Rowing Crew Coordination Dynamics at Increasing Stroke Rates

Collective music listening: Movement energy is enhanced by groove and visual social cues

The regularity of musical beat makes it a powerful stimulus promoting movement synchrony among people. Synchrony can increase interpersonal trust, affiliation, and cooperation. Musical pieces can be classified according to the quality of groove; the higher the groove, the more it induces the desire to move. We investigated questions related to collective music-listening among 33 participants in an experiment conducted in a naturalistic yet acoustically controlled setting of a research concert hall with motion tracking. First, does higher groove music induce (1) movement with more energy and (2) higher interpersonal movement coordination? Second, does visual social information manipulated by having eyes open or eyes closed also affect energy and coordination? Participants listened to pieces from four categories formed by crossing groove (high, low) with tempo (higher, lower). Their upper body movement was recorded via head markers. Self-reported ratings of grooviness, emotional valence, emotional intensity, and familiarity were collected after each song. A biomechanically motivated measure of movement energy increased with high-groove songs and was positively correlated with grooviness ratings, confirming the theoretically implied but less tested motor response to groove. Participants’ ratings of emotional valence and emotional intensity correlated positively with movement energy, suggesting that movement energy relates to emotional engagement with music. Movement energy was higher in eyes-open trials, suggesting that seeing each other enhanced participants’ responses, consistent with social facilitation or contagion. Furthermore, interpersonal coordination was higher both for the high-groove and eyes-open conditions, indicating that the social situation of collective music listening affects how music is experienced.

The Role of Vision in Maintaining Stroke Synchronization in K2 Crew-Boat Kayaking

This study investigated the role of vision in maintaining stroke synchronization in crew-boat sprint kayaking. Sixteen sprint kayakers from a national team were paired into eight two-seater (K2) crews. Each crew paddled at high intensity with the back paddler's eyes open or closed in a randomized order. Using video analysis, stroke synchronization was quantified by the timing offsets between the front and back paddlers at four key positions of the stroke. All crews could paddle continuously without capsize or stopping under both visual conditions. In the absence of vision, neither 200-m performance time (p = 0.23, d = 0.47, small effect size) nor stroke rate (p = 0.41, d = 0.31, small effect size) was severely affected. There were no significant effects of vision on stroke synchronization offsets between the front and back paddlers across all key positions (all p > 0.05). Highly skilled paddlers likely relied on the kinesthetic perception to maintain the boat synchronization when visual information was not available.

Equation for analyzing the peak power in aquatic environment: An alternative for olympic rowing athletes

PURPOSE

To develop an equation to provide the peak power (PP) through a specific stimulus performed in an aquatic environment, as well as to correlate morphological, anthropometric and strength variables with rowing performance.

METHODS

The sample consisted of 16 elite young rowing athletes of both sexes (15.7 ± 1.21 years). The strength of upper limbs and lower limbs was verified. To analyze the PP, a 100-m Sprint test was performed on an indoor rowing type ergometer, and after a 72-hour wash-out, the test was repeated in an aquatic environment on a vessel equipped with a global position system. Body composition was analyzed by examining bone densitometry with an X-ray source and maturation was verified by anthropometry.

RESULTS

The tests for water sprint and indoor rowing showed significant reliability (ICC = 0.695; p = 0.0007). The PP aquatic showed reliability with that acquired in indoor rowing (ICC = 0.897; p<0.0001) and was related to maturation (p<0.05). The morphology, anthropometry and strength of the upper limbs were related to the sprint and peak strength in both tests (p<0.05).

CONCLUSION

The equation for the PP in aquatic environment presented by the present study is highly reliable with an indoor ergometer digital ergometer.

Rowing together: Interpersonal coordination dynamics with and without mechanical coupling

Although most research on interpersonal coordination focuses on perceptual forms of interaction, many interpersonal actions also involve interactions of mechanical nature. We examined the effect of mechanical coupling in a rowing task from a coupled oscillator perspective: 16 pairs of rowers rowed on ergometers that were physically connected through slides (mechanical coupling condition) or on separate ergometers (no mechanical coupling condition). They rowed in two patterns (in- and antiphase) and at two movement frequencies (20 and 30 strokes per minute). Seven out of sixteen pairs showed one or more coordinative breakdowns, which only occurred in the antiphase condition. The occurrence of these breakdowns was not affected by mechanical coupling, nor by movement frequency. For the other nine pairs, variability of steady state coordination was substantially lower in the mechanical coupling condition. Together, these results show that the increase in coupling strength through mechanical coupling stabilizes coordination, even more so for antiphase coordination.

