Mojtaba Jalalvand; Abbas Bahram; Afkham Daneshfar; Saeed Arsham
Abstract
Aim: This study aimed to determine effect of self-control of task difficulty on accurate and movement pattern golf putting. Methodology: Thirty novice undergraduate students (14 Female and 16 male; average age 21.1 ± 1.64 years) were quasi-randomly assigned to two groups. Before performing each ...
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Aim: This study aimed to determine effect of self-control of task difficulty on accurate and movement pattern golf putting. Methodology: Thirty novice undergraduate students (14 Female and 16 male; average age 21.1 ± 1.64 years) were quasi-randomly assigned to two groups. Before performing each trial during the acquisition phase, the self-control group was told they could choose any of the pre-set distances from the target: (25, 50, 75, 100, 125, 150, 175 and, 200 cm). Each self-control participant’s practice schedule was served as the predetermined practice schedule for each corresponding yoked participant. Participants practiced eight blocks of 10 trials. To analyze the radial error (in acquisition and tests phases) and the movement pattern score (in tests) mixed variance analysis with repeated measures on the last factor was used. The movement pattern score in acquisition phase was analyzed using t test. Results: Based on the results, radial errors across different groups in the acquisition phase did not vary, but the radial error of the self-control group in retention, single task transfer and dual-task transfer tests was lower compared to the yoked group (ps < 0.001). In acquisition and test phases, the golf putting movement pattern was better than that of yoked group (ps < 0.001). Conclusion: The efficacy of self-control of task difficulty is explained with reference to the challenge point framework.
Saeed Arsham; Farzam Farahman; Fazlolah Bagheradeh; Elahe Arab ameri; Anoushirvan Kazemnejad
Volume 1, Issue 2 , October 2009, , Pages 103-126
Abstract
The aim of the present study was to introduce the methods to extract and to interpret cinematic data in order to explain movement pattern changes via joint coupling and freezing/freeing phenomena in a healthy right-dominant college male (age:26, height: 172 cm, weight: 80 kg) who practiced balance maintenance ...
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The aim of the present study was to introduce the methods to extract and to interpret cinematic data in order to explain movement pattern changes via joint coupling and freezing/freeing phenomena in a healthy right-dominant college male (age:26, height: 172 cm, weight: 80 kg) who practiced balance maintenance on a stabilometer. Data were gathered using a three-dimensional registration system which consisted of three cameras and a computer program (Sharif Motion Analyzer-SMA) in MATLAB software and measured the position of 19 passive markers located on subject's limbs and stabilometer. Before each trial, the system was calibrated by a metal frame of known dimensions to transform the two-dimensional camera detector values to real three-dimensional coordinates. Then, the following variables were calculated for the first, fifth and ninth trail from a 3(session) × 3(trail) course of practice: 1) stabilometer variability as a performance index; 2) absolute and relative variability of joint angles to evaluate possible freezing-freeing process; 3) cross-correlations between the angular time series in order to evaluate the presence of joint coupling. Finally, the interpretation method to extract variables was presented and some limits of such studies regarding the variability in degrees of freedom were provided.
