related to aging and disease. In the second section, we provide an overview of past and current research on coordination dynamics that demonstrates the functional role of variability in human locomotion. Next, the major section of this paper addresses the concept of fractals that has provided new insights
Scott W. Ducharme and Richard E.A. van Emmerik
Daniela Corbetta, Rebecca F. Wiener, Sabrina L. Thurman and Emalie McMahon
process of mind formation and have been argued to play an important role in the formation of infants’ behaviors ( Corbetta, 2009 ; Smith & Gasser, 2005 ; Thelen, 2000 ). We discuss the implications of this embodied view for the development of eye-hand coordination in infancy. The Origins of the
Richard E.A. van Emmerik, Stephanie L. Jones, Michael A. Busa and Jennifer L. Baird
Postural instability, falls, and fear of falling that accompany frailty with aging and disease form major impediments to physical activity. In this article we present a theoretical framework that may help researchers and practitioners in the development and delivery of intervention programs aimed at reducing falls and improving postural stability and locomotion in older individuals and in those with disability due to disease. Based on a review of the dynamical and complex systems perspectives of movement coordination and control, we show that 1) central to developing a movement-based intervention program aimed at fall reduction and prevention is the notion that variability can play a functional role and facilitate movement adaptability, 2) intervention programs aimed at fall reduction should focus more on coordination and stability boundary measures instead of traditional gait and posture outcome variables, and 3) noise-based intervention techniques using stochastic resonance may offer external aids to improve dynamic balance control.
Michael L. Naraine, Jessie Schenk and Milena M. Parent
This paper sought to examine the stakeholder network governance structures of two international and two domestic multisports events focusing on (a) exploring the structural connectedness of these networks and (b) illuminating powerful stakeholders vis-à-vis centrality and the ability to control the network’s flow. An exploratory, comparative case study design was built by means of 58 interviews and 550 archival materials. Findings highlight international sports events are sparsely connected networks with power concentrated in the organizing committee, government, and venue stakeholders, who broker coordination with other stakeholders. In contrast, domestic sport event organizing committees appear more decentralized as coordinating actors: Sport organizations, sponsors, and community-based stakeholders emerged as highly connected, powerful stakeholders. Domestic event governance decentralization highlights a potential imbalance in stakeholder interests through network flow control by multiple actors, while the governments’ centrality in international events demonstrates not only mode-dependent salience but also visibility/reputational risks and jurisdictional responsibilities-based salience.
Nicola J. Hodges
When we watch other people perform actions, this involves many interacting processes comprising cognitive, motor, and visual system interactions. These processes change based on the context of our observations, particularly if the actions are novel and our intention is to learn those actions so we can later reproduce them, or respond to them in an effective way. Over the past 20 years or so I have been involved in research directed at understanding how we learn from watching others, what information guides this learning, and how our learning experiences, whether observational or physical, impact our subsequent observations of others, particularly when we are engaged in action prediction. In this review I take a historical look at action observation research, particularly in reference to motor skill learning, and situate my research, and those of collaborators and students, among the common theoretical and methodological frameworks of the time.
Tonya Toole and Judith C. Kretzschmar
The purposes of this review article are to: 1) present empirical studies which have compared the development of motor skills for boys and girls in the early childhood years, 2) present studies which have made gender comparisons for similar and related motor skills for older adults, and 3) make comparisons between the younger and older age group literature in terms of gender and causal factors contributing to gender differences. It was concluded that: 1) young boys and older men are superior to young girls and older women in power-dependent skills. Biological and environmental factors were discussed as they relate to gender differences in one power-dependent skill, throwing, throughout the life-span, and 2) young girls excel at hopping, skipping, hand-eye coordination, limb and body control, and balance tasks compared to young boys. Of these tasks, balance and hand-eye coordination are the only skills which are typically measured for young children and older adults. For balance in older age, the results are equivocal but suggestions were made for understanding why women may have lost their performance advantage in older adulthood. For hand-eye coordination, women are not clearly better than men as they were in youth. Reasons for life-span changes are suggested.
