Inspired by my experiences in crew rowing, I wrote a proposal that was awarded the UMCG MSc-PhD grant to fund my PhD research on interpersonal coordination dynamics in crew rowing. I explored antiphase rowing, which is theoretically faster but had never been empirically tested on water. To be able to test crew coordination on the water, I developed and programmed the Remo measurement system. The finding that people are surprisingly well-able to row in a novel pattern, even trying for the very first time, furthered my curiosity to better understand how people can join their forces and learn from each other through joint action. Moreover, the reduction of boat velocity fluctuations when people alternate their strokes beautifully illustrates our potency to achieve more when complementing each other’s contributions.
Overview of the dissertation
Crew rowing is often used as the archetypical example of team work, synchronisation processes and joint action. Indeed, it is amazing to see how people are able to row in a crew with up to seven others, applying all their power at maximum stroke rate, yet moving in unison, coordination their movements with perfect precision. Also as a spectator, you see one crew, one boat, rather than individual athletes. But how are these individual athletes able to coordinate their movements with one another? In the current dissertation, we studied crew coordination from a coordination dynamics perspective, considering the rowers as a system of limit cycle oscillators that are coupled (e.g., through the boat that they share).
As illustrated in Chapter 2, the coordination dynamics perspective provides a well-suited approach to study interpersonal coordination: the behaviour of the system as-a-whole emerges from the interaction between the (oscillating) elements that constitute the system (in this case, rowers and boat). Although traditionally rowers strive to row in perfect in-phase coordination, over the course of a century it has been suggested (and incidentally tried out) that rowing in an alternating pattern may be beneficial for performance, which makes a coordination dynamics perspective particularly suitable to study crew rowing. In return, crew rowing provides an excellent experimental paradigm that allows for manipulation of different aspects of the system at the common level (e.g., in- or antiphase pattern), the level of components (e.g., drive-recovery ratio) and the interaction (e.g., the mechanical coupling through the boat). Moreover, crew rowing is a real-life task in which it is functional and thus meaningful (rather than just instructed) to synchronise. While the laboratory ergometer setup allows for more controlled experimentation, the obtained results can be verified in experiments in the real environment: on the water.
We started our experimentation on the water, addressing the general hypothesis held both in science and in practice, namely that if rowers perfectly synchronize their movements in in-phase crew coordination, detrimental boat movements can be minimised, which would result in an optimised conversion of the power that rowers produce into boat speed (Chapter 3). As movement frequency (or stroke rate) was expected to affect both the stability of coordination and movements of the boat, the relation between crew coordination variability and movements of the boat was tested at different stroke rates, varying from 18-34 spm (strokes per minute). The results indicated that variability of crew coordination is indeed related to surge velocity fluctuations of the boat for coordination around the catch, but counter to the direction that was expected. That is, less variable crew coordination actually involved more surge velocity fluctuations. In line with expectations, less variable crew coordination was related to less roll, which is indicative of better lateral balance of the boat. The results showed that more stable crew coordination indeed is related to improved lateral balance but also suggested that deviating from perfect in-phase synchronisation may contribute to minimising velocity fluctuations of the boat and hence, less hydrodynamic drag.
In the subsequent studies (Chapters 4-7), we therefore also tested antiphase crew coordination, which is less conventional for rowing but a well-studied pattern in coordination dynamics. As most coordination dynamics studies generally show that the stability of coordination decreases with an increase in movement frequency (e.g., Kelso, 1984; Schmidt, Carello, & Turvey, 1990), which in the case of antiphase coordination may yield transitions to in-phase coordination, we tested whether rowers would be able to row in in- and antiphase crew coordination at increasing stroke rates, starting at 30 spm and increasing movement frequency until they could not increase stroke rate any further (Chapter 4). We did so in the lab, using an experimental setup of coupled ergometers to reflect the movements of the boat with respect to the water and to mimic the physical connection between rowers via the boat that they share. The results showed rowers were well able to row in antiphase coordination, even at high stroke rates and the less displacement of the ergometer system suggested that the antiphase coordination pattern indeed reduces velocity fluctuations of the boat, compared to in-phase crew coordination.
As clearly shown in the supplementary material video’s in Chapter 5, the ergometer system moves back and forth while rowing in in-phase coordination and remains at more or less the same position in space when rowing in antiphase coordination. The observation that if antiphase coordination breaks down, the ergometer-system starts oscillating at larger amplitudes (see ‘Coordinative breakdown.mp4’) led to the question whether the mechanical coupling through the boat (or ergometer system) that the rowers share may perhaps explain the occurrence of coordinative breakdowns as observed in Chapter 4. Therefore, in Chapter 5 crews rowing in in- and antiphase at 20 and 30 spm were tested on ergometers with and without mechanical coupling. Although the results show no significant difference between with- and without the mechanical coupling conditions in the occurrence of coordinative breakdowns, the stabilising effect of mechanical coupling was clearly reflected in the lower variability of both in- and antiphase crew coordination in the mechanical- compared to the no mechanical coupling condition.
Given the promising results obtained in the lab that showed that rowers are able to row in antiphase, even at high stroke rates as in racing, and given that rowing in antiphase involves less movements of the ergometer system, we set out to test the antiphase rowing on the water. After a promising first case study in Chapter 6 in which the crew was able to perform four 1000 mtrials in in- and antiphase at 20 and 30 spm without breakdowns in coordination, the experiment was repeated with more pairs in Chapter 7. Again, even though it was the very first time these rowers performed the antiphase pattern, they were well able to row in antiphase: all pairs were able to row at least one antiphase trial without breaking down coordination. Rowing in antiphase crew coordination indeed reduced velocity fluctuations of the boat, but did not results in faster racing times in comparison to rowing in in-phase crew coordination.
Together, this dissertation provides a first step in taking crew rowing from a mere metaphorical example to a model task to study interpersonal coordination dynamics processes, and its suitability for testing coupled oscillator predictions though experimentation, both in the lab and on-water. The current dissertation offers incentives for further research in interpersonal coordination, more specifically on the role of attention and perturbations, manipulations of interaction sources (mechanical coupling in particular) and preferred movement frequencies. In return, the obtained results provide insights for the traditional in-phase as the more experimental antiphase crew rowing, showing the importance of considering the crew as one coordinative system, both in science as in crew rowing practice. Given the promising first indications from this dissertation, it seems worthwhile to study the potential benefits of antiphase rowing further, regardless of whether rowing in antiphase ultimately proves to be faster or not: researching antiphase rowing may also contribute to a better understanding of in-phase rowing, both in science and in practice.
Involved in this project: