Tension Arc Research Articles

Multiplanar lumbar, pelvis and kick leg sequencing during soccer instep kicking from different approach angles

Multiplanar kinematic and kinetic sequencing from different approach angles can highlight how soccer players perform fast and accurate kicks. This study therefore aimed to a) determine multiplanar torso, pelvis and kick leg sequencing during instep kicks and b) highlight the effect of different approach angles on these sequencing patterns. Twenty male soccer players (mass 77.9 ± 6.5 kg, height 1.71 ± 0.09 m, age 23.2 ± 3.7 years) performed kicks from self-selected (∼30−45°), straight (0°) and wide (67.5°) approaches and multiplanar lumbo-pelvic, hip and knee angular velocities, moments and powers were derived from 3D motion analysis. The results suggest tension arc release between the upper and lower body functions as a two-stage mechanism. The first phase of arc release was characterised by increases in concentric hip flexion and transverse lumbo-pelvic velocities towards the ball. The second phase was characterised by increasing concentric lumbo-pelvic flexion and knee extension work to angularly accelerate the kicking knee towards foot-to-ball contact. Further, alterations in kinematic and kinetic sequencing helped maintain performance (ball and foot velocities at ball contact) and accuracy at approach angles other than self-selected. These findings can help coaches and practitioners design effective training practices.

Improving Narrative Consistency in Planning-Based Interactive Storytelling

Interactive Storytelling (IS) systems are an emerging class of interactive entertainment applications with emphasis in narrative aspects. This paper deals with stories that have plots centered on a riddle, and describes a mechanism that can be introduced to planning-based IS in order to make the generated stories follow a specified tension arc. Results from experiments with users suggest that the proposed method is capable to bring improvements to these systems.

Whole-body energy transfer strategies during football instep kicking: implications for training practices

ABSTRACT Knowledge of whole-body energy transfer strategies during football instep kicking can help inform empirically grounded training practices. The aim of this study was thus to investigate energy transfer strategies of 15 semi-professional players performing kicks for speed and accuracy. Three-dimensional kinematics and GRFs (both 1000 Hz) were incorporated into segment power analyses to derive energy transfers between the support leg, torso, pelvis and kick leg throughout the kick. Energy transferred from support leg (r = 0.62, P = 0.013) and torso (r = 0.54, P = 0.016) into the pelvis during tension arc formation and leg cocking was redistributed to the kick leg during the downswing (r = 0.76, P < 0.001) and were associated with faster foot velocities at ball contact. This highlights whole-body function during instep kicking. Of particular importance were: (a) regulating support leg energy absorption, (b) eccentric formation and concentric release of a ‘tension arc’ between the torso and kicking hip, and (c) coordinated proximal to distal sequencing of the kick leg. Resistance exercises that replicate the demands of these interactions may help develop more powerful kicking motions and varying task and/or environmental constraints might facilitate development of adaptable energy transfer strategies.

The trunk is exploited for energy transfers of maximal instep soccer kick: A power flow study

The purpose of this study was to investigate the angular kinetic energy transfers and expenditure among the trunk (bisegmented), the pelvis and the kick limb during maximal soccer instep kicking, and to characterize kicking kinetics and kinematics. Eighteen adult male amateur soccer players (24.0 ± 4.1 years old) were assessed. Three-dimensional kinematics and ground reaction force were measured. A 6-degrees-of-freedom model was assumed, comprising the upper trunk, lower trunk, pelvis, thigh, shank and foot, and the thoraco-lumbar, lumbo-pelvic, hip, knee, and ankle joints. Angular kinematics and joint moments were computed. Power flow analysis was done by calculating the joint powers (to describe joint-to-segments energy transfers) and the proximal and distal segment powers (to describe segment-to-segment transfers). Power, kinematic and kinetic time series were presented to describe the energy flows’ directions. The total mechanical energy expenditure (TMEE) at each joint was also calculated. The TMEEs pointed to substantial energy expenditure at the trunk (27% of the summed work produced by the analyzed joints). In the initial phases of kicking, the trunk generates downward energy flows from the upper to the lower trunk and from the lower trunk to the pelvis, and then to the lower limb, sequentially, which favors angular motions for ball contact. There is a formation and release of a tension arc only at the hip joint, and deceleration of the segments slightly sooner than ball contact, differently from theoretical accounts. There are energy flows, hitherto unknown, among the trunk, pelvis and kick limb, revealing mechanical strategies of kicking.

