Manipulation of the kinematic chain using visual biofeedback

Feedback has been shown to be an influential component in skill development, yet this has not been assessed in movements involving an explosive proximal to distal sequencing pattern. Novices (n=14) were introduced to a lunge touch task. Visual biofeedback were given on the timing and magnitude of rear leg kinematics. Results showed that those who received feedback adapted their movement patterns by developing extension velocity magnitudes in a summative pattern (pre v post, mean ± SD peak ankle angular velocity: biofeedback; 479 ± 181 v 689 ± 117, control; 466 ± 106 v 477 ± 84 deg·sˉ¹), resulting in greater horizontal impulse (mean ± SD: biofeedback; 1.17 ± 0.60 v 1.7 ± 0.89, control; 1.33 ± 0.33 v 1.49 ± 0.33 N·s·kgˉ¹). The changes were retained after six weeks. These results demonstrate that knowledge of performance based biofeedback interventions alone are effective in developing whole limb contributions in an explosive task

Longitudinal manipulation of the kinematic chain using a reducing biofeedback schedule

Feedback has been shown to be an influential component in skill development, yet this has not been assessed longitudinally in a complex motor skill. Novices (n=32) were introduced to a lunge touch task. Visual biofeedback were given on the timing and magnitude of rear leg kinematics. Results showed that those who received feedback adapted their movement patterns by developing extension velocity magnitudes (40.0%, 24.8% and 28.9% increases for the hip, knee and ankle respectively). The changes were retained across 26 weeks, with a reducing visit schedule of feedback. These results demonstrate that knowledge of performance based biofeedback interventions alone are effective in developing whole limb contributions in an explosive task, and that a reducing visit schedule negates dependence on feedback

Coordination variability associated with attendance to a longitudinal reducing biofeedback schedule

The aim of this paper was to assess skill exploration via coordinated variability (CoordVar) during attendance to a longitudinal, reducing biofeedback (BFb) intervention. Novices (n=15 BFb; n=15 Control) were introduced to a lunge touch task. Visual BFb were given on the timing and magnitude of rear leg kinematics. A modified CI2 method (CI2area) was used to quantify CoordVar for rear leg joint couplings. Coefficient of variability was used to quantify CoM horizontal velocity as performance variability (PerfVar). Linear regression 95% confidence intervals were compared between groups to assess changes over time. The BFb group demonstrated increasing CoordVar as a response to the BFb, with all participants showing no change in PerfVar. This highlights the potential for CoordVar to identify the effectiveness of BFb provision by practitioners

Experimental study of the image of their future profession of students of psychology at initial stages of education

В статье рассматривается экспериментальное исследование образа профессии у студентов-психологов на начальном этапе обучения

Use of the kinematic chain in the fencing attacking lunge

Proximal to distal sequencing has been demonstrated in a variety of movements as an optimal solution to generating maximal propulsion. This study aimed to identify whether the kinematic chain is used in the fencing attacking lunge. Six novice and four expert fencers completed attacking lunge movements. Kinematic data were captured, and joint angular velocities compared. The expert group demonstrated a proximal to distal sequence in the rear leg which was not as evident in the novices, resulting in a significantly greater ankle extension velocity (564 ± 132 °.s-1 expert versus 273 ± 184 °.s-1 novice; p<0.05). This sequential pattern capitalizes on the design of the human musculoskeletal system, allowing for greater forward sword velocity to be achieved. The kinematic chain of the rear leg has an optimal solution adopted by expert fencers in the attacking lunge skill

A comparison of Qatari and Chinese cadet table tennis players: analysis of Asian championship team competition

Video analysis was performed during the Asian Cadet Table Tennis Championships to determine playing style and patterns of top and lower ranked nations. China and Qatar were chosen for analysis based on their performance during the tournament (1st/2nd playoff and 7th/8th playoff respectively). Notational analysis techniques were implemented to analyze 3 matches for each nation. Significant (p<0.05) differences were identified in serve and return placement and shot choice. Chinese players used a higher proportion of long return placement and a higher percentage of topspin shots compared to Qatari players. This preliminary study suggests that at cadet level, Chinese players exhibit a more attacking style of play than Qatari players

Implications for physical preparation of cadet male table tennis players: analysis of the 2013 championship singles final