All-sense-all networks are suboptimal for sensorimotor synchronization

In human groups that seek to synchronize to a common steady beat, every member can typically perceive every other member. We question whether this naturally occurring all-sense-all condition is optimal for temporal coordination. We consider alternative configurations represented by directed graphs, in which individuals can only hear or see a subset of others. We identify a trade-off in the topology of such networks: While denser graphs provide stronger coupling, improving synchrony, density increases sensitivity to early taps, which produces rushing. Results from an experimental study with music conservatory students show that networks that combine short path length with low density match all-sense-all networks in synchrony while yielding a steadier beat. These findings suggest that professional teams in arts, sports, industry, and the military may improve temporal coordination by employing technology that strategically configures who can track whom.

Bimanual joint action: correlated timing or "bimanual" movements accomplished by two people

A crew of two rowing together in perfect synchrony is an example of a task that requires each performer to maintain meticulous timing when coordinating their movements with the other. At the individual level, temporal coordination of the limbs has been observed in bimanual pointing movements even when made to targets of different distance. Timing of the arms is not independent; rather there is a natural temporal coupling. The aim of this experiment was to investigate whether the temporal characteristics of pointing movements can be observed under joint conditions. Sixteen pairs of participants made short and long, unimanual and bimanual pointing movements. In the unimanual and bimanual solo conditions, participants made the movements alone. In the joint condition, each participant contributed one arm to the joint "bimanual" movements. Absolute temporal coupling at movement initiation and termination was measured by the differences in reaction time and total response time. Relative temporal coupling at movement initiation and termination was measured by correlating reaction time and total response time of the left and right limbs. Pointing movements had synchronous movement termination in the bimanual solo conditions and asynchronous termination in the unimanual solo and bimanual joint conditions. The initiation and termination of the arms were not correlated in the unimanual solo condition (initiation r = 0.01, termination r = 0.03). Small-to-medium correlations (r = 0.19, r = 0.24) were observed in the bimanual joint condition, and they were larger than the unimanual solo condition (p = 0.022, p = 0.063). As expected, there were large correlations in the bimanual solo conditions (r = 0.91, r = 0.81). Our findings suggest that absolute temporal coupling does not occur between individuals, but there is evidence for relative temporal coupling in the bimanual joint condition.

Individual and dyadic rope turning as a window into social coordination

The spontaneous and intentional movement coordination between peoples is well understood. Less is known about such interactions when the coordination is subordinate to the task and when the task involves, next to vision, mechanically induced haptic and kinesthetic coupling between dyadic partners. We therefore investigated dyadic jump rope turning. Fifteen dyadic pairs conjointly turned a jump rope to which five markers were equidistantly attached, and whose movements were recorded in 3D. In addition, each participant turned one side of the rope while the other side was quasi-fixed in an individual baseline condition. The participants' goal was to turn the rope regularly and smoothly. Individual spontaneous turning frequencies differed substantially across participants. Yet, dyadic pairs spontaneously turned the rope at a common frequency, indicative of frequency entrainment. The dyadic rope rotations were less variable despite weaker between near-hand marker coordination than the individual rope rotations, and the degree of performance improvement was most pronounced for participants who were paired with a partner who performed better in the individual condition. The direction and relative strength of the coupling between partners varied substantially across dyads, but the degree of coupling asymmetry had no substantial effect on the rope tuning quality. The absolute degree in which dyadic partners adjusted to each other, however, scaled moderately with their turning performance. Although the individual performances did not predict the dyadic performances, the difference in individual performance between dyadic partners had some predictive value for the dyadic performance. In combination, these results indicate that the partners were functionally adapting to each other in order to satisfy the task goal and suggest that the relative performance differences rather than the individual performances has predictive value for conjoint action.

Multiscale coordination between athletes: Complexity matching in ergometer rowing

Complex systems applications in human movement sciences have increased our understanding of emergent coordination patterns between athletes. In the current study, we take a novel step and propose that movement coordination between athletes is a multiscale phenomenon. Specifically, we investigated so-called "complexity matching" of performance measured in the context of rowing. Sixteen rowers participated in two sessions on rowing ergometers: One individual session of 550 strokes and one dyadic session of 550 strokes side-by-side with a team member. We used evenly-spaced detrended fluctuation analysis (DFA) to calculate the complexity indices (DFA exponents) of the force-peak interval series for each rower in each session. The DFA exponents between team members were uncorrelated in the individual sessions (r = 0.06), but were strongly and significantly correlated when team members rowed together (r = 0.87). Furthermore, we found that complexity matching could not be attributed to the rowers mimicking or locally adapting to each other. These findings contribute to the current theoretical understanding of coordination dynamics in sports.

Textured insoles affect the plantar pressure distribution while elite rowers perform on an indoor rowing machine

INTRODUCTION

During rowing, foot positioning on the foot stretcher is critical to optimise muscle force transmission and boat propulsion. Following the beneficial effects of textured insoles on gait and balance, this study aims at investigating whether passive stimulation of foot mechanoreceptors induced by these insoles may contribute to improving foot loading pattern and symmetry during indoor rowing.

METHODS

Eleven elite rowers were assessed during controlled training on a standard rowing machine while wearing control, low-density or high-density textured insoles. Plantar pressure and knee and trunk kinematics were measured; performance data were recorded from the machine. Insole effect on kinematic parameters, peak and average values of foot force, contact area and position of centre of pressure was assessed with ANOVA and Bonferroni correction for pair-wise comparisons.

RESULTS

A main effect was observed for force and contact area, with the high-density insoles providing greatest values (P<0.035). No interaction was observed between side and insole (P>0.190), even though symmetry was higher with high-density insoles. Kinematics (P = 0.800) and rowing performance were not affected by insole type; a consistent though not statistically significant increase in mean travelled distance was observed for denser insoles (P>0.21).

CONCLUSION

The high-density textured insoles affected foot loading distribution during indoor rowing. Rowers applied greater foot force and over a greater foot stretcher area with the high-density than the low-density and control insoles. These findings and the methodology applied may be relevant for the understanding and monitoring of rowing performance.

Effects of Intensive Crew Training on Individual and Collective Characteristics of Oar Movement in Rowing as a Coxless Pair

This case study examined how two rowers adapted their rowing patterns following crew training as a newly formed coxless pair. The two participants were expert (double-oar) single scull-boat rowers. Performing as a crew in the coxless-pair’s sweep-boat, where each rower operates a single oar, on-the-water data were collected before and after a 6-week intensive team-training program. Rowing patterns were characterized by the horizontal oar angle, oar angular velocity and linear oar-water velocity profiles during the catch (minimal oar angle) to finish (maximal oar angle) half-cycles of the propulsive water phase. After crew training, rowers demonstrated a tighter synchronization and a closer correspondence in oar angle at the moment of catch, together with a closer matching of the evolution over time of their subsequent oar movements. Most likely due to the inherent asymmetries involved in sweep-boat rowing, the stroke rower also developed a somewhat longer-duration larger-amplitude oar movement than the bow rower. Remarkably, both rowers revealed changes in the inter-cycle variability of their individual patterns of rowing. While the initially more variable stroke rower improved the consistency of his rowing pattern over practice, the initially highly consistent bow rower on the contrary relaxed his tendency to always perform in the same way. We discuss how the crew performance changed over training and to what extent it was associated with changes in individual behaviors. Along the way we demonstrate that the often-used measure of average continuous relative phase does not adequately capture the particularities of the coordination pattern observed. Overall, the results obtained at the individual level of analysis suggest that team benefits were obtained through distinct adaptations of the rowers’ individual rowing patterns.

Understanding and Modeling Teams As Dynamical Systems

By its very nature, much of teamwork is distributed across, and not stored within, interdependent people working toward a common goal. In this light, we advocate a systems perspective on teamwork that is based on general coordination principles that are not limited to cognitive, motor, and physiological levels of explanation within the individual. In this article, we present a framework for understanding and modeling teams as dynamical systems and review our empirical findings on teams as dynamical systems. We proceed by (a) considering the question of why study teams as dynamical systems, (b) considering the meaning of dynamical systems concepts (attractors; perturbation; synchronization; fractals) in the context of teams, (c) describe empirical studies of team coordination dynamics at the perceptual-motor, cognitive-behavioral, and cognitive-neurophysiological levels of analysis, and (d) consider the theoretical and practical implications of this approach, including new kinds of explanations of human performance and real-time analysis and performance modeling. Throughout our discussion of the topics we consider how to describe teamwork using equations and/or modeling techniques that describe the dynamics. Finally, we consider what dynamical equations and models do and do not tell us about human performance in teams and suggest future research directions in this area.