A joint kinetic analysis of rugby place kicking technique to understand why kickers achieve different performance outcomes

We aimed to identify differences in kicking leg and torso mechanics between groups of rugby place kickers who achieve different performance outcomes, and to understand why these features are associated with varying levels of success. Thirty-three experienced place kickers performed maximum effort place kicks, whilst three-dimensional kinematic (240 Hz) and ground reaction force (960 Hz) data were recorded. Kicking leg and torso mechanics were compared between the more successful (‘long’) kickers and two sub groups of less successful kickers (’short’ and ‘wide-left’) using magnitude-based inferences and statistical parametric mapping. Short kickers achieved substantially slower ball velocities compared with the long kickers (20.8 ± 2.2 m/s vs. 27.6 ± 1.7 m/s, respectively) due to performing substantially less positive hip flexor (normalised mean values = 0.071 vs. 0.092) and knee extensor (0.004 vs. 0.009) joint work throughout the downswing, which may be associated with their more front-on body orientation, and potentially a lack of strength or intent. Wide-left kickers achieved comparable ball velocities (26.9 ± 1.6 m/s) to the long kickers, but they were less accurate due to substantially more longitudinal ball spin and a misdirected linear ball velocity. Wide-left kickers created a tension arc across the torso and therefore greater positive hip flexor joint work (normalised mean = 0.112) throughout the downswing than the long kickers. Whilst this may have assisted kicking foot velocity, it also induced greater longitudinal torso rotation during the downswing, and may have affected the ability of the hip to control the direction of the foot trajectory.

Amygdala and orbitofrontal engagement in breach and resolution of expectancy: A case study.

Constant prediction is a process of future-directed information processing (Rohrmeier & Koelsch, 2012). It is a major factor of the interaction with the complexity of the human environment and contributes to updating of the so-called cognitive world model (Brown & Brune, 2012; Bubic, von Cramon, Jacobsen, Schroger, & Schubotz, 2009; Bubic, von Cramon, & Schubotz, 2010; Friston, 2012). The top-down prediction of what is likely to come next is advantageous, for example, for the preparation of fast adequate responses to incoming stimuli (Friston, 2009). In audition it enables the identification of incomplete, noisy, or ambiguous stimuli, the reduction of the orienting response (Huron, 2001; Summerfield & Egner, 2009), and the preparation of more accurate responses (Schultz, Dayan, & Montague, 1997). Predictions are essential for the organism, often resulting in punishment as a result of failures, and rewards for success. Reward and punishment is reflected in negative and positive affective reactions (Grossberg, 2009; Pearce & Wiggins, 2012).Several music studies have examined emotions associated with expectancy (e.g., Koelsch, Kilches, Steinbeis, & Schelinski, 2008; Salimpoor, Benovoy, Larcher, Dagher, & Zatorre, 2011; Steinbeis, Koelsch, & Sloboda, 2005). One central principle underlying the evocation of emotions with music relies in part on expectancy and prediction (Huron, 2006; Koelsch, 2014; Meyer, 1956). Using EEG, Flores-Gutierrez et al. (2007) found a lateralized frontal alpha suppression during listening to unpredictable music, perhaps originating in limbic/paralimbic structures. Using fMRI, it was found that breaches of expectancy evoke blood-oxygen level dependent (BOLD) changes in the amygdala (Koelsch, Fritz, & Schlaug, 2008) and the orbitofrontal cortex (OFC; Tillmann, Janata, & Bharucha, 2003; Koelsch, Fritz, Schulze, Alsop, & Schlaug, 2005). The emotional reaction to unexpected musical information was found to be reflected in increased electrodermal activity (Koelsch et al., 2008; Steinbeis et al., 2005). These regions play an important role in various emotional processes, including breaches of expectancy (Nobre, Coull, Frith, & Mesulam, 1999). Notably, the OFC is, in addition to numerous other affective functions, associated with the evaluation of the emotional significance of sensory stimuli (Rolls, 2000).In summary, limbic/paralimbic circuits including the OFC and the amygdala appear to be important for emotional reactions to expectancy violations in music. Psychologically, breaches of expectancy in music create not only surprise (Koelsch et al., 2008), but also modulate tension (Lehne, Rohrmeier, & Koelsch, 2014). In tonal music, a structural breach is usually followed by a transitory phase, which leads to the resolution of the breach; this transitory phase represents a delay of the expected resolution and relaxation (Koelsch, 2014). Note that the studies mentioned above only explored the breach of expectancy, and not the effects of the resolution of the resulting tension.Expectancy in music and its resulting tension is a process that occurs over time, and usually involves several discrete events. Koelsch (2014) proposed that the different factors giving rise to tension and resolution contribute to a tension arc, with the different factors underlying tension including the build-up of expectancy, its breach, anticipation of resolution, and resolution (with maximum tension during breaches of expectancies and the subsequent transitory phase).The cognitive processing of unexpected chords (i.e., cognitive aspects of irregularity detection) is neurophysiologically reflected in an early right anterior negativity (ERAN), which is mainly generated in inferior fronto-lateral (neo-)cortex (Lehne et al., 2014; Sammler et al., 2013). Thus, unexpected chords elicit both cognitive and emotional processes. As mentioned above, the emotion reactions to unexpected chords appear to be reflected, for example, in an increased activation of the amygdala (Koelsch et al. …