Kathleen Williams, Kathleen M. Haywood and Mary A. Painter
Both environmental and biological factors have been cited to explain large gender differences in throwing. Because differences are observed as early as three years, some researchers have suggested biological differences may be a primary factor (Nelson et al., 1986). To explore the contribution of these factors more carefully, three groups of children, 7-8 years, 9-10 years, and 11-12 years, were videotaped performing ten forceful overarm throws each with their dominant and nondominant hands. Resultant ball velocities were computed across all trials for each hand. Five trials for each arm, for each participant were categorized using Roberton’s (Roberton & Halverson, 1984) movement components for the overarm throw. Overall significant age differences were obtained for ball velocities for both dominant and nondominant arms, but gender differences were demonstrated only for the dominant arm. Ball velocity differences for the nondominant arm were not evident. Minimal differences in form occurred for the nondominant arm. When the nondominant arm exhibited coordination patterns and performances typical of an unpracticed performer, we suggest that nonbiological factors are important in explaining the large gender differences in throwing widely noted in the literature.
Lynda B. Ransdell and Christine L. Wells
Do women out-perform men in endurance sports? Are women as strong, pound for pound, as men? Many questions have been raised about the ability of women and men to perform physical tasks equally well. The issue of sex differences and similarities in performance has considerable significance today as women seek physically demanding careers in police-work, fire-fighting, the military, industry, and athletics. As more women participate in recreational and career opportunities formerly open only to men, knowledge about sex differences in response to physical exertion and training becomes increasingly important. In this paper we describes differences between the sexes in athletic performance.
Most performance differences are due to variations in morphological (structural) or physiological characteristics typical of women and men (Wells, 1991). Nevertheless, variations in these characteristics are often as large or larger within each sex as they are between the sexes. The same is true of physical performance. Thus, when the entire population is considered, there are extensive differences in performance within each sex, and considerable overlap in performance between the sexes.
We will base our examination of performance differences on the most outstanding performances of each sex: those exemplified by World Records in athletic events. We seek to answer such questions as: How large are sex differences in world record performances? Can existing performance differences be explained entirely by biological differences between the sexes? Or, are a large portion of these performance differ-ences attributable to sociocultural factors?
We will analyze sex differences in performance relative to the human energy system. This system allows an extraordinary range of mechanisms for neuromuscular coordination and metabolism. Because of this, the human has a virtually unlimited movement repertoire and is capable of movements requiring large bursts of energy over very brief periods of time, as well as movements requiring low levels of energy production over very long periods of time. We will progress from sports that require very high intensity and explosive quality movements such as jumping and power lifting, through the “energy spectrum” to feats of endurance such as marathon running, ultra-distance triathlon, and open-water distance swimming.
Due to our desire to focus this paper on a reasonable amount of data, our analysis will be limited as follows:
1) for sex differences in high intensity-brief duration, explosive per-formance, we will discuss the high jump, long jump, and various mea-sures of strength (powerlifting),
2) for sex differences in high intensity-short duration performance, we will present data on sprint running (100m, 400m) and swimming (100m),
3) for sex differences in moderate intensity-moderate duration performance, we will discuss middle-distance running (1500m, 5000m, 10,000m), and swimming (1500m), and
4) for differences in low intensity-long duration performance, we will discuss the marathon, the "Ironman Triathlon," and open ocean distance swimming.
Chad Seifried, Brian Soebbing and Kwame J.A. Agyemang
suggests external environmental conditions shape necessity-, asymmetry-, stability-, and legitimacy-based IR, while efficiency-based IR is founded on internal pressures. Reciprocity-based IR seems to exist from a combination of internal and external influences because reciprocation and coordination among
the audience through the show. Typical stories are constructed around a celebrity either overcoming adversity or learning to adopt the preferred, dominant identity. Bonner ( 2013 ) added that also so called “sore thumb” celebrities who lack co-ordination, rhythm, and a degree of glamor often provide