The Effect of Different Phases of Synchrony on Pain Threshold in a Drumming Task

Behavioral synchrony has been linked to endorphin activity (Cohen et al., 2010; Sullivan and Rickers, 2013; Sullivan et al., 2014; Tarr et al., 2015, 2016; Weinstein et al., 2016). This has been called the synchrony effect. Synchrony has two dominant phases of movement; in-phase and anti-phase. The majority of research investigating synchrony’s effect on endorphin activity has focused on in-phase synchrony following vigorous activities. The only research to investigate the effects of anti-phase synchrony on endorphin activity found that anti-phase synchronized rowing did not produce the synchrony effect (Sullivan et al., 2014). Anti-phase synchrony, however, is counter-intuitive to the sport of rowing and may have interfered with the synchrony effect. This study investigated the effect of anti-phase synchrony on endorphin activity in a different task (i.e., drumming). University students (n = 30) were asked to drum solo and in in-phase and anti-phase pairs for 3 min. Pain threshold was assessed as an indirect indicator of endorphin activity prior to and following the task. Although the in-phase synchrony effect was not found, a repeated measures ANOVA found that there was a significant difference in pain threshold change among the three conditions [F(2,24) = 4.10, = 0.255, p < 0.05). Post hoc t-tests showed that the anti-phase condition had a significantly greater pain threshold change than both the solo and in-phase conditions at p < 0.05. This is the first time that anti-phase synchrony has been shown to produce the synchrony effect. Because anti-phase drumming may have required more attention between partners than in-phase synchrony, it may have affected self-other merging (Tarr et al., 2014). These results support Tarr et al.’s (2014) model that multiple mechanisms account for the effect of synchrony on pain threshold, and suggest that different characteristics of the activity may influence the synchrony effect.

Interpersonal Coordination and Individual Organization Combined with Shared Phenomenological Experience in Rowing Performance: Two Case Studies

The principal aim of this study was to examine the impact of variability in interpersonal coordination and individual organization on rowing performance. The second aim was to analyze crew phenomenology in order to understand how rowers experience their joint actions when coping with constraints emerging from the race. We conducted a descriptive and exploratory study of two coxless pair crews during a 3000-m rowing race against the clock. As the investigation was performed in an ecological context, we postulated that our understanding of the behavioral dynamics of interpersonal coordination and individual organization and the variability in performance would be enriched through the analysis of crew phenomenology. The behavioral dynamics of individual organization were assessed at kinematic and kinetic levels, and interpersonal coordination was examined by computing the relative phase between oar angles and oar forces and the difference in the oar force impulse of the two rowers. The inter-cycle variability of the behavioral dynamics of one international and one national crew was evaluated by computing the root mean square and the Cauchy index. Inter-cycle variability was considered significantly high when the behavioral and performance data for each cycle were outside of the confidence interval. Crew phenomenology was characterized on the basis of self-confrontation interviews and the rowers' concerns were then analyzed according to course-of-action methodology to identify the shared experiences. Our findings showed that greater behavioral variability could be either “perturbing” or “functional” depending on its impact on performance (boat velocity); the rowers experienced it as sometimes meaningful and sometimes meaningless; and their experiences were similar or diverging. By combining phenomenological and behavioral data, we explain how constraints not manipulated by an experimenter but emerging from the ecological context of a race can be associated with functional adaptations or perturbations of the interpersonal coordination.

There's More to Groove than Bass in Electronic Dance Music: Why Some People Won't Dance to Techno

The purpose of this study was to explore the relationship between audio descriptors for groove-based electronic dance music (EDM) and raters' perceived cognitive, affective, and psychomotor responses. From 198 musical excerpts (length: 15 sec.) representing 11 subgenres of EDM, 19 low-level audio feature descriptors were extracted. A principal component analysis of the feature vectors indicated that the musical excerpts could effectively be classified using five complex measures, describing the rhythmical properties of: (a) the high-frequency band, (b) the mid-frequency band, and (c) the low-frequency band, as well as overall fluctuations in (d) dynamics, and (e) timbres. Using these five complex audio measures, four meaningful clusters of the EDM excerpts emerged with distinct musical attributes comprising music with: (a) isochronous bass and static timbres, (b) isochronous bass with fluctuating dynamics and rhythmical variations in the mid-frequency range, (c) non-isochronous bass and fluctuating timbres, and (d) non-isochronous bass with rhythmical variations in the high frequencies. Raters (N = 99) were each asked to respond to four musical excerpts using a four point Likert-Type scale consisting of items representing cognitive (n = 9), affective (n = 9), and psychomotor (n = 3) domains. Musical excerpts falling under the cluster of "non-isochronous bass with rhythmical variations in the high frequencies" demonstrated the overall highest composite scores as evaluated by the raters. Musical samples falling under the cluster of "isochronous bass with static timbres" demonstrated the overall lowest composite scores as evaluated by the raters. Moreover, music preference was shown to significantly affect the systematic patterning of raters' responses for those with a musical preference for "contemporary" music, "sophisticated" music, and "intense" music.