Creative restorations: Holding a mirror to the self in brief dynamic therapy

The author outlines the conceptual framework that underpins psychoanalytic self-psychology, describing the function of the selfobject in meeting the need of the child and later the adult for mirroring, idealisation and essential alikeness, and thereby sustaining the coherence of the self within a structure that takes the form of a tension arc. Drawing from more recent elaborations of the need for optimal responsiveness by the selfobject in mirroring the expansiveness of the self, the author proceeds to compare this conceptual framework with that of Winnicott and Wright, who posited the role of mirroring in the development and realisation of the self. The contribution of mirroring to the facilitation of creativity as well as the relationship between the arts and the realisation of the self are explored in the particular context of the counselling of students in the field of the performing arts. The implications of these concepts are further explored in relation to short-term counselling and this is illustrated with a case example.

Three-dimensional analysis of a lofted instep kick by male and female footballers

There is a paucity of data describing the lofted instep kick and little information on the kinematic differences between male and female footballers. This study provides a preliminary investigation into the differences in motion patterns between the sexes. A four-camera motion analysis system videoed 13 amateur footballers (7 female and 6 male) attempting a standardised task that represented a lofted instep kick of approximately 35 m. Footballers performed 20 kicks, with the three trials categorised closest to the standardised distance retained for statistical analysis. Three-dimensional motion patterns for kicks of 35 m illustrated that female footballers produced greater fluctuation in movement patterns for pelvic, hip joint and thoracolumbar spine motion in the frontal plane; thorax and hip joint transverse rotation; and ankle dorsiflexion/plantarflexion motion. Peak hip extension (P = 0.018), impact hip abduction (P = 0.032), impact ankle plantar flexion (P = 0.030) and resultant ball velocity (P = 0.004) differed significantly between sexes. Principle component analysis highlighted associations between kinematic variables related to ball velocity and sex including a reduced hip abduction and increased internal rotation approaching impact, and greater peak knee flexion, respectively. In summary, increased variation in direction of segment motion, increased backswing and formation of a tension arc by females compared to males, may be related to anthropometric, strength and muscle activation differences. Specifically, this exploratory study indicates future research would benefit from exploring trunk, pelvis and hip kinematics and kinetics, and whether training the trunk, pelvis and hip musculature assists female footballers.

Effectiveness of Selected Fitness Exercises on Stress of Femoral Neck using Musculoskeletal Dynamics Simulations and Finite Element Model.

The purpose of the study was to establish a dynamics model and a three-dimensional (3D) finite element model to analyze loading characteristics of femoral neck during walking, squat, single-leg standing, and forward and lateral lunges. One male volunteer performed three trials of the five movements. The 3D kinematic data were captured and imported into the LifeMOD to establish a musculoskeletal dynamics model to obtain joint reaction and muscle forces of iliacus, gluteus medius, gluteus maximus, psoas major and adductor magnus. The loading data LfeMOD were imported and transformed into a hip finite-element model. The results of the finite element femur model showed that stress was localized along the compression arc and the tension arc. In addition, the trabecular bone and tension lines of the Ward’s triangle also demonstrated high stress. The compact bone received the greatest peak stress in the forward lunge and the least stress in the squat. However, the spongy bone in the femoral neck region had the greatest stress during the walk and the least stress in the squat. The results from this study indicate that the forward lunge may be an effective method to prevent femoral neck fractures. Walking is another effective and simple method that may improve bone mass of the Ward’s triangle and prevent osteoporosis and femoral neck fracture.

