the weaker can, and in that case the weaker rower would have difficulty in getting the oar to grip water, but would pull through with less power than what the rower is capable of. For a fast mixed crew double, both rowers need to be able to apply aggressive leg power during the first part of the drive.
Read on for tips on how to measure the leg push of each rower, to determine that all crew members are able to contribute to boat speed in an optimal way.
Using data
The crew can benefit from measuring both the oars and the seats to compare and synchronize technique.
Seat measurements show the speed of the leg push, the rhythm (i.e. the ratio between drive and recovery), and the duration of backstop. Seat measurements can be especially useful in revealing if the rowers row with different style (e.g. if one of them opens their back before the other).
Below as an example (not of a mixed crew but of a C2XM of rowers with quite different strength) where the seat speed measurement shows that the red rower opens his back a tad too early: During first leg push the seat of both rowers start out the same, but early on the red seat speed starts decreasing, and reaches backstop later than the blue rower (Pekka is, however, taller, which accounts for some of the difference in timing). Opening the back too early is a typical mistake, which can easily be spotted through seat measurements.
The oar measurement shows that Pekka, who is taller, has a bigger total oar angle. The oar data shows the oar angular velocity during the drive (positive) and recovery (negative) phase, and can be used also for checking the timing of oar work, such as the catch slip.
Below let's look at data of the Quiske mixed crew, Kristina and Pena, who have been rowing together for many years. The seat data shows that because Kristina is rowing with slightly smaller blades she is able to push with her legs as aggressively as Pena (their seat speeds are similarly high), but since she has slightly shorter legs, she reaches backstop earlier. After the recovery, Pena uses a bit of "trampoline effect", which means that he accelerates the seat more towards the catch and also starts his leg push a bit earlier than Kristina. Although Pena starts his leg push earlier he distributes his power a bit differently with a large proportion of the power being applied later on during the leg push ("hang and bang"-style, read more on this here).
Measuring the angular velocity of the oars and their full angles reveal differences which can be minimized by correcting span and oar rigging. Below simultaneously measured oar data from Kristina and Pena showing quite nice alignment in the oar angular velocity. This result indicates that the oars are correctly rigged for this crew.
The point with synchronizing crew technique is of course to maximize boat speed. Boat speed is a direct result of the force being applied to it, and the shape of the boat acceleration during both the drive as well as the recovery shows how efficiently force is used to propel the boat forwards. Below the acceleration and speed behavior of Kristina's and Pena's double during one average stroke. It is important not to cause negative acceleration on the boat during the recovery phase. Also, it is beneficial to make the area of the positive region of the acceleration graph (drive-phase) as large as possible. We've noticed that measuring boat acceleration AND displaying it in real-time to both rowers while rowing, helps focus on a solid powerful drive and a relaxed unobtrusive recovery. The instant feedback can help the rowers find a state of flow where the crew can keep going well together for long distances of blissfully efficient rowing.
With correct rigging there is no need for the rowers to compromise in their rowing power (with the stronger rowing less powerfully, and the weaker pushing for their life) but both rowers can apply optimum power and contribute to the speed of the boat with nicely aligned leg and oar work. As a summary, here are the most important metrics that can be measured with Quiske, and analyzed in the Quiske cloud portal:
- Timing of the seats and oars
- Style (hang and bang, opening of back, rhythm, etc)
- Full oar angles
- Full trajectory of the oars (the blade flight path)
What are your experiences with mixed crew rowing or rowing with partners or kids of different size or strength levels? We'd love to learn more.
Happy rowing,
Quiske crew
Photo credentials: Header picture taken by Ruud Van Veelen (mixed crew Kristina Björknäs and Mikko Lahti at the first 1st Finnish long distance Coastal Championships on Aug 1st 2020)