The purpose of this case-study was to attain and describe data on the physical demands placed on elite Asian cadet male table tennis players in high-level competition. The 2013 Asian cadet singles final was notated live while the match was video recorded for further post-analysis. A typical point consisted of 4-5 shots with the player activated for 3.2 s, working for 3.3 s and resting for 17.8 s on average. The frequency of movement types was reported and typical footwork patterns were described for the most common movement types observed (step, linear jump, lateral jump and pivot). Typical footwork sequences were presented for the first two movements when serving and returning. This information could be used to inform a strength and conditioning programme for a developing cadet player seeking to replicate a playing style of an elite Asian cadet player

Notational analysis of the cadet and junior singles table tennis finals at the 2013 Asian championship

The purpose of this paper was to provide a comparison between the two finals of the elite cadet and junior table tennis players. The 2013 Asian singles cadet and junior final matches were notated live and video recorded for further post-analysis. Junior players demonstrated a more variable serve placement strategy and favored the more aggressive topspin cross table return deep into the oppositions forehand. Work rate time was marginally greater per game in the junior finals (cadet vs. junior; 3.1s ± 1.7 3.3s ± 1.8) however junior players had a greater average rally length (5.3 s ± 2.6 and 4.4 ± 0.9) and greater number of high velocity top spin shots (21.5 ± 5.5 and 14.9 ± 5.6). Physicality and aggressive playing style increases with both age and ability level. These data provide a start to inform coaches of the progression between the top levels at both age groups

On-line case discussion assessment in Ultrasound: The effect on student centred and inter-professional learning

In 2009 an asynchronous on-line case discussion assessment was introduced, to replace an existing traditional case-study assessment, within the Medical Ultrasound Programmes at City University London, to help extend collaborative, interprofessional student-led learning skills. Two clinical modules were used to develop the on-line learning method with associated assessments. Students selected and led a clinical case from their department, uploaded anonymised images and case details with questions, to encourage interaction from other colleagues. Thirty students participated in the on-line case discussions. The assessment was evaluated via informal feedback, end of module feedback and an on-line questionnaire. Some students completed two modules, using the on-line discussion, others were involved in only one module, of which 21 out of 26 students completed end of module feedback for the 1st module and 18 out of 20 students completed feedback from the 2nd module. Twelve students out of 30 completed the on-line questionnaire. Feedback suggested that the on-line case discussions were a good learning tool, providing a wide range of cases for students to participate in or read and learn from each other. All students found the cases interesting, engaging and useful, but time consuming. Despite the small numbers involved, useful feedback was provided to assist further development of the assessment, particularly in relation to the number of cases being assessed and length of availability. On-line case discussions are an innovative, engaging method to encourage self directed, collaborative learning which could be utilised in the health care setting to share interesting cases, promote inter-professional and self-directed learning

Leptin Regulates CD16 Expression on Human Monocytes in a Sex-Specific Manner

Fat mass is linked mechanistically to the cardiovascular system through leptin, a 16 kDa protein produced primarily by adipocytes. In addition to increasing blood pressure via hypothalamic-sympathetic pathways, leptin stimulates monocyte migration, cytokine secretion, and other functions that contribute to atherosclerotic plaque development. These functions are also characteristics of CD16-positive monocytes that have been implicated in the clinical progression of atherosclerosis. This investigation sought to determine if leptin promoted the development of such CD16-positive monocytes. Cells from 45 healthy men and women with age ranging from 20 to 59 years were analyzed. Circulating numbers of CD14++16++ monocytes, which are primary producers of TNFα, were positively related to plasma leptin concentrations (P \u3c 0.0001), with a stronger correlation in men (P \u3c 0.05 for leptin × sex interaction). In vitro, recombinant human leptin induced CD16 expression in a dose-related manner (P = 0.02), with a stronger influence on monocytes from men (P = 0.03 for leptin × sex interaction). There were no sex-related differences in total leptin receptor expression on any monocyte subtypes, relative expression of long versus short isoforms of the receptor, or soluble leptin receptor concentrations in the plasma. The number of circulating CD14+16++ monocytes, which preferentially migrate into nascent plaques, was positively related to systolic blood pressure (R = 0.56, P = 0.0008) and intima-media thickness (R = 0.37, P = 0.03), and negatively related to carotid compliance (R = -0.39, P = 0.02). These observations indicate that leptin promotes the development of CD16-positive monocyte populations in a sex-specific manner and that these subpopulations are associated with diminished vascular function