Towards consistency in interactive storytelling

Interactive storytelling (IS) systems are an emerging class of interactive entertainment applications with an emphasis on narrative aspects. One of the approaches used to develop IS applications is based on planning algorithms. This article describes two mechanisms that can be introduced to planning-based IS in order to solve two problems that are inherent in this approach. The first is a technique to control the pace at which a story evolves, so that the story that is generated follows a specific tension arc. The second is a method that makes it possible to avoid dead-ends in a story by intervening to justify previous events. These mechanisms help to produce a more enjoyable user experience, since their use tends to result in stories with higher narrative consistency. Results from experiments with users suggest that the proposed mechanisms improve both of the aspects addressed by this article.

The Emotional Impact of Repeated Cognitive Failure on the Evolving Sense of Self, and Kohut's Tension Arc

Cognitive differences and deficits are a fact of life, but this fact has not been highlighted in contemporary psychoanalytic theory. Using the self psychological concept of Kohut's tension arc as an example, this paper suggests that theoretical modifications are necessary to understand and therapeutically work with patients with learning deficits. Specific practical suggestions are made about how to therapeutically help individuals who struggle with these differences in psychobiological loading. Clearly, the inclusion of biological variables in psychoanalytic theory will lend itself to further study of how nature and nurture interact at various levels of the neuraxis.

The Enigmatic Dimension of Sexual Experience: The “Otherness” of Sexuality and Primal Seduction

Sexual experience has an “otherness” about it that distinguishes it from daily, habitual modes of experiencing and relating. This paper attempts to use Freud's and Laplanche's theories of primal seduction by the mother, who sends an “enigmatic signifier” or message of her sexuality to the child whom she nurtures. A tension arc is created between bodily sensations and the enigmatic other carrying over into adult life and constituting a bedrock for the sense of enigma and unfathomableness and the sense of the profound revelation that sometimes accompanies sexual experience. The author articulates links with transference and countertransference forms and offers new possibilities of understanding some clinical phenomena.

EFFECT OF VARIOUS DRIVING FORCES ON HEAT AND MASS TRANSFER IN ARC WELDING

In this study the heat transfer and fluid flow of the molten pool in stationary gas tungsten arc welding using argon shielding gas were investigated. Transporting phenomena from the welding arc to the base material surface, such as current density, heat flux, arc pressure, and shear stress acting on the weld pool surface, were taken from the simulation results of the corresponding welding arc. Various driving forces for the weld pool convection were considered: self-induced electromagnetic, surface tension, buoyancy, and impinging plasma arc forces. Furthermore, the effect of surface depression due to the arc pressure acting on the molten pool surface was considered. Because the fusion boundary has a curved and unknown shape during welding, a boundary-fitted coordinate system was adopted to precisely describe the boundary for the momentum equation. The numerical model was applied to AISI304 stainless steel and compared with the experimental results.

Self Psychology and Its Relationship to the Practice of Group Psychotherapy

This article discusses self psychology as a theory of personality development and conceptual framework for diagnosing psychopathology. It seeks to show how specific components of this theory, including selfobjects, bipolar self, mirroring, tension arc, and nuclear self, can be compared with the "curative factors" of group psychotherapy, as presented by Yalom (1975). These include altruism, group cohesiveness, universality, interpersonal learning, guidance, and family reenactment. Existing literature is used to explain both theories and develop their synthesis.

A New Method for the Production of Active Nitrogen and its Application to the Study of Collision Effects in the Nitrogen Molecular Spectrum

The source described employs a high tension arc and can operate at comparatively high pressures. The afterglow spectrum is that of the Lewis-Rayleigh glow at low pressures, but is modified at the higher pressures. Reasons are given for interpreting this modification as due to exchanges of vibrational energy occurring in collisions between nitrogen molecules. A modification is made to Mitra's theory of active nitrogen.

A Laboratory Study of Nitrogen Fixation in the High Tension Arc

A Laboratory Study of Nitrogen Fixation in the High Tension Arc